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As filed with the Securities and Exchange Commission on August 1, 2014

Reg. No. 333-197303

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

AMENDMENT NO. 1

TO

FORM S-4

REGISTRATION STATEMENT
UNDER
THE SECURITIES ACT OF 1933

First Business Financial Services, Inc.

(Exact name of registrant as specified in its charter)

401 Charmany Drive

Madison, Wisconsin 53719

(608) 238-8008

(Address, including zip code, and telephone number, including area code, of registrant’s principal executive offices)

Corey A. Chambas

Chief Executive Officer

First Business Financial Services, Inc.

401 Charmany Drive

Madison, Wisconsin 53719

Telephone No.:  (608) 238-8008

Facsimile No.: (608) 232-5978

(Address, including zip code, and telephone number,

including area code, of agent for service)

Copies to:

Approximate date of commencement of proposed sale to the public:  As soon as practicable after this registration statement becomes effective and upon completion of the merger.

If the securities being registered on this Form are being offered in connection with the formation of a holding company and there is compliance with General Instruction G, please check the following box.  o

If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.  o

If this Form is a post-effective amendment filed pursuant to Rule 462(d) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.  o

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company.  See the definitions of “large accelerated filer,” “accelerated filer” and “smaller reporting company” in Rule 12b-2 of the Exchange Act.  (Check one):

The Registrant hereby amends this Registration Statement on such date or dates as may be necessary to delay its effective date until the Registrant shall file a further amendment which specifically states that this Registration Statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act of 1933 or until this Registration Statement shall become effective on such date as the Commission, acting pursuant to said Section 8(a), may determine.

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SUBJECT TO COMPLETION, DATED August 1, 2014

The information in this prospectus is not complete and may be changed. We may not sell these securities until the registration statement filed with the Securities and Exchange Commission is effective. This prospectus is not an offer to sell these securities and it is not soliciting an offer to buy these securities in any state where the offer or sale is not permitted.

MERGER PROPOSED—YOUR VOTE IS VERY IMPORTANT

First Business Financial Services, Inc., which we refer to as “First Business” or “we”, and Aslin Group, Inc., which we refer to as “Aslin Group,” have entered into an Agreement and Plan of Merger dated as of May 22, 2014 (which we refer to sometimes as the “Merger Agreement”), which provides for the combination of the two companies.  Under the Merger Agreement, a wholly-owned subsidiary of First Business will merge with and into Aslin Group, with Aslin Group remaining as the surviving entity and thereby becoming a wholly-owned subsidiary of First Business (which transaction we refer to as the “merger”).  Immediately after the merger, under the Merger Agreement, Aslin Group will merge with and into First Business, with First Business remaining as the surviving entity (which transaction we refer to as the “second merger”).  The merger and the second merger are together referred to as the “mergers”.  As a result of the mergers, Aslin Group’s wholly-owned subsidiary, Alterra Bank, will become a wholly-owned subsidiary of First Business.

Before we complete the mergers, the stockholders of Aslin Group must approve the Merger Agreement and the transactions contemplated thereby.  A special meeting of Aslin Group stockholders will be held on September 17, 2014 for that purpose.

At the effective time of the merger, each share of Aslin Group common stock issued and outstanding immediately prior to the effective time (other than shares of Aslin Group common stock owned by First Business or its subsidiaries, or shares of Aslin Group common stock held by stockholders that have validly exercised appraisal rights under the under Section 262 et seq. of the Delaware General Corporation Law with respect to such shares) will cease to be outstanding and will be converted into the right to receive per share consideration valued at $14,435.59, which will be payable in (i) an amount of cash equal to $6,496.02 (the “Cash Amount”), and (ii) a number shares of First Business common stock having a value of $7,939.57 (the “Stock Amount”).  The number of shares of First Business common stock that each share of Aslin Group common stock will have the right to receive as the Stock Amount will equal $7,939.57 divided by the Bloomberg VWAP (as defined below) of First Business common stock; provided, however, that if the number of shares as so calculated (1) is greater than 233.5154, such number will be reduced to 233.5154, or (2) is less than 155.6766, such number will be increased to 155.6766.  As a result, if the Bloomberg VWAP of the First Business common stock is less than $34.00, the value of the Stock Amount will be less than $7,939.57, and if the Bloomberg VWAP exceeds $51.00, the value of the Stock Amount will be greater than $7,939.57.  The aggregate merger consideration payable to Aslin Group’s stockholders will be $30,105,423, and the maximum number of shares of First Business common stock that may be issued to Aslin Group’s stockholders in the merger is 486,996, based on 2,085.5 shares of Aslin Group stock anticipated to be outstanding as of the effective time of the merger.  Cash will be paid in lieu of issuing fractional shares of First Business common stock.  “Bloomberg VWAP” is defined as the volume-weighted average closing price of First Business common stock on NASDAQ according to the Bloomberg VWAP Price and Volume Dashboard during the 10 consecutive trading days ending on and including the third trading day immediately before the date the merger closes.

We expect the mergers, taken together, to be a tax-free transaction for Aslin Group stockholders except as provided in “Material United States Federal Income Tax Consequences of the Mergers”.

The market price of First Business common stock will fluctuate before the merger.  You should obtain a current stock price quotation for First Business common stock.  First Business common stock is traded on The NASDAQ Global Select Market under the symbol “FBIZ”.

Aslin Group’s board of directors has unanimously determined that the combination of Aslin Group and First Business is in the best interests of Aslin Group stockholders based upon its analysis, investigation and deliberation, and Aslin Group’s board of directors unanimously recommends that the Aslin Group stockholders vote “FOR” the approval of the Merger Agreement and the transactions contemplated thereby.  Stockholders of Aslin Group are also being asked to vote on a proposal to approve certain payments and benefits to Pamela Berneking, President and Chief Executive Officer of Alterra Bank.  The proposal requires the affirmative vote of more than 75% of the issued and outstanding shares of Aslin Group common stock as of the record date, excluding those shares held by Ms. Berneking.  Approval of these payments is not a condition of the merger.  Aslin Group’s board of directors unanimously recommends (except for Ms. Berneking, who abstained from the recommendation) that the Aslin Group stockholders vote “FOR” the approval of the proposal regarding the payments and benefits to Ms. Berneking.

You should read this entire proxy statement/prospectus, including the appendices and the documents incorporated by reference into the document, carefully because it contains important information about the merger and the related

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transactions.  In particular, you should read carefully the information under the section entitled “Risk Factors” beginning on page 12.

The shares of First Business common stock are not savings accounts, deposits or other obligations of any bank or savings association and are not insured by the Federal Deposit Insurance Corporation or any other governmental agency.  Stock is subject to investment risks, including loss of value.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved the merger described in this proxy statement/prospectus or the First Business common stock to be issued in the merger, or passed upon the adequacy or accuracy of this proxy statement/prospectus.  Any representation to the contrary is a criminal offense.

This proxy statement/prospectus is dated       , 2014.

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This document incorporates by reference important business and financial information about First Business that is not included in or delivered with this document.  See “Incorporation of Certain Documents by Reference” beginning on page 75 of the document for a list of documents that First Business has incorporated by reference into this document.  These documents are available to you without charge upon written or oral request made to:

First Business Financial Services, Inc.
401 Charmany Drive
Madison, Wisconsin 53719
Attention: Corporate Secretary
(608) 238-8008

To obtain timely delivery of these documents, you must request the information no later than September 10, 2014, in order to receive them before Aslin Group’s special meeting of stockholders.

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ASLIN GROUP, INC.
11300 Tomahawk Creek Parkway, Suite 100
Leawood, KS 66211

NOTICE OF SPECIAL MEETING OF STOCKHOLDERS
TO BE HELD ON SEPTEMBER 17, 2014

NOTICE IS HEREBY GIVEN that a special meeting of stockholders of Aslin Group, Inc. which we refer to as “Aslin Group”, will be held at Aslin Group’s principal executive offices located at 11300 Tomahawk Creek Parkway, Suite 100, Leawood, Kansas, at  10:00 am Central Time, on September 17, 2014, for the following purposes:

1.              To approve the Agreement and Plan of Merger, which we refer to as the “Merger Agreement,” dated as of May 22, 2014, between First Business Financial Services, Inc., Aslin Group, and AGI Acquisition Corp., and the transactions contemplated thereby. This proposal is referred to as the “Merger Proposal”.

2.              To approve certain payments and benefits to Pamela Berneking, President and Chief Executive Officer of Alterra Bank.  This proposal is referred to as the “280G Proposal”.  Approval of the 280G Proposal is not a condition of the merger.

Aslin Group will transact no other business at the special meeting, except for business properly brought before the special meeting or any adjournment or postponement of such meeting.

The Merger Proposal and the 280G Proposal are described in more detail in the attached proxy statement/prospectus, which you should read carefully in its entirety before you vote.  A copy of the Merger Agreement is attached as Appendix A to the proxy statement/prospectus.

The record date for the special meeting is      , 2014.  All holders of record of Aslin Group common stock at the close of business on the record date will be notified of the special meeting.  Only holders of record of Aslin Group common stock at the close of business on       , 2014, will be entitled to vote at the special meeting and any adjournments or postponements thereof.  Any stockholder entitled to attend and vote at the special meeting is entitled to appoint a proxy to attend and vote on such stockholder’s behalf.  Such proxy need not be a holder of Aslin Group common stock.

Your vote is very important.  To ensure your representation at the special meeting, please complete and return the enclosed proxy card.  Please vote promptly whether or not you expect to attend the special meeting.  Submitting a proxy now will not prevent you from being able to vote in person at the special meeting.

Aslin Group’s board of directors has unanimously adopted and approved the Merger Agreement and the transactions contemplated thereby, and recommends that you vote “FOR” approval of the Merger Proposal and the 280G Proposal.

BY ORDER OF THE CHAIRMAN OF THE BOARD OF DIRECTORS

Malcolm M. Aslin

Chairman and Chief Executive Officer

, 2014

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QUESTIONS AND ANSWERS ABOUT THE MERGER AND SPECIAL MEETING

The following questions and answers briefly address some commonly asked questions about the merger and the special meeting.  They may not include all the information that is important to the stockholders of Aslin Group.  Each stockholder of Aslin Group should read this entire proxy statement/prospectus carefully, including the appendices and other documents referred to in this proxy statement/prospectus.

Q:                      Why am I receiving these materials?

A:                       Aslin Group is sending these materials to its stockholders to help them decide how to vote their shares of Aslin Group common stock with respect to the proposed merger and the other matters to be considered at the special meeting described below.

The merger cannot be completed unless Aslin Group stockholders approve the Merger Agreement.  Aslin Group is holding a special meeting of stockholders to vote on the Merger Agreement as described in “Special Meeting of Stockholders”.  Information about the special meeting and the merger is contained in this proxy statement/prospectus.

This proxy statement/prospectus constitutes a prospectus of First Business and a proxy statement of Aslin Group.  It is a proxy statement because the board of directors of Aslin Group is soliciting proxies from Aslin Group’s stockholders.  It is a prospectus because First Business will issue shares of its common stock in exchange for shares of Aslin Group common stock in the merger.

Q:                      What will Aslin Group stockholders receive in the merger?

A:                       Under the terms of the Merger Agreement, Aslin Group stockholders will receive their pro rata share of the total consideration, which consists of (i) $13,547,449.71 in cash, and (ii) shares of First Business common stock that, valued at the volume-weighted average closing price of First Business common stock on The NASDAQ Global Select Market, which we refer to as “NASDAQ”, according to the Bloomberg VWAP (as defined below), ranging between $34.00 per share and $51.00 per share, will have a total value of $16,557,973.24.  “Bloomberg VWAP” is defined as the volume-weighted average closing price of First Business common stock on NASDAQ according to the Bloomberg VWAP Price and Volume Dashboard during the 10 consecutive trading days ending on and including the third trading day immediately before the date the merger closes.

Q:                      What will an Aslin Group stockholder receive for each share of Aslin Group common stock?

A:                       At the effective time of the merger, each share of Aslin Group common stock issued and outstanding immediately prior to the effective time (other than shares of Aslin Group common stock owned by First Business or its subsidiaries, or shares of Aslin Group common stock held by stockholders that have validly exercised appraisal rights under Section 262 et seq. of the Delaware General Corporation Law, which we refer to as the “DGCL,” with respect to such shares) will cease to be outstanding and will be converted into the right to receive per share consideration valued at $14,435.59, which will be payable in (i) an amount of cash equal to $6,496.02, and (ii) a number shares of First Business common stock having a value of $7,939.57.  The number of shares of First Business common stock that each share of Aslin Group common stock will have the right to receive as the Stock Amount will equal $7,939.57 divided by the Bloomberg VWAP of the First Business common stock; provided, however, that if the number of shares as so calculated (1) is greater than 233.5154, such number will be reduced to 233.5154, or (2) is less than 155.6766, such number will be increased to 155.6766.  As a result, if the Bloomberg VWAP of the First Business common stock is less than $34.00, the value of the Stock Amount will be less than $7,939.57, and if the Bloomberg VWAP exceeds $51.00, the value of the Stock Amount will be greater than $7,939.57.  Cash will be paid in lieu of issuing fractional shares of First Business common stock.  See “The Merger” beginning on page 24 for a more detailed discussion of the per-share merger consideration.

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Q:                      How are outstanding Aslin Group stock options, restricted stock and warrants addressed in the Merger Agreement?

A:                       On the effective date of the merger, all outstanding unvested stock options, restricted stock and warrants issued by Aslin Group will vest.  Immediately prior to the completion of the merger, all options and warrants will have been exercised, and Aslin Group will have received the entire exercise price for the stock options and warrants. The shares of Aslin Group common stock issued upon the exercise of the warrants and options will be exchanged for shares of First Business common stock pursuant to the Merger Agreement.

Q:                      When do First Business and Aslin Group expect to complete the merger?

A:                       First Business and Aslin Group expect to complete the merger after all conditions to the merger in the Merger Agreement are satisfied or waived, including after stockholder approvals are received at the special meeting of Aslin Group stockholders and all required regulatory approvals are received.  First Business and Aslin Group currently expect to complete the merger in late 2014.  It is possible, however, that as a result of factors outside of either company’s control, the merger may be completed at a later time, or may not be completed at all.

Q:                      How will the merger consideration received by Aslin Group stockholders affect First Business shareholders?

A:                       As a result of First Business’ issuance of new shares to Aslin Group stockholders in combination with the cash being paid by First Business, current First Business shareholders will experience dilution in terms of percentage of ownership.  Following the closing of the merger, current First Business shareholders will own approximately 91% of the outstanding common stock of First Business, and current Aslin Group stockholders will own approximately 9% of the outstanding common stock of First Business.  These percentages are for illustration purposes only and are based upon an assumed Bloomberg VWAP of the First Business common stock of $42.50, and will increase or decrease based on the actual Bloomberg VWAP of the First Business common stock as described in more detail on page 24.

Q:                      What am I being asked to vote on?

A:                       Aslin Group stockholders are being asked to vote on the following proposals:

1.              Approval of the Merger Proposal.

2.              Approval of the 280G Proposal.  Approval of the 280G Proposal is not a condition of the merger.

Q:                      How does the board of directors of Aslin Group recommend that I vote?

A:                       Aslin Group’s board of directors unanimously recommends that Aslin Group stockholders vote “FOR” the proposals described in this proxy statement/prospectus (except for Ms. Berneking who abstained with respect to the recommendation of the 280G Proposal).

For a discussion of interests in Aslin Group’s directors and executive officers in the merger that may be different from, or in addition to, the interests of Aslin Group stockholders generally, see “The Merger—Interests of Aslin Group Directors and Executive Officers in the Merger,” beginning on page 36.

Q:                      What do I need to do now?

A:                       After carefully reading and considering the information contained in this proxy statement/prospectus, Aslin Group stockholders should complete, sign and date the enclosed proxy card and return it in the enclosed envelope as soon as possible so that their shares will be represented at Aslin Group’s special meeting.

Please follow the instructions set forth on the proxy card or on the voting instruction form provided by the record holder if your shares are held in the name of your broker or other nominee.

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Q:                      How do I cast my vote?

A:                       If you are a stockholder of record of Aslin Group as of the record date for the special meeting, you may vote by signing and dating the enclosed proxy card and returning it in the postage-paid envelope provided.  You may also cast your vote in person at Aslin Group’s special meeting.

Q:                      When and where is the special meeting?

A:                       The special meeting of Aslin Group stockholders will be held at Aslin Group’s principal executive offices located at 11300 Tomahawk Creek Parkway, Suite 100, Leawood, Kansas, at 10:00 am Central Time, on September 17, 2014.  All stockholders of Aslin Group as of the record date, or their duly appointed proxies, may attend the special meeting.

Q:                      What vote is required to approve each proposal to be considered at the special meeting?

A:                       Approval of the Merger Proposal requires the affirmative vote of a majority of all of the outstanding shares of Aslin Group, which we refer to as the “Requisite Vote”.  The affirmative vote of more than 75% of the issued and outstanding shares of Aslin Group common stock as of the record date, excluding those shares held by Pamela Berneking, is required to approve the 280G Proposal.  Abstentions are not considered votes cast, but are included in determining whether there is a quorum present.

Q:                      What if I abstain from voting or do not vote?

A:                       For the purposes of the special meeting, an abstention, which occurs when an Aslin Group stockholder attends the special meeting, either in person or by proxy, but abstains from voting, will have the same effect as a vote against the Merger Proposal and the 280G Proposal.

Q:                      May I change my vote or revoke my proxy after I have delivered my proxy or voting instruction card?

A:                       Yes.  You may change your vote at any time before your proxy is voted at the applicable special meeting:

·                  by sending a notice of revocation to the corporate secretary of Aslin Group;

·                  by sending a completed proxy card bearing a later date than your original proxy card; or

·                  by attending the special meeting and voting in person and requesting to change your vote; however, your attendance alone will not revoke any proxy.

If you choose the first method, you must take the described action no later than the beginning of the special meeting.  If you choose to send a completed proxy card bearing a later date than your original proxy card, the new proxy card must be received before the beginning of the special meeting.  If you have instructed a bank, broker or other nominee to vote your shares of Aslin Group common stock, you must follow the directions you receive from your bank, broker or other nominee in order to change or revoke your vote.

Q:                     What happens if I sell my shares after the applicable record date but before the applicable special meeting?

A:                       The applicable record date for the special meeting is earlier than both the date of such meeting and the date that the merger is expected to be completed.  If you transfer your Aslin Group common stock after the record date but before the date of the special meeting, you will retain your right to vote at the special meeting (provided that such shares remain outstanding on the date of the special meeting), but you will not have the right to receive any merger consideration for the transferred shares.  You will only be entitled to receive the merger consideration for shares that you own at the effective time of the merger.

Q:                      What do I do if I receive more than one proxy statement/prospectus or set of voting instructions?

A:                       If you hold shares directly as a record holder and also through a nominee, you may receive more than one proxy statement/prospectus and/or set of voting instructions relating to the applicable special meeting.  Each of these should be voted or returned separately to ensure that all of your shares are voted.

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Q:                      What are the federal income tax consequences of the merger?

A:                       The mergers, taken together, will be treated for federal income tax purposes as a reorganization within the meaning of Section 368(a) of the Internal Revenue Code of 1986, as amended (the “Internal Revenue Code”).  It is a condition to the closing of the merger that Stinson Leonard Street LLP, counsel to Aslin Group, will have delivered an opinion to Aslin Group to the same effect at or prior to the effective time of the merger.

You may recognize gain, but you will not recognize loss, upon the exchange of your shares of Aslin Group common stock for shares of First Business common stock and cash.  If the sum of the fair market value of the First Business common stock and the amount of cash you receive in exchange for your shares of Aslin Group common stock exceeds the cost basis of your shares of Aslin Group common stock, you will recognize taxable gain equal to the lesser of the amount of such excess or the amount of cash you receive in the exchange.  Generally, any gain recognized upon the exchange will be capital gain, and any such capital gain will be long-term capital gain if you have established a holding period of more than one year for your shares of Aslin Group common stock.  Depending on certain facts specific to you, any gain could instead be characterized as dividend income.

For a more detailed discussion of the material United States federal income tax consequences of the transaction, see “Material United States Federal Income Tax Consequences of the Mergers” beginning on page 49.

Tax matters are very complicated, and the consequences of the merger to any particular stockholder will depend on that stockholder’s particular facts and circumstances.  Accordingly, you are urged to consult your own tax advisor to determine your tax consequences from the merger.

Q:                      Do I have appraisal or dissenters’ rights?

A:                       Aslin Group stockholders are entitled to appraisal rights under Section 262 et seq. of the DGCL.  If you wish to assert appraisal rights, you must deliver to Aslin Group before the vote is taken written notice of your intent to demand payment for your shares if the proposed action is effectuated and you must not vote in favor of the proposed action.  The procedure for dissenting is described in more detail in “The Merger” section under the heading “Appraisal Rights”.

First Business shareholders are not entitled to any dissenters’ or appraisal rights.

Q:                      Should I send in my stock certificates now?

A:                       No.  Please do not send your stock certificates with your proxy card.  If you are a holder of Aslin Group common stock, prior to the effective time of the merger, you will receive written instructions from Computershare Investor Services, Inc., the exchange agent in connection with the merger, regarding how to exchange your stock certificates for First Business common stock.

First Business shareholders will not be required to exchange or take any other action regarding their stock certificates in connection with the merger.  First Business shareholders holding stock certificates should keep their stock certificates both now and after the merger is completed.

Q:                      Whom should I contact if I have any questions about the proxy materials or the special meeting?

A:                       If you have any questions about the merger or any of the proposals to be considered at the special meeting, need assistance in submitting your proxy or voting your shares or need additional copies of this proxy statement/prospectus or the enclosed proxy card, you should contact Aslin Group.

Aslin Group, Inc., Attn: Corporate Secretary
11300 Tomahawk Creek Parkway, Suite 100
Leawood, KS 66211
Telephone: (913) 681-2223

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SUMMARY

This summary highlights selected information from this proxy statement/prospectus.  It may not contain all of the information that is important to you.  We urge you to carefully read the entire document and the other documents to which we refer you in order to fully understand the merger and the related transactions.  See “Where You Can Find More Information” on page 74 of this proxy statement/prospectus.  Each item in this summary refers to the page of this proxy statement/prospectus on which that subject is discussed in more detail.

The Companies

First Business Financial Services, Inc.

First Business is a registered bank holding company incorporated in 1986 under the laws of the State of Wisconsin and is engaged in the commercial banking business through its wholly-owned banking subsidiaries, First Business Bank and First Business Bank — Milwaukee (the “First Business Banks”).  All of its operations are conducted through the First Business Banks and certain subsidiaries of First Business.  The First Business Banks operate as business banks focusing on delivering a full line of commercial banking products and services tailored to meet the specific needs of small- and medium-sized businesses, business owners, executives, professionals and high net worth individuals.  First Business does not utilize a branch network to attract retail clients.

First Business’ common stock is traded on The NASDAQ Global Select Market under the symbol “FBIZ”.

First Business’ principal executive office is located at 401 Charmany Drive, Madison, Wisconsin, and its telephone number is (608) 238-8008.  First Business’ internet address is www.firstbusiness.com.  Additional information about First Business is included under “First Business,” “Where You Can Find More Information” and “Incorporation of Certain Documents by Reference” included elsewhere in this proxy statement/prospectus.

Aslin Group, Inc.

Aslin Group is a bank holding company headquartered in Leawood, Kansas.  Aslin Group’s principal business activities are conducted through its full-service, commercial bank subsidiary, Alterra Bank, a Kansas state-chartered bank with deposits insured by the FDIC.  Alterra Bank has two facilities in Kansas.  Like First Business, Alterra Bank operates an entrepreneurial business banking franchise, providing financing to small to middle market businesses seeking commercial term loans, commercial real estate loans and commercial lines of credit, as well as offering private banking services to individuals.  In addition, Alterra Bank is the number one most active U.S. Small Business Administration lender in the Kansas City SBA district.  Alterra Bank had $223 million in assets, including $184 million in loans, as well as $192 million in deposits, as of May 31, 2014.

Aslin Group’s common stock is not listed on an exchange or quoted on any automated services, and there is no established trading market for shares of Aslin Group common stock.

Aslin Group’s principal office is located at 11300 Tomahawk Creek Parkway, Suite 100, Leawood, KS 66211, and its telephone number at that location is (913) 681-2223.  Aslin Group’s internet address is www.alterrabank.com.  Additional information about Aslin Group is included under “Aslin Group” included elsewhere in this proxy statement/prospectus.

AGI Acquisition Corp.

AGI Acquisition Corp., which we refer to as “Acquisition Sub,” is a Delaware corporation that was formed to facilitate transactions contemplated by the Agreement and Plan of Merger dated as of May 22, 2014 (the “Merger Agreement”), and is a wholly-owned subsidiary of First Business.  Acquisition Sub will not conduct any activities other than those contemplated by the Merger Agreement.

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The Mergers

The Merger Agreement provides that, subject to its terms and conditions and in accordance with Delaware law, Acquisition Sub will merge with and into Aslin Group, with Aslin Group being the surviving corporation in the merger and thereby becoming a wholly-owned subsidiary of First Business.  This transaction is referred to in this proxy statement/prospectus as the “merger”.  Immediately following the merger and as part of a single integrated transaction, Aslin Group will be merged with and into First Business, with First Business being the surviving corporation in that second-step merger, referred to as the “second merger”.  The merger and the second merger are together referred to as the “mergers”.

First Business and Aslin Group expect the mergers contemplated by the Merger Agreement, taken together, to be a tax-free transaction for Aslin Group stockholders except as provided in “Material United States Federal Income Tax Consequences of the Mergers”.

Merger Consideration

At the effective time of the merger, each share of Aslin Group common stock issued and outstanding immediately prior to the effective time (other than shares of Aslin Group common stock owned by First Business or its subsidiaries, or shares of Aslin Group common stock held by stockholders that have validly exercised appraisal rights under the DGCL with respect to such shares) will cease to be outstanding and will be converted into the right to receive per share consideration valued at $14,435.59, which will be payable in (i) an amount of cash equal to $6,496.02, and (ii) a number shares of First Business common stock having a value of $7,939.57.  The number of shares of First Business common stock that each share of Aslin Group common stock will have the right to receive as the Stock Amount will equal $7,939.57 divided by the Bloomberg VWAP of the First Business common stock; provided, however, that if the number of shares as so calculated (1) is greater than 233.5154, such number will be reduced to 233.5154, or (2) is less than 155.6766, such number will be increased to 155.6766.  As a result, if the Bloomberg VWAP of the First Business common stock is less than $34.00, the value of the Stock Amount will be less than $7,939.57, and if the Bloomberg VWAP exceeds $51.00, the value of the Stock Amount will be greater than $7,939.57.  Cash will be paid in lieu of issuing fractional shares of First Business common stock.

Recommendation of Aslin Group’s Board of Directors

Aslin Group’s board of directors recommends that holders of Aslin Group common stock vote “FOR” the Merger Proposal and 280G Proposal.  For further discussion of Aslin Group’s reasons for the merger and the recommendations of Aslin Group’s board of directors, see “The Merger—Background of the Merger” and “The Merger—Aslin Group’s Reasons for the Merger and Recommendation of Aslin Group’s Board of Directors”.

Interests of Aslin Group Directors and Executive Officers in the Merger

Certain of Aslin Group’s directors and executive officers have interests in the merger as individuals in addition to, or different from, their interests as stockholders of Aslin Group, including, but not limited to, (i) potential payments under their employment agreements, (ii) continuation of employment after the merger, and (iii) accelerated vesting of options and restricted stock.

In connection with the merger, First Business has entered into employment-related agreements with certain executive officers of Aslin Group and Alterra Bank, including Pamela Berneking, Kent Brown, Doug Hoelscher, Jason Moxness, and Tim Gervy.

Certain directors and officers of Aslin Group have options that entitle them to purchase, in the aggregate, up to 45.5 shares of Aslin Group’s common stock and 66 shares of Aslin Group’s common stock are subject to a warrant held by Malcolm M. Aslin, the Chairman and CEO of Aslin Group.  Any outstanding options that are not vested will become immediately vested in connection with the merger.  Under the terms of the Merger Agreement, all such outstanding options already vested or vesting as a result of a change in control pursuant to any incentive compensation plan, including the Aslin Group 2010 Equity Incentive Plan, will be exercised as of the effective time of the merger or will expire, and the shares issuable upon exercise thereof will be exchanged for shares of First Business common stock pursuant to the Merger Agreement.

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In addition, certain officers of Aslin Group hold restricted shares of Aslin Group common stock.  All of the 30.75 outstanding unvested shares of Aslin Group restricted stock will vest on the effective date of the merger, and will also be converted into cash and shares of First Business common stock pursuant to the Merger Agreement.

For further discussion of the interests of Aslin Group’s directors and executive officers in the merger, see “The Merger— Interests of Aslin Group Directors and Executive Officers in the Merger”.

Stockholder Voting Agreement

In order to induce First Business to enter into the Merger Agreement, certain stockholders of Aslin Group who own, in the aggregate, 63.857 percent of the outstanding shares of Aslin Group common stock as of the record date, have each agreed that at any meeting of the stockholders of Aslin Group or in connection with any written consent of the stockholders of Aslin Group, such stockholder will vote all shares of Aslin Group common stock held of record or beneficially owned by such stockholder (to the extent the stockholder has the right to vote or direct the voting of such shares) in favor of the Merger Agreement and take certain other actions.  See “Aslin Group Special Meeting of Stockholders — Stockholder Voting Agreement”.

Appraisal Rights

The Aslin Group stockholders are entitled to appraisal rights under Section 262 et seq. of the DGCL.  Those rights, if properly exercised, will allow a stockholder who does not wish to accept the consideration provided for by the Merger Agreement instead to obtain payment of the fair value of the stockholder’s shares of Aslin Group common stock.  If you wish to assert appraisal rights, you must deliver to Aslin Group before the vote is taken written notice of your intent to demand payment for your shares if the proposed action is effectuated and you must not vote in favor of the proposed action.  The procedure for dissenting is described in more detail in “The Merger” section under the heading “Appraisal Rights”.

First Business shareholders are not entitled to any appraisal or dissenters’ rights.

Regulatory Matters

Each of First Business and Aslin Group has agreed to use its reasonable best efforts to obtain all regulatory approvals required to complete the merger and the other transactions contemplated by the Merger Agreement.  These approvals include approval from the Board of Governors of the Federal Reserve System, which is referred to as the “Federal Reserve”, and the Office of the State Bank Commissioner of Kansas, which is referred to as the “Kansas Bank Commissioner”.  First Business has filed all applications and notifications necessary to obtain these regulatory approvals.  There can be no assurance that such approvals will be received on a timely basis or at all, or as to the ability of First Business and Aslin Group to obtain the approvals on satisfactory terms or that there will be no litigation challenging such approvals.  See “Terms of the Merger Agreement — Regulatory Matters”.

Conditions to Completion of the Merger

Currently, First Business and Aslin Group expect to complete the merger in late 2014.  As more fully described in this proxy statement/prospectus and in the Merger Agreement, the completion of the merger depends on a number of conditions being satisfied or, where legally permissible, waived.  We cannot provide assurance as to when or if all of the conditions to the merger can or will be satisfied or waived by the appropriate party.

Termination of the Merger Agreement

As more fully described in this proxy statement/prospectus and in the Merger Agreement, the Merger Agreement can be terminated by either party at any time before completion of the merger under certain circumstances, including, without limitation:

·                  by mutual written consent;

·                  if the merger has not been consummated by March 31, 2015, unless certain conditions are met;

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·                  if a governmental authority has taken action to restrain, enjoin or otherwise prohibit the mergers; or

·                  if the Requisite Vote is not obtained, with certain exceptions.

As more fully described in this proxy statement/prospectus and in the Merger Agreement, the Merger Agreement can be terminated by Aslin Group at any time before completion of the merger under certain circumstances, including, without limitation:

·                  upon certain types of breach of the Merger Agreement by First Business;

·                  if any of the closing conditions to the obligations of Aslin Group to effect the merger have not been satisfied or waived;

·                  if Aslin Group opts to enter into a definitive agreement with respect to a Superior Offer (as defined in the Merger Agreement), after complying with its obligations related to the non-solicitation of alternative business combination transactions; or

·                  if there has been a First Business material adverse effect.

As more fully described in this proxy statement/prospectus and in the Merger Agreement, the Merger Agreement can be terminated by First Business at any time prior to completion of the merger under certain circumstances, including, without limitation:

·                  upon certain types of breach of the Merger Agreement by Aslin Group;

·                  if there is a Change of Recommendation (as defined in the Merger Agreement) or if Aslin Group materially violates or breaches its non-solicitation obligations relating to alternative business combination transactions;

·                  if any of the closing conditions to the obligations of First Business to effect the merger have not been satisfied or waived; or

·                  if there has been a Aslin Group material adverse effect.

Expenses and Termination Fees

The Merger Agreement provides that, in the event of termination of the Merger Agreement (i) by First Business if there is a Change of Recommendation or if Aslin Group shall have materially violated or breached its obligations not to solicit proposals relating to alternative business combination transactions, (ii) by Aslin Group in order to enter into a definitive agreement with respect to an unsolicited Superior Offer (as defined in the Merger Agreement), or (iii) by either party if the Requisite Vote of Aslin Group’s stockholders is not obtained at the Aslin Group stockholders’ meeting and there has been a Change of Recommendation, then Aslin Group will pay a termination fee of $1.2 million to First Business within two business days after such termination.

Except for the registration fee and other fees paid to the Securities and Exchange Commission, referred to as the “SEC”, in connection with the merger, which will be paid by First Business, and any termination fee, which will be paid by Aslin Group, all fees and expenses incurred in connection with the merger (including the costs and expense of printing and mailing this proxy statement/prospectus) will be paid by the party incurring such fees or expenses.

Matters to Be Considered at the Special Meeting

Aslin Group stockholders will be asked to vote on the following proposals:

1.              Approval of the Merger Proposal.

2.              Approval of the 280G Proposal.

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Approval of the Merger Proposal is required for the completion of the merger.  Approval of the 280G Proposal is not a condition of the merger.  Aslin Group’s board of directors recommends that Aslin Group stockholders vote “FOR” the proposals described in this proxy statement/prospectus.  For further discussion of the special meeting, see “Special Meeting of Stockholders”.

Rights of Aslin Group Stockholders Will Change as a Result of the Merger

The rights of Aslin Group stockholders are governed by Delaware law and Aslin Group’s certificate of incorporation and bylaws, and the rights of First Business shareholders are governed by Wisconsin law and First Business’ articles of incorporation and bylaws.  Upon the completion of the merger, Aslin Group stockholders will no longer have any direct interest in Aslin Group.  Aslin Group stockholders will only participate in the combined company’s future earnings and potential growth through their ownership of First Business common stock.  All of the other incidents of direct stock ownership in Aslin Group will be extinguished upon completion of the merger.  Following the merger, the rights of former Aslin Group stockholders will be governed by Wisconsin law and First Business’ articles of incorporation and bylaws.  Therefore, Aslin Group stockholders will have different rights once they become First Business shareholders.  See “Comparison of Rights of Holders of First Business and Aslin Group Common Stock”.

Price Range of Common Stock and Dividends

First Business common stock is listed on The NASDAQ Global Select Market under the symbol “FBIZ”.  The following table sets forth, for the periods indicated, the high and low reported sale prices per share of First Business common stock on the NASDAQ and cash dividends declared per share of First Business common stock.

First Business’ ability to pay dividends to its shareholders may be affected by both general corporate law considerations and policies of the Federal Reserve applicable to bank holding companies. As a Wisconsin corporation, First Business is subject to the limitations of the Wisconsin Business Corporation Law, which prohibit it from paying dividends if such payment would: (i) render it unable to pay its debts as they become due in the usual course of business, or (ii) result in its assets being less than the sum of its total liabilities plus the amount needed to satisfy the preferential rights upon dissolution of any shareholders with preferential rights superior to those shareholders receiving the dividend.

As a general matter, the Federal Reserve has indicated that the board of directors of a bank holding company should eliminate, defer or significantly reduce dividends to shareholders if: (i) the bank holding company’s net income available to shareholders for the past four quarters, net of dividends previously paid during that period, is not sufficient to fully fund the dividends; (ii) the prospective rate of earnings retention is inconsistent with the bank

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holding company’s capital needs and overall current and prospective financial condition; or (iii) such bank holding company will not meet, or is in danger of not meeting, its minimum regulatory capital adequacy ratios. The Federal Reserve also possesses enforcement powers over bank holding companies and their nonbank subsidiaries to prevent or remedy actions that represent unsafe or unsound practices or violations of applicable statutes and regulations. Among these powers is the ability to proscribe the payment of dividends by banks and bank holding companies.

Aslin Group’s common stock is not listed on an exchange or quoted on any automated services, and there is no established trading market for shares of Aslin Group common stock.  Also, all outstanding shares of Aslin Group common stock are subject to a Shareholders’ Agreement restricting the transfer of such shares (although the Shareholders’ Agreement is inapplicable to the merger and will terminate in accordance with its terms as a result of the merger). As a result, Aslin Group does not have sufficient data to estimate a market value of shares of Aslin Group common stock.  The holders of shares of Aslin Group common stock are entitled to dividends when, as and if declared by the board of directors, subject to the restrictions imposed by law, including the requirements of the Federal Reserve summarized above.  Since its formation in 2009, Aslin Group has never paid a dividend.  Under the Merger Agreement, Aslin Group is prohibited from declaring or paying any dividend on, or making any other distribution in respect of, its outstanding shares of capital stock prior to the effective date of the Merger Agreement.

Selected Historical Financial Data of First Business

The table below presents selected First Business historical financial data for the five years ended December 31, 2013, which are derived from its previously filed audited consolidated financial statements for those years and historical financial data for the six months ended June 30, 2014 and June 30, 2013, which are derived from its unaudited consolidated financial statements for those three months.

You should read the following table together with the historical financial information that First Business has presented in its prior SEC filings.  First Business has incorporated this material into this document by reference.  See “Incorporation of Certain Documents by Reference” on page 75.

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(1) Basic and diluted earnings per share reflect earnings per common share as calculated under the two-class method due to the existence of participating securities.

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RISK FACTORS

In addition to the other information contained in or incorporated by reference into this proxy statement/prospectus, including First Business’ Annual Report on Form 10-K for the fiscal year ended December 31, 2013, and the matters addressed under the caption “Cautionary Note Regarding Forward-Looking Statements,” Aslin Group stockholders should consider the matters described below carefully in determining whether to vote to approve the Merger Proposal.

Risk Factors Relating to the Merger

Because the market price of First Business common stock may fluctuate, you cannot be sure of the value of each share of First Business common stock that you will receive.

Upon completion of the merger, each share of Aslin Group common stock (other than shares of Aslin Group common stock owned by First Business or its subsidiaries, or shares of Aslin Group common stock held by stockholders that have validly exercised appraisal rights under the DGCL with respect to such shares) will be converted into the right to receive merger consideration consisting of shares of First Business common stock and cash, pursuant to the terms of the Merger Agreement.  The value of each share of First Business common stock to be received by Aslin Group stockholders will be based on the volume-weighted average closing price of First Business common stock on NASDAQ according to the Bloomberg VWAP Price and Volume Dashboard during the 10 consecutive trading days ending on and including the third trading day immediately prior to the date the merger closes, ranging between $34.00 per share and $51.00 per share. The volume-weighted average closing price may vary from the closing price of First Business common stock on the date we announced the merger, on the date that this proxy statement/prospectus was mailed to First Business shareholders and Aslin Group stockholders, on the date of the special meeting of the Aslin Group stockholders, on the date the merger is completed, and at any time after the merger is completed. If the Bloomberg VWAP of the First Business common stock is less than $34.00, the value of the Stock Amount will be less than $7,939.57, and if the Bloomberg VWAP exceeds $51.00, the value of the Stock Amount will be greater than $7,939.57. Stock price changes may result from a variety of factors, including general market and economic conditions, changes in the companies’ respective businesses, operations and prospects, and regulatory considerations, among other things.  Many of these factors are beyond the control of First Business.  Aslin Group stockholders should obtain current market quotations for shares of First Business common stock before voting their shares at the special meeting.

First Business may fail to realize all of the anticipated benefits of the merger.

The success of the merger will depend, in part, on First Business’ ability to successfully combine the First Business and Aslin Group organizations.  If First Business is not able to achieve this objective, the anticipated benefits of the merger may not be realized fully or at all or may take longer than expected to be realized.

First Business and Aslin Group have operated and, until the completion of the merger, will continue to operate, independently.  It is possible that the integration process or other factors could result in the loss or departure of key employees, the disruption of the ongoing business of Aslin Group or inconsistencies in standards, controls, procedures and policies.  It is also possible that clients, customers, depositors and counterparties of Aslin Group could choose to discontinue their relationships with the combined company post-merger because they prefer doing business with Aslin Group or for any other reason, which would adversely affect the future performance of the combined company.  These transition matters could have an adverse effect on each of First Business and Aslin Group during the pre-merger period and for an undetermined period of time after the completion of the merger.

The results of operations of First Business after the mergers may be affected by factors different from those currently affecting the results of operations of First Business and Aslin Group.

The businesses of First Business and Aslin Group differ in certain respects and, accordingly, the results of operations of the combined company and the market price of the combined company’s common stock may be affected by factors different from those currently affecting the independent results of operations of First Business and Aslin Group.  For a discussion of the business of First Business and certain factors to be considered in connection with First Business’ business, see “First Business” and the documents incorporated by reference in this proxy statement/prospectus and referred to under “Incorporation of Certain Documents by Reference”.  For a discussion of the

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business of Aslin Group and certain factors to be considered in connection with Aslin Group’s business, see “Information Concerning Aslin Group”.

The Merger Agreement limits Aslin Group’s ability to pursue an alternative transaction and requires Aslin Group to pay a termination fee under certain circumstances relating to alternative acquisition proposals.

The Merger Agreement prohibits Aslin Group from initiating, soliciting or taking any action to facilitate or encourage, directly or indirectly, any inquiries or the making or submission of any proposal or offer with respect to any acquisition transaction, or engaging in any negotiations concerning, an acquisition proposal, subject to exceptions set forth in the Merger Agreement.  The Merger Agreement also provides for the payment by Aslin Group to First Business of a termination fee of $1,200,000 if the Merger Agreement is terminated as a result of a breach of those provisions. These provisions may discourage a potential competing acquirer that might have an interest in acquiring Aslin Group from considering or proposing such an acquisition.  See “The Merger Agreement—Termination; Termination Fee” included elsewhere in this proxy statement/prospectus.

The merger is subject to the receipt of consents and approvals from governmental entities that may impose conditions that could have an adverse effect on the combined company following the merger.

Before the merger may be completed, approvals must be obtained from the Board of Governors of the Federal Reserve System and the Office of the State Bank Commissioner of Kansas.  These governmental entities may impose conditions on the granting of such approvals and consents.  Although First Business and Aslin Group do not currently expect that any such material conditions or changes would be imposed, there can be no assurance that they will not be, and such conditions or changes could have the effect of delaying completion of the merger or imposing additional costs or limiting the revenues of the combined company following the merger, any of which might have an adverse effect on the combined company following the merger.  In addition, each of First Business and Aslin Group has agreed to take certain actions prior to the closing of the merger.  Such actions may entail costs and may adversely affect First Business, Aslin Group, or the combined company following the merger.

The merger is subject to certain closing conditions that, if not satisfied or waived, will result in the merger not being completed, which could materially and adversely affect the business, financial condition and results of operations of First Business or Aslin Group.

The merger is subject to customary conditions to closing, including the receipt of required regulatory approvals and approval of the Aslin Group stockholders.  If any condition to the merger is not satisfied or waived, to the extent permitted by law, the merger will not be completed.  In addition, First Business and Aslin Group may terminate the Merger Agreement under certain circumstances even if the Merger Agreement is approved by Aslin Group stockholders.  If First Business and Aslin Group do not complete the merger, the trading price of First Business common stock may decline to the extent that the current price reflects a market assumption that the merger will be completed.  In addition, neither company would realize any of the expected benefits of having completed the merger.  If the merger is not completed and Aslin Group’s board of directors seeks another merger or business combination, Aslin Group stockholders cannot be certain that Aslin Group will be able to find a party willing to offer equivalent or more attractive consideration than the consideration First Business has agreed to provide in the merger.  If the merger is not completed, additional risks could materialize, which could materially and adversely affect the business, financial condition and results of operations of First Business or Aslin Group.  For more information on closing conditions to the Merger Agreement, see “The Merger Agreement—Conditions to the Merger” included elsewhere in this proxy statement/prospectus.

The combined company expects to incur substantial expenses related to the merger.

The combined company expects to incur substantial expenses in connection with completing the merger.  Although First Business and Aslin Group have assumed that a certain level of transaction and combination expenses would be incurred, there are a number of factors beyond their control that could affect the total amount or the timing of their combination expenses.  Many of the expenses that will be incurred, by their nature, are difficult to estimate accurately at the present time.  Due to these factors, the transaction and integration expenses associated with the merger could, particularly in the near term, exceed the savings that the combined company expects to achieve from the elimination of duplicative expenses and the realization of economies of scale and cost savings related to the combination of the businesses following the completion of the merger.  As a result of these expenses, both First

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Business and Aslin Group expect to take charges against their earnings before and after the completion of the merger.  The charges taken in connection with the merger are expected to be significant, although the aggregate amount and timing of such charges are uncertain at the present time.

Shares of First Business common stock to be received by Aslin Group stockholders as a result of the merger will have rights different from the shares of Aslin Group common stock.

Upon completion of the merger, the rights of former Aslin Group stockholders who receive First Business common stock in the merger and thereby become First Business shareholders will be governed by the articles of incorporation and bylaws of First Business.  The rights associated with Aslin Group common stock are different from the rights associated with First Business common stock.  See “Comparative Rights of Stockholders” beginning on page 56 for a discussion of the different rights associated with First Business common stock.

Certain Aslin Group directors and officers may have interests in the merger different from the interests of Aslin Group stockholders.

In considering the recommendation of the board of directors of Aslin Group, Aslin Group stockholders should be aware that certain directors and executive officers of Aslin Group and Alterra Bank have interests in the merger that may differ from, or may be in addition to, the interests of Aslin Group stockholders generally.  The board of directors of Aslin Group was aware of these interests and considered them, among other matters, when it adopted the Merger Agreement and in making its recommendations that the Aslin Group stockholders approve the Merger Proposal.  These interests include:

·                  In connection with the merger, First Business has entered into employment-related agreements with various employees of Alterra Bank, including Pamela Berneking, who is also a director of Aslin Group.

·                  Upon completion of the merger, Pamela Berneking will continue as President and CEO of Alterra Bank.

·                  Certain Aslin Group directors and officers are entitled acceleration of vesting of stock options and shares of restricted stock immediately prior to the effective time of the Merger Agreement.

For a more complete description of the interests of Aslin Group directors and executive officers in the merger, see “The Merger—Interests of Aslin Group’s Directors and Executive Officers in the Merger”.

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CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTS

This document, including information incorporated by reference into this document, contains or may contain forward-looking statements about First Business, Aslin Group and the combined company which are within the meaning of the safe harbor provisions for forward-looking statements contained in the Private Securities Litigation Reform Act of 1995.  These forward-looking statements include statements with respect to the expected timing, completion and effects of the proposed merger and the financial condition, results of operations, plans, objectives, future performance and business of First Business, Aslin Group and the combined company, including statements preceded by, followed by or that include the words “believes,” “expects,” “anticipates” or similar expressions.  These forward-looking statements involve certain risks and uncertainties.  Factors that may cause actual results to differ materially from those contemplated by such forward-looking statements include, among others, those risks discussed above.  Further information on other factors which could affect the financial results of First Business after the merger are included in the SEC filings incorporated by reference into this document.  See “Incorporation of Certain Documents by Reference” on page 75.

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ASLIN GROUP SPECIAL MEETING OF STOCKHOLDERS

General

Aslin Group’s board of directors is using this proxy statement/prospectus to solicit proxies from the holders of shares of Aslin Group common stock for use at the special meeting.

Together with this proxy statement/prospectus, Aslin Group is also sending you a notice of the special meeting and a form of proxy that is solicited by Aslin Group’s board of directors.  The special meeting will be held on September 17, 2014 at 11300 Tomahawk Creek Parkway, Suite 100, Leawood, KS 66211, at 10:00 am Central Time. On       , 2014, Aslin Group commenced mailing this proxy statement/prospectus and the enclosed form of proxy to its stockholders entitled to vote at the special meeting.

Purpose of Special Meeting

At the special meeting, Aslin Group stockholders will be asked to:

1.             Approve the Merger Proposal.

2.             Approve the 280G Proposal.  Approval of the 280G Proposal is not a condition of the Merger.

Recommendation of Aslin Group’s Board of Directors

Aslin Group’s board of directors recommends that you vote “FOR” the proposals described in this proxy statement/prospectus. See “The Merger— Aslin Group Reasons for the Merger and Aslin Group Board Recommendation” on page 34.

Record Date and Quorum

The record date for determining the holders of Aslin Group stock entitled to receive notice of and to vote at the special meeting is the close of business on       , 2014.

As of the record date for the special meeting, there were        shares of Aslin Group common stock outstanding and entitled to vote at the special meeting held by        holders of record.  Each share of Aslin Group common stock entitles the holder to one vote at the special meeting on each proposal to be considered at the special meeting.

The representation (in person or by proxy) of holders of at least a majority of the votes entitled to be cast on each of the matters to be voted on at the special meeting constitutes a quorum for action on that matter at the special meeting.  All shares of Aslin Group common stock present in person or represented by proxy, including abstentions and broker non-votes, will be treated as present for purposes of determining the presence or absence of a quorum for all matters voted on at the special meeting.

Stockholder Voting Agreement

In order to induce First Business to enter into the Merger Agreement, certain stockholders of Aslin Group who own, in the aggregate, 63.857 percent of the outstanding shares of Aslin Group common stock as of the record date have each agreed in a Stockholder Voting Agreement, referred to as the “Voting Agreement”, that at any meeting of the stockholders of Aslin Group or in connection with any written consent of the stockholders of Aslin Group, each such stockholder will vote all shares of Aslin Group common stock held of record or beneficially owned by such stockholder (to the extent the stockholder has the right to vote or direct the voting of such shares) (a) in favor of the Merger Agreement and each of the other actions contemplated by the Merger Agreement to be taken by Aslin Group, and (b) against any proposal relating to any other acquisition proposal and against any action or agreement that would impede the Voting Agreement, or result in a breach in any respect of any covenant, representation or warranty or any other obligation or agreement of Aslin Group under the Merger Agreement or which would result in any of the closing conditions of the Merger Agreement not being fulfilled.

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Each stockholder who is a party to the Voting Agreement has agreed that except as contemplated by the Voting Agreement and the Merger Agreement, such stockholder shall not, directly or indirectly:

·                  transfer any shares beneficially owned by such stockholder without the prior written consent of Aslin Group, subject to certain limited exceptions;

·                  enter into any option or other contract with respect to any transfer of any or all of such shares or any interest therein except as permitted by the Voting Agreement;

·                  grant any proxy, power-of-attorney or other authorization or consent in or with respect to such shares except to vote the shares in accordance with the terms of the Voting Agreement;

·                  deposit the shares into a voting trust or enter into a voting agreement or arrangement; or

·                  subject to the Voting Agreement, take any other action that would make any representation or warranty of such stockholder contained in the Voting Agreement untrue or incorrect in any material respect or in any way restrict, limit or interfere in any material respect with the performance of such stockholder’s obligations under the Voting Agreement or the transactions contemplated thereby or by the Merger Agreement.

The stockholders who are a party to the Voting Agreement have also agreed:

·                  not to encourage, solicit, initiate or participate in any way in any discussions or negotiations with, or provide any information to, or afford any access to the properties, books or records of the Aslin Group to, or otherwise take any other action to assist or facilitate, any other person or group (other than First Business or any affiliate or associate of First Business) concerning any acquisition proposal;

·                  to immediately cease any existing activities, discussions or negotiations conducted on or prior to the date of the Voting Agreement with respect to any acquisition proposal; and

·                  to immediately communicate to Aslin Group’s board of directors of the terms of any acquisition proposal (or any discussion, negotiation or inquiry with respect thereto) and the identity of the person making such acquisition proposal or inquiry which such stockholder may receive or of which such stockholder may become aware.

Notwithstanding the foregoing, in response to an unsolicited bona fide written Acquisition Proposal that did not result from Aslin Group’s breach of the Merger Agreement, each stockholder who is an officer or director of Aslin Group may take such actions (in such capacities) as are required to fulfill such officer’s or director’s fiduciary duties to Aslin Group and its stockholders, subject to the restrictions and conditions in the Merger Agreement.

The stockholders who are a party to the Voting Agreement also made certain representations and warranties to First Business.  Each stockholder who is a party to the Voting Agreement has waived any rights to exercise appraisal rights.

Each stockholder who is a party to the Voting Agreement has agreed to take all actions necessary to consummate and make effective the transactions contemplated by the Voting Agreement and the Merger Agreement.

The Voting Agreement will terminate upon the earlier of:

·                  the effective time of the merger; or

·                  the termination of the Merger Agreement.

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Required Vote; Effects of Abstention or Failure to Vote

Required Vote to Approve the Merger Proposal.  The affirmative vote of a majority of the outstanding shares of Aslin Group common stock entitled to vote is required to approve the Merger Proposal.  Therefore, assuming that a quorum is present, your abstention or failure to vote will have the same effect as a vote cast against this proposal.

Required Vote to Approve the 280G Proposal.  The affirmative vote of more than 75% of the issued and outstanding shares of Aslin Group common stock as of the record date, excluding those shares held by Pamela Berneking, is required to approve the 280G Proposal.  Therefore, assuming that a quorum is present, your abstention or failure to vote will have the same effect as a vote cast against this proposal.

Voting on Proxies; Incomplete Proxies

Giving a proxy means that an Aslin Group stockholder authorizes the persons named in the enclosed proxy card to vote its shares at the special meeting in the manner it directs.  An Aslin Group stockholder may vote by proxy or in person at the special meeting.  If you hold your shares of the Aslin Group common stock in your name as a stockholder of record, to submit a proxy, you, as an Aslin Group stockholder, may vote by completing and signing the accompanying proxy and returning it to Aslin Group as soon as possible in the enclosed postage-paid envelope.  When the accompanying proxy is returned properly executed, the shares of Aslin Group stock represented by it will be voted at the special meeting in accordance with the instructions contained on the proxy card.

If any proxy is returned without indication as to how to vote, the shares of Aslin Group common stock represented by the proxy will be voted as recommended by Aslin Group’s board of directors.  The proxy holders may use their discretion to vote on other matters properly before the special meeting.

If your shares are held in a street name, you should follow the instructions you receive from your broker in order to direct your broker how to vote, and you should also follow the instructions of your broker regarding revocation of proxies.

Every Aslin Group stockholder’s vote is important.  Accordingly, each Aslin Group stockholder should sign, date and return the enclosed proxy card, whether or not the Aslin Group stockholder plans to attend the special meeting in person.

Revocability of Proxies and Changes to an Aslin Group Stockholder’s Vote

An Aslin Group stockholder has the power to change its vote at any time before its shares of Aslin Group common stock are voted at the special meeting by:

·                  sending a notice of revocation to Aslin Group’s corporate secretary at 11300 Tomahawk Creek Parkway, Suite 100, Leawood, KS 66211 stating that you would like to revoke your proxy;

·                  sending a completed proxy card bearing a later date than your original proxy card; or

·                  attending the special meeting and voting in person if your shares of Aslin Group common stock are registered in your name rather than in the name of a broker, bank or other nominee, and you so request, although attendance at the special meeting will not by itself revoke a previously granted proxy.

If you choose the first method, you must take the described action no later than the beginning of the special meeting.  If you choose to send a completed proxy card bearing a date that is later than the date of your original proxy card, the new proxy card must be received before the beginning of the special meeting.  If you have instructed a bank, broker or other nominee to vote your shares of Aslin Group common stock, you must follow the directions you receive from your bank, broker or other nominee in order to change or revoke your vote.

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Solicitation of Proxies

The cost of solicitation of proxies will be borne by Aslin Group.  Aslin Group will reimburse brokerage firms and other custodians, nominees and fiduciaries of reasonable expenses incurred by them in sending proxy materials to the beneficial owners of common stock.  In addition to solicitations by mail, directors, officers and regular employees of Aslin Group may solicit proxies personally by telephone without additional compensation.

Attending the Special Meeting

All Aslin Group stockholders as of the record date, or their duly appointed proxies, may attend the special meeting.

If you hold your shares of Aslin Group common stock in your name as a stockholder of record and you wish to attend the special meeting, please bring your proxy and valid picture identification to the special meeting.

If your shares of Aslin Group common stock are held in “street name” in a stock brokerage account or by a bank or nominee and you wish to attend the special meeting, you need to bring a copy of a bank or brokerage statement to the special meeting reflecting your stock ownership as of the record date, along with a legal proxy, executed in your favor, from the broker, bank or other nominee that is the holder of record of your shares.  You should also bring valid picture identification.

PROPOSALS

Proposal No. 1: Merger Proposal

As discussed throughout this proxy statement/prospectus, Aslin Group is asking its stockholders to approve the Merger Proposal.  Holders of Aslin Group common stock should read carefully this proxy statement/prospectus in its entirety, including the appendices, for more detailed information concerning the Merger Agreement and the merger.  In particular, holders of Aslin Group common stock are directed to the Merger Agreement, a copy of which is attached as Appendix A to this proxy statement/prospectus.

Aslin Group’s board of directors recommends that Aslin Group stockholders vote “FOR” the Merger Proposal.

Proposal No. 2: 280G Proposal

Aslin Group is submitting for its stockholders’ approval certain payments and benefits that Pamela Berneking, President and Chief Executive Officer of Alterra Bank is eligible to receive pursuant to certain agreements with Aslin Group or First Business, but only if approved by the stockholders of Aslin Group.

Background

Section 280G of the Internal Revenue Code of 1986, as amended (the “Code”), and the regulations promulgated thereunder (collectively referred to as “Section 280G”) place limits on the amount of compensation and benefits that a corporation may provide to certain of its officers, highly compensated employees and significant stockholders in connection with a change in control of that corporation or its parent without incurring significant adverse tax consequences, as further described below. If such compensation and benefits exceed a certain amount, they are considered “parachute payments” subject to such adverse tax consequences unless (a) they are approved by stockholders holding more than 75% of the voting shares of the corporation undergoing the change in control immediately prior to the consummation of the merger as described below, and (b) prior to such vote, the material terms of the payments and benefits are disclosed to the stockholders entitled to vote.

The merger will constitute a change in control of Aslin Group, and certain payments and benefits to one of Alterra Bank’s officers and highly compensated employees, Pamela Berneking, that may be triggered in connection with or provided prior to or following the merger may constitute parachute payments under Section 280G.  Therefore, a portion of these potential payments and benefits to be received by Ms. Berneking in connection with

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the merger are being submitted to Aslin Group’s stockholders for approval.  Ms. Berneking has entered into a waiver agreement pursuant to which Ms. Berneking has agreed to forfeit certain payments and benefits; provided that if Aslin Group’s stockholders approve such payments and benefits in the manner described in Section 280G then such waived payments and benefits will be eligible to be provided to Ms. Berneking subject to the satisfaction of any other requirements applicable thereto.  If Aslin Group’s stockholders fail to approve the payments and benefits, then Ms. Berneking will not be able to receive or retain the waived payments and benefits.

Excess Parachute Payments

Under Section 280G, certain compensatory payments and benefits provided to any specified officer, highly compensated employee or significant stockholder of a corporation, also referred to as a “Disqualified Individual”, are treated as parachute payments if the total present value of the payments and benefits (as of the time of the ownership change) that are considered to be contingent on or closely related to a change in control of the corporation exceeds the threshold amount specified in the Code.  In general, the threshold amount for each Disqualified Individual is one dollar less than 300% of such Disqualified Individual’s average annual taxable compensation from his or her employer (or its predecessor entity or a related entity (in the case of Ms. Berneking, Alterra Bank)) for the last five completed calendar years preceding the year in which the change in control occurs (or, if fewer, for all completed calendar years in such Disqualified Individual’s period of employment, with compensation for any partial calendar year annualized).  Such average annual taxable compensation is referred to as the “Base Amount”.

If the threshold amount is exceeded, any parachute payments in excess of 100% of the Disqualified Individual’s Base Amount are treated as “excess parachute payments”.  Absent the approval of the stockholders of the contingent compensation or benefits which potentially could exceed the threshold amount, excess parachute payments are subject to the following tax penalties under Sections 280G and 4999 of the Code:

·                  Excess parachute payments are not deductible by the payor (in this case, Aslin Group, its subsidiaries or any of their successors, and First Business and its subsidiaries); and

·                  The Disqualified Individual must pay a nondeductible excise tax equal to 20% of the excess parachute payments.  This excise tax is in addition to regular income taxes.  Further, the payor (in this case, Aslin Group and/or First Business) may have a withholding and reporting obligation, depending on the type of payment.

Payments made under an agreement entered into within one year prior to a change in control are presumed to be contingent on the change in control.  In addition, the IRS regulations provide that an event occurring within the period beginning one year before and ending one year after the date of a change in control is presumed to be materially related to the change in control.  Pursuant to this rule, payments made upon a termination of employment or service that occurs within the one-year period following a change in control are generally treated as contingent payments. On the other hand, payments are not considered parachute payments if the taxpayer can show by clear and convincing evidence that they constitute reasonable compensation for personal services to be rendered by the Disqualified Individual or restrictive covenants that apply to the Disqualified Individual after the change in control or that they are otherwise not contingent on the change in control.

Stockholder Approval Exemption

Pursuant to a “Stockholder Approval Exemption” from the excess parachute payment rules provided by Section 280G(b)(5)(A)(ii) of the Code, a corporation undergoing a change in control that, immediately before the change in control, has no outstanding stock readily tradable on an established securities market or otherwise (i.e., a private corporation, like Aslin Group) is eligible to exclude disclosed payments and benefits from the excess parachute rules if (a) the payments and benefits are approved by the holders of stock possessing more than 75% of the voting power of all outstanding stock of the corporation entitled to vote immediately prior to the change in control, in a vote that is separate from, and not conditioned on, the vote to approve the change in control transaction and (b) before the vote, the material facts concerning the payments and benefits that, but for the Stockholder Approval Exemption, would be parachute payments, are adequately disclosed to all stockholders entitled to vote.  The stockholder vote must determine the right of the Disqualified Individual to receive or retain the payments and benefits.

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For purposes of calculating 75% of the voting power, shares held by or attributed to Ms. Berneking are disregarded (i.e. they are excluded from both the numerator and the denominator).

If a stockholder of the corporation undergoing the change in control is an “entity shareholder” (within the meaning of Treasury Regulations Section 1.280G-1, Q&A-7(b)(3)) and a “substantial portion” of the assets of the entity shareholder consists (directly or indirectly) of the stock of such corporation (i.e., the total fair market value of the stock held by the entity stockholder in such corporation equals or exceeds one third of the total gross fair market value of all the assets of the entity without regard to any liabilities associated with such assets) and the value of such stock held by such entity shareholder is greater than or equal to 1% of the total value of all the outstanding stock of such corporation, then the stockholder approval by the entity shareholder must be made by a separate vote of the persons who, immediately prior to the consummation of the change in control, hold more than 75% of the voting power of the entity shareholder.

Description of Potential Parachute Payments

A detailed description of potential payments and benefits, referred to as the “Potential Parachute Payments”, that might be received by Ms. Berneking in connection with the merger is set forth below.  Ms. Berneking has executed a waiver pursuant to which she has agreed to waive that portion of the Potential Parachute Payments that exceeds $1.00 less than three times her Base Amount, referred to as the “Excess Payment”, thereby reducing the aggregate amount of the payments and benefits Ms. Berneking would be entitled to receive in connection with the merger to an amount equal to $1.00 less than three times her Base Amount, referred to as the “Safe Harbor Amount”, if the requisite 75% stockholder approval is not obtained.

For purposes of this section, various assumptions have been made, as set forth below. In general, the analysis below assumes that every payment or benefit that could reasonably constitute a parachute payment is treated as such for purposes of the stockholder disclosure and vote.  The estimated amounts set forth below are based upon calculations of the estimated maximum amounts that might be considered parachute payments and do not necessarily reflect amounts that actually will be received by Ms. Berneking.  The one exception is the valuation of the First Business restricted stock, referred to as the “Restricted Stock”, that Ms. Berneking will receive upon the closing of the merger, which has a date of grant value of $200,000.  The value of the Restricted Stock for purposes of computing whether there are excess parachute payments, however, is the value of the Restricted Stock on the date it vests.  Since this amount is unknowable at this time, and could be greater or less than the value on the date of grant, the Restricted Stock has been valued at $200,000 for purposes of the calculations contained herein. Accordingly, all of the estimated amounts set forth in this section are based upon the assumed value of $200,000 for the Restricted Stock on the vesting date and an estimated closing and effective date of the merger of October 1, 2014.

Acceleration of Vesting of Seller’s Restricted Shares upon Consummation of the Merger

The vesting of restricted shares of Aslin Group’s common stock, which we refer to as the “Aslin Group Restricted Shares”, will fully accelerate in connection with the consummation of the merger.  For purposes of Section 280G, the acceleration of vesting of the 1.25 Aslin Group Restricted Shares held by Ms. Berneking will be considered a parachute payment with a value determined pursuant to the regulations promulgated under Section 280G.

Applying the Section 280G rules, the value of the Potential Parachute Payments with respect to the Aslin Group Restricted Shares held by Ms. Berneking, based on the acceleration of vesting of such shares, assuming that the per-share consideration in the merger will equal $14,435.59 per share, is estimated to be $559.

For purposes of all calculations in this section, it is assumed that the merger will occur on October 1, 2014. A different merger date could impact the value of the Potential Parachute Payments, but not to a material extent.

Guaranteed Minimum Bonus under the Berneking Employment Agreement

Ms. Berneking and First Business have entered into an Employment Agreement dated April 22, 2014, which will govern her employment as President and Chief Executive Officer of Alterra Bank after the merger occurs, which we refer to as the “Berneking Employment Agreement”.  The Berneking Employment Agreement will

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become null and void and of no further effect if the merger does not occur.  The Berneking Employment Agreement provides that Ms. Berneking will receive a minimum bonus for calendar year 2015 equal to 10% of her base salary.  Under the Berneking Employment Agreement, Ms. Berneking’s base salary is $200,000, although the amount of her base salary will be reviewed at least annually beginning in January of 2015, so her base salary could increase.  At the currently agreed base salary, the minimum bonus would be $20,000.  The bonus will be paid in accordance with the terms of First Business’ annual incentive bonus program.  The calculations hereunder assume that payment will be made on March 15, 2016, so the present value of the minimum bonus as of the date of the merger is $19,893.

Retention Amount under the Berneking Employment Agreement

Pursuant to the Berneking Employment Agreement, Ms. Berneking will be awarded $200,000 of Restricted Stock under First Business’ 2012 Equity Incentive Plan, which we refer to as the “Equity Plan”, which will vest on the first to occur of (a) the third anniversary of the merger if Ms. Berneking is employed by Alterra Bank on that date or (b) a Change in Control of First Business, as defined in the Equity Plan. As discussed above, the Restricted Stock is valued for purposes of all calculations contained herein at its date of grant value of $200,000.  In approving the payments described herein, the stockholders of Aslin Group are approving the payment to Ms. Berneking of the Restricted Stock at a future value that could be considerably greater than $200,000.

Severance Arrangements

Pursuant to the Berneking Employment Agreement, upon a termination of Ms. Berneking’s employment by Alterra Bank without “cause” or by Ms. Berneking for “good reason” (each as defined in the Berneking Employment Agreement) during the three-year term of the Berneking Employment Agreement, Ms. Berneking would become entitled to receive, subject to certain requirements (including the requirement to sign and not revoke a release of claims in favor of Alterra Bank), a cash severance payment of 18 months of her then base salary, paid in accordance with the payment schedule set out in the Berneking Employment Agreement.  The Berneking Employment Agreement also provides that Ms. Berneking and First Business will contemporaneously enter into an Executive Change-in-Control Agreement, which we refer to as the “CIC Agreement”, which also provides for severance if Ms. Berneking’s employment is terminated without cause or for good reason, both as defined in the CIC Agreement. The severance is (a) a cash amount equal to two times Ms. Berneking’s base salary, (b) a cash amount equal to her target bonus opportunity for the plan year in which the termination of employment occurs, prorated for the number of days worked in such year, and (c) subsidized health insurance coverage for up to 18 months. The Berneking Employment Agreement provides that in the event Ms. Berneking is entitled to severance payments under both the Berneking Employment Agreement and the CIC Agreement, she will receive the greater amount, but not both.  The severance under the CIC Agreement is the greater amount, and was the severance used for purposes of computing excess parachute payments hereunder.  Given that Ms. Berneking’s base salary and target bonus, as well as the cost of subsidized health insurance at the time of a termination of employment is unknown, this section has used the base salary and target bonus set forth in the Berneking Employment Agreement, and the current value of 18 months of subsidized health insurance, even though it is unknown what such amounts will be when her employment terminates.  The amounts were present-valued based on the payment schedule set forth in the CIC Agreement, which provides that cash severance (base and bonus) is paid in four payments at six-month intervals commencing after the six-month anniversary of her termination of employment and the subsidized health insurance will commence upon her termination of employment.  Her date of termination was assumed to be December 31, 2014, which would maximize the bonus component of the cash severance payment.  The present value of the cash component of her severance is $452,646, which is the present value of $460,000 (two times her base salary of $200,000 plus a target bonus of 30% of base salary or $60,000) given the assumptions regarding her termination date, the timing of the payments and the applicable interest rates.  The value of the health insurance, not present-valued given the likelihood of medical premiums increasing over time, is $14,270.

Summary

Based upon the assumption described above, the estimated aggregate present value of Ms. Berneking’s Potential Parachute Payments is $687,368.  Because Ms. Berneking’s Base Amount is $181,257, Ms. Berneking could have parachute payments of $543,770 or less without triggering any of the Section 280G excise taxes.  By voting to approve the amount of the Potential Parachute Payments in excess of $543,770, the Aslin Group’s stockholders are assuring that Ms. Berneking will be eligible to receive such excess payments (the “Excess Payments”), which are estimated to be $143,598 of additional payments and benefits, based upon the assumptions contained herein.  Ms.

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Berneking has waived her right to receive the Excess Payments, whatever their actual amount given the facts at the relevant times, if the Aslin Group’s stockholders do not approve the Excess Payments.

As described above, the $143,598 of Excess Payments is only an estimate given that there are many variables that are not known at the present time, including: (a) whether the Restricted Stock will vest, the vesting date, and the value of the Restricted Stock on the vesting date; (b) the date of Ms. Berneking’s termination of employment and the cause of termination; (c) whether Ms. Berneking will qualify for severance under the Berneking Employment Agreement or the CIC Agreement, and the amount of her severance, which is dependent on base salary, and in the case of the CIC Agreement, also target bonus amounts and health insurance subsidies, at a future date, and (d) future interest rates.

Voting Requirements and Board Recommendation

Ms. Berneking will be eligible to be paid or to receive the Excess Payments only if 75% of Aslin Group’s voting power, excluding the shares owned by Ms. Berneking, approve such Excess Payments.  If such approval is not obtained, Ms. Berneking will be entitled to receive or retain only that portion of her Potential Parachute Payments that totals $1.00 less than three times her Base Amount, or $543,770.  The consummation of the merger is not contingent upon the approval of the Excess Payments by Aslin Group’s stockholders.

The Board of Directors of Aslin Group unanimously recommends (except for Ms. Berneking, who abstained from the recommendation) that you vote “FOR” approval of Ms. Berneking’s Excess Payments, regardless of what their actual amount is subsequently determined to be.  By voting in favor of the Excess Payments, you are agreeing that Ms. Berneking is eligible to receive the Excess Payments whatever their ultimate amount (which may be more than the $143,598 which was determined based on the assumptions contained herein).

Other Matters to Come Before the Special Meeting

No other matters are intended to be brought before the special meeting by Aslin Group, and Aslin Group does not know of any matters to be brought before the special meeting by others.  If, however, any other matters properly come before the special meeting, the persons named in the proxy will vote the shares represented thereby in accordance with their judgment on any such matter.

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THE MERGER

The following is a discussion of the merger and the material terms of the Merger Agreement between First Business and Aslin Group.  You are urged to carefully read the Merger Agreement in its entirety, a copy of which is attached as Appendix A to this proxy statement/prospectus and incorporated by reference herein.  This summary may not contain all of the information about the Merger Agreement that is important to you.  Factual information about First Business and Aslin Group can be found elsewhere in this proxy statement/prospectus.  Additional factual information about First Business can be found in the public filings First Business makes with the SEC, as described in the section entitled “Where You Can Find More Information”.

Terms of the Merger

Transaction Structure.  First Business’ and Aslin Group’s boards of directors have each unanimously approved and adopted the Merger Agreement.  The Merger Agreement provides for the acquisition of Aslin Group by First Business through the merger of a direct wholly-owned subsidiary of First Business, with and into Aslin Group, with Aslin Group continuing as the surviving corporation.  Immediately following the merger and as part of a single integrated transaction, Aslin Group will be merged with and into First Business, with First Business being the surviving corporation in that second-step merger.

Merger Consideration.  At the effective time of the merger, each share of Aslin Group common stock issued and outstanding immediately prior to the effective time (other than shares of Aslin Group common stock owned by First Business or its subsidiaries, or shares of Aslin Group common stock held by stockholders that have validly exercised appraisal rights under the DGCL with respect to such shares) will cease to be outstanding and will be converted into the right to receive per share consideration valued at $14,435.59, which will be payable in (i) an amount of cash equal to $6,496.02, and (ii) a number shares of First Business common stock having a value of $7,939.57.  The number of shares of First Business common stock that each share of Aslin Group common stock will have the right to receive as the Stock Amount will equal $7,939.57 divided by the Bloomberg VWAP of the First Business common stock; provided, however, that if the number of shares as so calculated (1) is greater than 233.5154, such number will be reduced to 233.5154, or (2) is less than 155.6766, such number will be increased to 155.6766.  As a result, if the Bloomberg VWAP of the First Business common stock is less than $34.00, the value of the Stock Amount will be less than $7,939.57, and if the Bloomberg VWAP exceeds $51.00, the value of the Stock Amount will be greater than $7,939.57.  Cash will be paid in lieu of issuing fractional shares of First Business common stock. “Bloomberg VWAP” is defined as the volume-weighted average closing price of First Business common stock on NASDAQ according to the Bloomberg VWAP Price and Volume Dashboard during the 10 consecutive trading days ending on and including the third trading day immediately before the date the merger closes

As indicated in the previous paragraph, the number of shares of First Business common stock comprising the Stock Amount will vary based on the Bloomberg VWAP.  The following table illustrates, for a range of potentially applicable Bloomberg VWAPs, the number of shares of First Business common stock that would be exchanged for each share of Aslin Group common stock.  These numbers are calculated based on the assumption that 2,085.5 shares of Aslin Group common stock are outstanding immediately at the time of the merger.  This amount includes the shares of common stock that are expected to be issued upon the exercise of outstanding options and warrants on the effective date of the merger.

Stock Amount(1)

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(1)         The Stock Amount will be based on the actual Bloomberg VWAP, which will be computed on the third trading day immediately before the date the merger closes; the Bloomberg VWAPs shown on this table are for illustration only.  Cash will be paid in lieu of issuing fractional shares of First Business common stock.

Based on the assumption that approximately 389,596 shares of First Business common stock will be issued to Aslin Group stockholders based on a $42.50 Bloomberg VWAP, Aslin Group stockholders would own approximately 8.99% of First Business’ common stock after the merger is completed, ignoring any shares of First Business common stock they may already own.

Letters of Transmittal

At least ten days prior to the completion of the merger, the exchange agent, Computershare Investor Services, Inc., will send a letter of transmittal and instructions for surrendering certificates in exchange for the merger consideration and any cash in lieu of fractional shares of First Business common stock (as described below) to each holder of record of certificates which, as of the date the exchange agent sends such letter of transmittal and instructions, represented shares of Aslin Group common stock, whose shares were converted into the right to receive the merger consideration.

If any Aslin Group stockholder properly surrenders certificates to the exchange agent at least five business days prior to the closing date of the merger, then the exchange agent will mail or wire (as applicable) the merger consideration to such stockholder on the closing date.  If any Aslin Group stockholder properly surrenders certificates to the exchange agent at any time after five business days prior to the closing date of the merger, then the exchange agent will promptly, but no later than five business days after the receipt of the certificates, mail or wire (as applicable) the merger consideration to such stockholder.

If a certificate for Aslin Group common stock has been lost, stolen or destroyed, the exchange agent will issue the consideration properly payable under the Merger Agreement upon receipt of an affidavit as to that loss, theft or destruction and the posting of a bond at the expense of the stockholder to indemnify First Business and the exchange agent against any claim that may be made against it with respect to such certificate.

Cash in Lieu of Fractional Shares

No fractional shares of First Business common stock will be issued upon the surrender of certificates of Aslin Group common stock for exchange, and no dividend or distribution with respect to First Business common stock will be payable on or with respect to any fractional share, and such fractional share interests will not entitle the owner thereof to vote or to any other rights of a shareholder of First Business.  In lieu of the issuance of any such fractional share, First Business will pay to each former stockholder of Aslin Group who otherwise would be entitled to receive such fractional share an amount in cash (rounded to the nearest cent) determined by multiplying (i) the Bloomberg VWAP by (ii) the fraction of a share of First Business common stock which such holder would otherwise be entitled to receive, including any adjustments described above in the subsection titled “Merger Consideration”.

Dividends and Distributions

Until certificates representing shares of Aslin Group common stock are surrendered for exchange, any dividends or other distributions with a record date after the effective time of the merger with respect to First Business common stock into which such shares of Aslin Group common stock may have been converted will not be paid.  Following surrender of any such certificates, the record holder thereof will be entitled to receive, without interest, any dividends or other distributions with a record date after the effective time of the merger payable with respect to the whole shares of First Business common stock represented by such certificates and paid prior to the surrender date, and, at the appropriate payment date, the amount of dividends or other distributions payable with respect to shares of First Business common stock represented by such certificates with a record date after the effective time of the merger but before the surrender date and with a payment date after the surrender.

After the effective time of the merger, there will be no transfers on the stock transfer books of Aslin Group of any shares of Aslin Group common stock, other than to settle transfers that occurred prior to the effective time of the merger.  If certificates representing such shares are presented for transfer after the completion of the merger, they

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will be cancelled and exchanged for the merger consideration into which the shares represented by that certificate have been converted.

Appraisal Rights

Under Section 262 of the DGCL, any holder of Aslin Group common stock who does not wish to accept the merger consideration may dissent from the merger and elect to exercise appraisal rights.  A stockholder who exercises appraisal rights may ask the Delaware Court of Chancery to determine the fair value of his or her shares (exclusive of any element of value arising from the accomplishment or expectation of the merger), and receive payment of fair value in cash, together with a fair rate of interest, if any, provided that the stockholder complies with the provisions of Section 262 of the DGCL.

The following discussion is a summary of the law pertaining to appraisal rights under the DGCL.  The full text of Section 262 of the DGCL is attached to this information statement/prospectus as Appendix B.  All references in Section 262 of the DGCL to a “stockholder” and in this summary to a “stockholder” are to the record holder of the shares of Aslin Group common stock who asserts appraisal rights.

Section 262(d)(1) of the DGCL requires that, if a Merger Agreement was approved by a stockholder vote at a meeting, as opposed to stockholder consent under Section 228 of the DGCL, stockholders entitled to appraisal rights will be notified not less than 20 days prior to the meeting, and that appraisal rights are available for any or all shares of stock held by such stockholder.  A copy of Section 262 of the DGCL must be included with such notice.  As approval of the Merger Agreement by Aslin Group stockholders is being obtained at the meeting of the stockholders, this information statement/prospectus constitutes Aslin Group’s notice to its stockholders of the availability of appraisal rights in connection with the merger in compliance with the requirements of Section 262 of the DGCL.  The applicable statutory provisions are attached to this information statement/prospectus as Appendix B.  This summary of appraisal rights is not a complete summary of the law pertaining to appraisal rights under the DGCL and is qualified in its entirety by the text of Section 262 of the DGCL attached as Appendix B.  Any holder of Aslin Group common stock who wishes to exercise appraisal rights or who wishes to preserve the right to do so should review the following discussion and Appendix B carefully.  Failure to comply with the procedures of Section 262 of the DGCL, in a timely and proper manner, will result in the loss of appraisal rights.  If you lose your appraisal rights, you will be entitled to receive the merger consideration described in the Merger Agreement.

Stockholders wishing to exercise the right to dissent from the merger and seek an appraisal of their shares must do all of the following:

·                  The stockholder must deliver to Aslin Group a separate written demand for appraisal of his/her shares before the taking of the vote on the Merger Agreement at the meeting.

·                  The stockholder must not have voted in favor of the Merger Agreement and the transactions contemplated thereby.

·                  The stockholder must continuously hold the shares from the date of making the demand through the effective time of the merger.  A stockholder will lose appraisal rights if the stockholder transfers the shares before the effective time of the merger.

·                  The stockholder must file a petition in the Delaware Court of Chancery demanding a determination of the fair value of the shares within 120 days after the effective time of the merger.  The surviving company is under no obligation, and has no intention, to file any such petition.

Only a holder of record of shares of Aslin Group common stock issued and outstanding immediately prior to the effective time of the merger may assert appraisal rights for the shares of stock registered in that holder’s name.  A demand for appraisal must be executed by or on behalf of the stockholder of record, fully and correctly, as the stockholder’s name appears on the stock certificates.  The demand must reasonably inform Aslin Group of the identity of the stockholder and that the stockholder intends to demand appraisal of his or her common stock.  Stockholders who hold their shares in brokerage accounts or other nominee forms, and who wish to exercise appraisal rights, should consult with their brokers to determine the appropriate procedures for the nominee holder to make a demand for appraisal of those shares.  A person having a beneficial interest in shares held of record in the

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name of another person, such as a broker or nominee, must act promptly to cause the record holder to follow properly and in a timely manner the steps necessary to perfect appraisal rights.

A stockholder who elects to exercise appraisal rights under Section 262 of the DGCL should mail or deliver a written demand to Malcolm M. Aslin, Aslin Group, Inc., 11300 Tomahawk Creek Parkway, Suite 100, Leawood, Kansas 66211.

Within 10 days after the effective date of the merger, a second notice regarding the effective date of the merger will be sent by the surviving or resulting corporation to all such holders who have complied with Section 262(d)(1) and not voted in favor of the merger as of the date the merger has become effective.

Within 120 days after the effective time of the merger, but not later, either the surviving company or any dissenting stockholder who has complied with the requirements of Section 262 of the DGCL may file a petition in the Delaware Court of Chancery demanding a determination of the value of the shares of Aslin Group common stock held by all dissenting stockholders.  The surviving company is under no obligation, and has no intention, to file any such petition.  Stockholders who desire to have their shares appraised should initiate any petitions necessary for the perfection of their appraisal rights within the time periods and in the manner prescribed in Section 262 of the DGCL.

Within 120 days after the effective time of the merger, any stockholder who has complied with the provisions of Section 262 of the DGCL to that point in time may receive from the surviving company, upon written request, a statement setting forth the aggregate number of shares not voted in favor of the Merger Agreement and with respect to which Aslin Group has received demands for appraisal, and the aggregate number of holders of those shares.  The surviving company must mail this statement to the stockholder within 10 days of receipt of the request.

If any party files a petition for appraisal in a timely manner, the Delaware Court of Chancery will determine which stockholders are entitled to appraisal rights and may require the stockholders demanding appraisal who hold certificated shares to submit their stock certificates to the court for notation of the pendency of the appraisal proceedings and any stockholder who fails to comply with such direction may be dismissed from such proceedings.  If the stockholder fails to comply with the court’s direction, the court may dismiss the proceeding as to such stockholder.  The Delaware Court of Chancery will thereafter determine the fair value of the shares of Aslin Group common stock held by dissenting stockholders, exclusive of any element of value arising from the accomplishment or expectation of the merger, but together with a fair rate of interest, if any, to be paid on the amount determined to be fair value.

In determining the fair value, the Delaware Court of Chancery will take into account all relevant factors.  The Delaware Supreme Court has stated that “proof of value by any techniques or methods that are generally considered acceptable in the financial community and otherwise admissible in court” should be considered in the appraisal proceedings.  In addition, Delaware courts have decided that the statutory appraisal remedy, in cases of unfair dealing, may or may not be a dissenter’s exclusive remedy.  The Delaware Court of Chancery may determine the fair value to be more than, less than or equal to the consideration that the dissenting stockholder would otherwise receive under the Merger Agreement.  If no party files a petition for appraisal in a timely manner, then stockholders will lose the right to an appraisal, and will instead receive the merger consideration described in the Merger Agreement.

The Delaware Court of Chancery will determine the costs of the appraisal proceeding and will allocate those costs to the parties as the Delaware Court of Chancery determines to be equitable under the circumstances.  Upon application of a stockholder, the Delaware Court of Chancery may order all or a portion of the expenses incurred by any stockholder in connection with the appraisal proceeding, including reasonable attorneys’ fees and the fees and expenses of experts, to be charged pro rata against the value of all shares entitled to appraisal.

Stockholders should be aware that the fair value of their shares as determined under Section 262 of the DGCL could be greater than, the same as, or less than the merger consideration.  A fairness opinion of an investment banking firm does not in any manner address fair value under Section 262 of the DGCL.

Any stockholder who has duly demanded an appraisal in compliance with Section 262 of the DGCL may not, after the effective time of the merger, vote the shares subject to the demand for any purpose or receive any dividends

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or other distributions on those shares (except dividends or other distributions payable to holders of record of shares as of a record date prior to the effective time of the merger).

Any stockholder may withdraw a demand for appraisal and accept the merger consideration by delivering to the surviving company a written withdrawal of the demand for appraisal, except that (1) any attempt to withdraw made more than 60 days after the effective time of the merger will require written approval of the surviving company, and (2) no appraisal proceeding in the Delaware Court of Chancery will be dismissed as to any stockholder without the approval of the Delaware Court of Chancery, and may be conditioned on such terms as the Delaware Court of Chancery deems just.  If the stockholder fails to perfect, successfully withdraws or loses the appraisal right, the stockholder’s shares will be converted into the right to receive the merger consideration.

Failure to follow the steps required by Section 262 of the DGCL for perfecting appraisal rights may result in the loss of appraisal rights in which event you will be entitled to receive the consideration with respect to your dissenting shares in accordance with the Merger Agreement.  In view of the complexity of the provisions of Section 262 of the DGCL, if you are an Aslin Group stockholder and are considering exercising your appraisal rights under the DGCL, you should consult your own legal advisor.

This is not a complete statement of all applicable requirements and is qualified in its entirety by reference to Section 262 et seq. of the DGCL, which is reproduced in its entirety as Appendix B to this proxy statement/prospectus.

Regulatory Approvals

Each of First Business and Aslin Group has agreed to use its reasonable best efforts to obtain all regulatory approvals required to complete the merger and the other transactions contemplated by the Merger Agreement.  These approvals include approval from the Board of Governors of the Federal Reserve System and the Office of the State Bank Commissioner of Kansas.  First Business has filed all applications and notifications to obtain these regulatory approvals.

Board of Governors of the Federal Reserve System.  The transactions contemplated by the Merger Agreement are subject to approval by the Board of Governors of the Federal Reserve System pursuant to the Bank Holding Company Act of 1956, as amended.

Office of the State Bank Commissioner of Kansas.  The transactions contemplated by the Merger Agreement are subject to approval by the Office of the State Bank Commissioner of Kansas.

There can be no assurance that such approvals will be received on a timely basis or at all, or as to the ability of First Business and Aslin Group to obtain the approvals on satisfactory terms or that there will be no litigation challenging such approvals.  There can be no assurances that U.S. or state regulatory authorities will not attempt to challenge the merger on antitrust grounds or for other reasons, or, if such a challenge is made, as to the result of such challenge.  The parties’ obligations to complete the transactions contemplated by the Merger Agreement are subject to a number of conditions, including the receipt of all requisite regulatory approvals.

Accounting Treatment

First Business will account for the merger using the acquisition method of accounting, in accordance with current accounting guidance and United States generally accepted accounting principles.  The result of this is that the recorded assets and liabilities of First Business will be carried forward at their recorded amounts, the historical operating results will be unchanged for the prior periods being reported on and that the assets and liabilities of Aslin Group will be adjusted to fair value at the date of the merger. In addition, all identified intangibles will be recorded at fair value and included as part of the net assets acquired. To the extent that the purchase price, consisting of cash plus the number of shares of First Business common stock to be issued to former Aslin Group stockholders at fair value, exceeds the fair value of the net assets including identifiable intangibles of Aslin Group at the date of the merger, that amount will be reported as goodwill. In accordance with current accounting guidance, goodwill will not be amortized but will be evaluated for impairment annually. Identified intangibles will be amortized over their estimated lives. Further, the acquisition method of accounting results in the operating results of Aslin Group being included in the operating results of First Business beginning from the date of completion of the merger.

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Public Trading Market

First Business common stock is listed on The NASDAQ Global Select Market under the symbol “FBIZ”.  The First Business common stock issuable in the merger will be listed on The NASDAQ Global Select Market.

Resale of First Business Common Stock

All shares of First Business common stock received by Aslin Group stockholders in the merger will be freely tradable for purposes of the Securities Act of 1933, as amended (the “Securities Act”), and the Exchange Act, except for shares of First Business common stock received by any such holder who becomes an “affiliate” of First Business after completion of the merger, as defined in Rule 144 under the Securities Act.  This proxy statement/prospectus does not cover resales of shares of First Business common stock received by any person upon completion of the merger, and no person is authorized to make any use of this proxy statement/prospectus in connection with any resale.

Background of the Merger

The management of Aslin Group has from time to time explored and assessed, both internally and with outside advisors, and has discussed with the Aslin Group board of directors, various strategic options potentially available to Aslin Group.  These strategic discussions have focused on, among other things, available strategic transaction opportunities, the business and regulatory environment facing banks and financial institutions generally, and Aslin Group in particular, and the cost of additional capital for growth, as well as conditions and ongoing consolidation in the financial services industry.

As part of its ongoing strategic planning activities, First Business’ management and board of directors also considers acquisition opportunities, including the possible acquisition of another financial institution; regularly reviews the financial services industry environment, including the trend towards consolidation in the industry; and periodically discusses ways in which to enhance First Business’ shareholder value and competitive position.

In early 2013, management and the board of directors of Aslin Group considered the need for additional capital to support the planned growth of Alterra Bank.  The topic was discussed as part of the company’s budget and planning process and in the preparation of Aslin Group’s capital plan for 2014.  As a result of these discussions, Aslin Group’s management had discussions with a number of interested parties about a potential investment in Aslin Group.

Individual Investor.  In April of 2013, Aslin Group learned that a wealthy individual investor was interested in possibly investing in or acquiring Aslin Group and its subsidiary, Alterra Bank.  On May 20, 2013, the investor sent an unsolicited expression of interest letter to the board of directors of Aslin Group with a proposed cash purchase price per share for all outstanding shares.  On June 10, 2013, the CEO of Aslin Group responded to the investor with a detailed counter offer and proposed a higher purchase price.  At a board meeting held on July 22, 2013, the board of directors of Aslin Group appointed a committee of the board to negotiate with the investor.  For several weeks, the investor and members of the negotiating committee exchanged letters and emails regarding the valuation of Aslin Group and the terms of a potential acquisition.  They also negotiated and exchanged drafts of a confidentiality agreement and a letter of intent.

On August 20, 2013, Aslin Group and the investor entered into a Confidentiality, Non-Disclosure and Exclusivity Agreement, which included a 60-day exclusive negotiating period with the investor.  On August 21, 2013, the investor, Aslin Group and Alterra Bank entered into a letter of intent that included a purchase price per share that would be adjusted based upon the results of the investor’s due diligence on Alterra Bank’s loan portfolio.  During the next two months, the investor met with the President and Chief Executive Officer of Alterra Bank and conducted significant due diligence on Alterra Bank’s business and loan portfolio.  On September 12, 2013, the investor delivered a draft of a definitive merger agreement.  In October 2013, the negotiating committee held several teleconference meetings to discuss the price and terms offered by the investor.  Aslin Group and the investor negotiated through their counsel on pricing and certain material terms and conditions of the proposed acquisition.

The 60-day exclusive negotiating period expired on October 19, 2013, and the investor and the negotiating committee could not agree upon the purchase price for Aslin Group or the material terms and conditions of a

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proposed merger.  No merger agreement was ever signed and the letter of intent expired.  After an October 21, 2013 meeting with the investor, there were no ongoing communications or negotiations between Aslin Group and the investor.

At its October 21, 2013 meeting, the board of directors of Aslin Group again discussed the need for additional capital to support growth of Alterra Bank.  This discussion was concurrent with the development of Alterra Bank’s 2014 budget, which called for additional capital to be contributed by March 31, 2014.  Efforts to identify possible sources of that capital were led by the CEO of Aslin Group, who met with a number of existing and prospective stockholders in November and December of 2013.  Concurrently, management sought and received interest from possible buyers of subordinated debt as an alternative to an equity capital raise.

Late in the fourth quarter of 2013 and early in the first quarter of 2014, the CEO of Aslin Group had discussions and meetings with several out-of-state bank holding companies about a possible acquisition of Aslin Group and Alterra Bank.  Some of these discussions were facilitated via introductions made by a representative of Macquarie Capital (USA), Inc., which we refer to as Macquarie Capital. During this time, the CEO of Aslin Group discussed with two other investment bankers the expected valuation of Aslin Group, as well as possible strategic merger partners.  The board of directors of Aslin Group, however, made no decision to sell the company, and did not engage an investment advisor to market the company.

BHC A.  On December 12, 2013, the CEO of Aslin Group met with senior executives of an out-of-state bank holding company, which is referred to herein as “BHC A”.  Several telephone calls followed, and, on January 16, 2014, the CEO of Aslin Group and the President and Chief Executive Officer and another senior executive officer of BHC A met at Aslin Group’s headquarters in Leawood, Kansas.  At that meeting, BHC A delivered an indication of interest letter, dated January 15, 2014, to acquire all of the stock of Alterra Bank.  In a conference call held on January 27, 2014, the CEO of Aslin Group discussed the contents of the indication of interest letter with senior executives of BHC A.  Subsequently, a bank subsidiary of BHC A submitted a letter of intent, dated January 30, 2014, to acquire all of the outstanding capital stock of Aslin Group.  The CEO of Aslin Group responded with revised drafts of the letter of intent that provided for the proposed transaction to be structured as a cash-out merger of Aslin Group into an acquisition subsidiary of BHC A.  BHC A’s proposed acquisition of Aslin Group was not subject to any financing contingency.  In late January and early February 2014, the CEO of Aslin Group and the President and Chief Executive Officer of BHC A also negotiated the terms of a confidentiality agreement.

On February 4, 2014, Aslin Group and Alterra Bank entered into a confidentiality agreement with a bank subsidiary of BHC A.  During February 2014, management of Aslin Group and BHC A had discussions and meetings regarding Alterra Bank’s business and the proposed structure of a possible acquisition.  On February 19, 2014, four senior executives of BHC A met in Kansas City with the CEO of Aslin Group and the President and Chief Executive Officer of Alterra Bank to introduce her and to further discuss a potential strategic merger with Aslin Group.  On February 25, 2014, the President and Chief Executive Officer of Alterra Bank had all day meetings at the headquarters of BHC A.  As discussed further below, the board of directors of Aslin Group concluded that the price, terms and structure of BHC A’s offer (including fully-taxable cash consideration) were not as favorable to Aslin Group’s stockholders as the price, terms and structure offered by another interested party.  On or about March 4, 2014, the CEO of Aslin Group told BHC A that Aslin Group intended to pursue a transaction with another interested party.  No further significant discussions with BHC A occurred after March 5, 2014.

BHC B.  On December 27, 2013, the CEO of Aslin Group met with the CEO of another out-of-state bank holding company, which is referred to herein as “BHC B”.  On January 22, 2014, the CEO of Aslin Group met with senior executives of BHC B at the headquarters of Aslin Group.  On January 26, 2014, Aslin Group received an indication of interest letter from BHC B to acquire all of the outstanding stock of Alterra Bank.  BHC B’s proposed acquisition contained an express financing contingency.  BHC B also provided letters, both dated January 23, 2014, from two investment bankers who would advise BHC B and assist in a private placement of equity to partially finance the acquisition.  During late January 2014, the CEO of Aslin Group had calls with senior management of BHC B regarding its proposed valuation of Alterra Bank, and the amount of financing that would be required to consummate the transaction.  On February 4, 2014, the CEO of Aslin Group told BHC B that there were concerns about the financing contingency in BHC B’s offer, and Aslin Group was attempting to negotiate a transaction with another interested party.  No further significant discussions with BHC B occurred after February 4, 2014.

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First Business.  On December 17, 2013, a representative of Macquarie Capital discussed Aslin Group and Alterra Bank with the CEO of First Business, and provided publicly available financial information on Aslin Group and Alterra Bank.  In January 2014, a representative of Macquarie Capital discussed with the CEO of Aslin Group First Business’ unique business banking model and his belief that Alterra Bank would strategically fit well with First Business.  Macquarie Capital arranged an introduction of the President and Chief Executive Officer and the Chairman of First Business to the CEO of Aslin Group.  On February 12, 2014, the President and Chief Executive Officer and the Chairman of First Business met with the CEO of Aslin Group in Bonita Springs, Florida to discuss a potential strategic combination of First Business and Aslin Group.  On February 17, 2014, the President and Chief Executive Officer of Alterra Bank and the President and Chief Executive Officer of First Business met via videoconference.

On February 19, 2014 a special meeting of the First Business board of directors was convened and management provided updates to the First Business board of directors on several items including the Aslin Group acquisition opportunity.  Management and representatives from Keefe, Bruyette & Woods, which is referred to herein as KBW, provided an overview of the opportunity, including Aslin Group and Alterra Bank background information and history, management backgrounds, preliminary deal terms, information about the Kansas City and surrounding markets, terms of comparable transactions and initial impressions.  At this meeting, the First Business board of directors authorized the issuance of a non-binding letter of intent which would allow management an opportunity to continue due diligence.

First Business delivered a letter of intent, dated February 20, 2014, to acquire Aslin Group.  Over the next two weeks Aslin Group and First Business exchanged revised drafts of the letter of intent, and also negotiated a non-disclosure agreement.

On February 27, 2014, a mutual non-disclosure agreement was signed by First Business, Aslin Group and Alterra Bank, pursuant to which all parties agreed to maintain the confidentiality of any evaluation material provided by the other party.  Also, on February 27, 2014, the President and Chief Executive Officer of Alterra Bank had all-day meetings with First Business at its headquarters in Madison, Wisconsin.  Aslin Group, whose key business information (unlike First Business’ business information) is not periodically and publicly reported, provided First Business with detailed audited financial statements, copies of material agreements and other business and organizational information.

On March 4, 2014, all members of the board of directors of Aslin Group participated in a joint conference call.  The President and Chief Executive Officer of Alterra Bank reported on her meetings with BHC A and First Business, expressed her views on the relative strengths of BHC A and First Business, and indicated the reasons for her preferences for a merger with First Business.  The board of directors analyzed the letters of intent submitted by BHC A and First Business, and the key terms of and conditions underlying both offers.  The board of directors noted that First Business’ proposed purchase price range was higher than the proposed purchase prices offered or discussed with the individual investor, BHC A and BHC B.  The board of directors discussed a number of factors favoring First Business’ offer, including:  First Business’ purchase price range, perceived strategic and cultural fit, benefits to customers and employees of continuing the business bank model, the continued existence (after the merger) of Alterra Bank under its own charter, First Business’ requirement that certain key employees of Alterra Bank sign employment agreements to continue working after the merger, and the high likelihood of closing a transaction with First Business.  The board of directors directed the CEO of Aslin Group to sign the letter of intent with First Business.

On March 7, 2014 at its regular board meeting, the First Business board of directors reestablished a Capital and Acquisitions Committee, which is referred to herein as the Committee, to review the proposed transaction and make recommendations to the board.  At that meeting, the board of directors of First Business authorized the President and Chief Executive Officer of First Business to sign a letter of intent to acquire Aslin Group.

On March 7, 2014, First Business, Aslin Group and Alterra Bank signed a letter of intent for First Business to acquire Aslin Group via a reverse triangular merger for a combination of stock and cash consideration.  The executed letter of intent contemplated a price range of $28.5 million to $30.0 million of aggregate consideration, with 55% of the consideration in the form of First Business common stock and 45% of the consideration in cash.  The letter of intent included a 60-day exclusivity period.

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Over the course of the subsequent weeks, representatives of Aslin Group and First Business conducted mutual due diligence involving senior executives from both companies as well as their outside legal and financial advisors.  On March 12, 2014, the President and Chief Executive Officer of First Business came to Kansas City to meet with the President and Chief Executive Officer and senior leadership team of Alterra Bank.  During March 2014, the parties and their outside counsel began discussing the material terms on which a transaction could be reached, including the conditions to a potential transaction, and other significant provisions.  In the course of these conversations First Business indicated, among other things, that its indication of interest was contingent upon the execution of a stockholder voting agreement with certain significant stockholders of Aslin Group, and Aslin Group directors, certain employment agreements, and a noncompetition agreement with the CEO of Aslin Group.  On March 29, 2014, the parties executed an amendment to the letter of intent to extend the exclusivity period for an additional 30 days.  During April and May of 2014, the CEO of Aslin Group continued to update members of the board of directors of Aslin Group on the progress of due diligence and negotiations with First Business.

The Committee met with management and representatives of KBW on April 10, 2014, and again on April 22, 2014, to review and discuss the proposed transaction with Aslin Group.  At the April 22, 2014 meeting, the Committee reviewed a summary of potential merger agreement terms and authorized management to begin negotiating the terms of a merger agreement with Aslin Group.

On April 25, 2014, counsel to First Business delivered a first draft of Merger Agreement to Aslin Group.  Over the next three weeks, counsel for First Business and counsel for Aslin Group exchanged several drafts of the Agreement and Plan of Merger.  In addition to negotiating the definitive Merger Agreement, the parties also negotiated the related transaction documents, including the Stockholder Voting Agreement and a Non-Disclosure, Non-Solicitation and Non-Competition Agreement for the CEO of Aslin Group.  In addition, First Business negotiated conditional employment agreements with the President and Chief Executive Officer and four other officers of Alterra Bank to continue their employment with Alterra Bank after the consummation of the merger.  The CEO of Aslin Group and the President and Chief Executive Officer of First Business ultimately agreed to recommend to their respective boards of directors a transaction in which First Business would acquire Aslin Group for aggregate consideration of approximately $30 million, consisting of 55% First Business stock and 45% cash.  In connection with this price range, the holder of rights to acquire Aslin Group common stock would be expected to exercise their options or warrants prior to the closing.

On May 19, 2014, the board of directors of Aslin Group held a special meeting to consider the proposed transaction with First Business.  Also attending, in person or telephonically, were representatives of Stinson Leonard Street LLP, counsel to Aslin Group, and Macquarie Capital, financial advisor to Aslin Group.  Prior to the meeting, the board of directors received copies of the Merger Agreement and the related agreements, including the Stockholder Voting Agreement to be entered into by certain stockholders of Aslin Group, the non-compete agreement to be entered into by the CEO of Aslin Group and the employment agreements that First Business entered into with the five officers of Alterra Bank.  During the meeting, Aslin Group management detailed their due diligence review of First Business.  A representative of Macquarie Capital gave a report on the financial terms of the proposed transaction, information regarding peer companies and comparable transactions, and a net present value analysis of Aslin Group and First Business.  A representative of Stinson Leonard Street discussed with the board of directors the legal standards applicable to the board’s decisions and actions with respect to First Business’ merger proposal.

Following these reports and discussions, and discussion and analysis among the members of the Aslin Group board of directors, including consideration of the factors described under “The Merger—Reasons for the Merger and Aslin Group Board Recommendation,” the board of directors of Aslin Group determined that the merger, the Merger Agreement, and the transactions contemplated by the agreement were advisable for, fair to and in the best interests of Aslin Group and its stockholders, and the directors voted unanimously to adopt the Merger Agreement.

Macquarie Capital provided financial advisory services to Aslin Group during the first and second quarters of 2014, but a contract with Aslin Group was not finalized and signed until May 21, 2014.  The contract provided for a fixed transaction fee payable upon closing of the merger with First Business.  It also provided for a separate fairness opinion fee, if Aslin Group requested such an opinion.  The board of directors of Aslin Group did not request a fairness opinion from Macquarie Capital because the board was satisfied that the process leading up to the approval

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of the merger gave the directors adequate information to reach an informed business judgment regarding the merits of the merger and did not believe it was necessary to incur the cost of a fairness opinion.

On May 20, 2014, First Business’ board of directors met to consider the proposed transaction with Aslin Group.  Attending the meeting were representatives of First Business’ management, First Business’ legal counsel, Godfrey & Kahn, SC, and KBW, First Business’ financial advisor.  First Business’ management provided information regarding operational and financial considerations relating to the proposed consolidation of the businesses of First Business and Aslin Group, and provided a review of the overall due diligence process and results including the asset quality review of Alterra Bank’s loans and loan policies based on First Business’ due diligence review as well as a review conducted by an outside loan review firm.

Godfrey & Kahn reviewed the fiduciary duties and responsibilities of the board of directors in considering the proposed transaction, provided the board of directors with an overview of the legal due diligence conducted by it, and summarized the Merger Agreement and related agreements.  KBW reviewed certain financial aspects of the proposed transaction.

Following these presentations, reviews and a discussion among First Business’ board of directors, including consideration of the factors described under “The Merger—Reasons for the Merger and Aslin Group Board Recommendation,” First Business’ board of directors determined that it is in the best interest of First Business and its shareholders to proceed with the merger, and unanimously approved the Merger Agreement, and the transactions contemplated by the agreement.

On May 22, 2014, the Merger Agreement and related agreements were executed and delivered, and the transaction was announced on the morning of May 23, 2014, in a press release issued jointly by First Business and Aslin Group.

First Business’ Reasons for the Merger

In reaching its decision to approve the Merger Agreement, the board of directors considered a variety of factors, including the following:

·                  The merger will allow First Business to diversify its revenues and expand its presence in the thriving and complementary Kansas City metropolitan market which mirrors First Business’ established Midwestern markets in many ways demographically and economically and where First Business already operates its national equipment finance business;

·                  First Business’ belief that the merger will provide synergistic opportunities for First Business to expand Alterra Bank’s product and service offerings to include equipment finance, trust and investment services, factoring and asset based lending and that First Business will serve as a source of capital to fund Alterra Bank’s future growth;

·                  First Business’ belief that Alterra Bank, as the number one most active U.S. Small Business Administration lender in the Kansas City SBA district, will provide First Business with immediate access to talent, expertise and platforms in a commercial lending niche that it currently does not specialize in and which will be highly complementary to First Business’ current focus;

·                  First Business’ familiarity with and review of Aslin Group’s and Alterra Bank’s business, operations, management, markets, competitors, financial condition, earnings and prospects;

·                  Aslin Group’s and Alterra Bank’s solid track record of growth and profitability, stable credit quality and concentration in an attractive metropolitan area.  Since recapitalizing Alterra Bank in 2010, Aslin Group and Alterra Bank management significantly reduced legacy problem assets, restored profitability and significantly grew Alterra Bank’s loan portfolio.

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·                  Alterra Bank’s competitive position, talented team, focus on commercial clients, complementary limited branch business model, deep local experience, entrepreneurial approach and impressive track record of growth;

·                  First Business’ belief that, after the merger, the combined company will be able to continue to generate strong revenue growth rates, while benefitting from limited but achievable costs savings;

·                  The complementary aspects of First Business’ and Alterra Bank’s businesses, including a disciplined focus on asset quality, entrepreneurial approach to business banking, a well-defined niche client profile and compatibility of the companies’ cultures, management and operating styles;

·                  Similarities in First Business’ and Alterra Bank’s respective loan portfolio and funding mixes and market demographics;

·                  The commitment by certain key executives including Alterra Bank’s President and CEO and key Alterra Bank client contract team members to continue their employment after consummation of the merger; and

·                  First Business’ belief that the merger would be completed in a timely manner and that the management team of the combined company would be able to successfully integrate and operate the businesses of the combined company after the merger.

The foregoing discussion of the information and factors considered by First Business is not intended to be exhaustive, but includes the material factors considered by First Business’ board of directors. In reaching its determination to enter into the Merger Agreement, First Business did not assign any relative or specific weights to the foregoing factors.  First Business’ board of directors considered all these factors as a whole, including discussions with, and questioning of, First Business’ management and First Business’ financial and legal advisors, and overall considered the factors to be favorable to, and in support of, its determination.

Aslin Group Reasons for the Merger and Aslin Group Board Recommendation

In reaching the decision to approve a merger with First Business, the board of directors of Aslin Group considered a range of factors including, but not limited to, the following:

·                  Aslin Group’s belief that Alterra Bank’s historical and projected future growth would exceed the bank’s ability to generate and retain capital through earnings, and that Aslin Group would need to raise new capital in 2014, and additional capital in future years, to sustain the current and projected growth of Alterra Bank;

·                  Aslin Group’s expectation that the operating environment for Alterra Bank and community banks in general, and the current regulatory environment, will result in increased costs of operations, as well as increasing capital requirements and regulatory risk, thus reducing returns available to Aslin Group’s current stockholders and hindering Aslin Group’s ability to attract new capital on terms that would be attractive to the company and its current stockholders;

·                  After considering the cost of new capital to support growth of Alterra Bank, the board concluded that it was in the interest of Aslin Group’s stockholders to consider selling the company if a favorable transaction could be obtained;

·                  Aslin Group’s belief that the merger with First Business would provide Alterra Bank and its employees and customers with additional resources to meet the needs of entrepreneur-led companies and individuals in the greater Kansas City market, and additional capital for growth and expansion of Alterra Bank’s franchise;

·                  The culture and management practices of First Business appear to be compatible with those of Alterra Bank, thus enhancing the likelihood of closing;

·                  Based on the Aslin Group board of directors’ consideration of indications of interest from at least three other parties, as well as review of market data and trends in Midwestern bank mergers over the past year

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and consultations with Aslin Group’s financial advisor, the board of directors concluded that the price and terms offered by First Business were advisable for, fair to and in the best interest of Aslin Group and its stockholders;

·                  Aslin Group’s belief that the merger with First Business would result in significant synergies that would benefit customers and employees of Alterra Bank and the stockholders of Aslin Group;

·                  Based upon its review of the operating performance, credit quality and other due diligence related to First Business, Aslin Group’s board believed that the combined company would be able to provide the needed support for ongoing growth and expansion of Alterra Bank, including continuation of Alterra Bank’s niche business banking strategy;

·                  Aslin Group’s belief, for reasons including those listed above, that the merger would be well-received by employees and customers, and could be completed in a timely manner, thereby limiting risk of loss of key employees during the period that the merger is pending;

·                  Aslin Group stockholders would receive the stock of First Business in a tax-free exchange and would be able to participate in the future earnings and stock price appreciation of First Business after the merger;

·                  Aslin Group stockholders would have liquidity for their investment after the merger; and

·                  The board’s conclusion that the merger was fair to Aslin Group’s stockholders.

The foregoing information and description of factors considered by Aslin Group is not intended to be exhaustive, but includes the material factors considered and discussed by Aslin Group’s board of directors.  In reaching its determination to enter into the merger agreement, Aslin Group’s board of director did not assign any relative or specific weights to the foregoing factors.  Aslin Group’s board of directors considered all these factors as a whole, including discussions with, and questioning of, management of Aslin Group and Alterra Bank, and Aslin Group’s financial and legal advisors, and overall considered the factors to be favorable to, and in support of, its conclusion and recommendation.

Aslin Group’s board of directors determined that the merger, the Merger Agreement and the transactions contemplated thereby are advisable and in the best interests of Aslin Group and its stockholders.  Accordingly, the board of directors unanimously approved the Merger Agreement and unanimously recommends that Aslin Group’s stockholders vote “FOR” approval of the Merger Agreement and the transactions contemplated thereby.

Management and Board of Directors of First Business after the Merger

Upon completion of the merger, the board of directors of First Business will consist of the directors serving on the board of directors of First Business prior to the effective time of the merger.

Pamela Berneking will be President and Chief Executive Officer of Alterra Bank after the merger.  The remaining current directors and senior officers of First Business are expected to continue in their current positions, other than as has been or may be publicly announced by First Business in the normal course.  Information about the current First Business directors and executive officers can be found in the documents listed under “Incorporation of Certain Documents by Reference” included elsewhere in this proxy statement/prospectus.

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Interests of Aslin Group Directors and Executive Officers in the Merger

In considering the recommendations of the board of directors of Aslin Group, Aslin Group stockholders should be aware that certain directors and executive officers of Aslin Group and Alterra Bank have interests in the merger that may differ from, or may be in addition to, the interests of Aslin Group stockholders including, but not limited to potential payments under their employment agreements.  These interests are described in more detail and quantified below.  The board of directors of Aslin Group was aware of these interests and considered them, among other matters, when it adopted the Merger Agreement and in making its recommendations that the Aslin Group stockholders approve the Merger Proposal.

In connection with the merger, First Business has entered into employment-related agreements with various employees of Alterra Bank, including Pamela Berneking, President and Chief Executive Officer of Alterra Bank.  Descriptions of such agreements are as follows:

Offer Letters.  Kent Brown, Chief Lending Officer of Alterra Bank, Timothy Gervy, Chief Credit Officer of Alterra Bank, and Jason Moxness, Chief Banking Officer of Alterra Bank, have all executed offer letters with First Business (each an “Offer Letter”, together the “Offer Letters”).  Upon completion of the merger and pursuant to each Offer Letter, Messrs. Brown, Gervy and Moxness will continue to perform their current job responsibilities at their current salaries, which are $172,000, $172,000 and $150,000 per annum, respectively.  Messrs. Brown, Gervy and Moxness will also be entitled to participate during their employment in all Alterra Bank employee benefit plans, programs, practices or arrangements in which other Alterra Bank employees are eligible to participate.  Subject to certain vesting conditions in the Offer Letters, Messrs. Brown, Gervy and Moxness will be awarded a number of shares of restricted stock of First Business under the First Business 2012 Equity Incentive Plan (the “Equity Plan”).  Per the Offer Letters, the number of shares Messrs. Brown, Gervy and Moxness will receive will be determined as follows: $50,000, $25,000 and $45,000, respectively, all divided by the average closing price of First Business stock for the 10 trading days beginning five trading days before the effective time of the merger.

Doug Hoelscher, Chief Financial Officer of Alterra Bank, has also executed an agreement with First Business, where he will continue to serve as CFO of Alterra Bank for the six months after the effective time of the merger (the “Employment Period”) at his current salary.  Should Mr. Hoelscher remain employed for the entire six months of the Employment Period, he will receive a lump sum severance payment of six months base salary, which is $77,500, plus six months of his targeted incentive bonus payment, which is $19,375.

Berneking Employment Agreement.  Upon completion of the merger, Pamela Berneking will continue as President and CEO of Alterra Bank.  First Business has executed an employment agreement with Ms. Berneking (the “Berneking Employment Agreement”).  Under the Berneking Employment Agreement, Ms. Berneking will be paid a base salary of $200,000 per annum, which will be reviewed at least annually and may be increased from time to time subject to approval by the board of directors of First Business and its compensation committee.  For the calendar year of 2014, Ms. Berneking shall continue to participate in Alterra Bank’s annual incentive plan.  Starting the calendar year of 2015, Ms. Berneking will participate in the annual incentive bonus program approved by First Business’ compensation committee with performance metrics tailored to Alterra Bank, where her threshold bonus will be 10% of her base salary, her target bonus will be 30% of her base salary and her maximum bonus will be 60% of her base salary.  Under the Berneking Employment Agreement, Ms. Berneking will also be entitled to participate during her employment term in all Alterra Bank employee benefit plans, programs, practices or arrangements in which other Alterra Bank senior executives are eligible to participate from time to time.

Ms. Berneking is also entitled to participate during her employment term in all long-term incentive plans, including the Equity Plan.  Ms. Berneking will also be awarded a number of shares of restricted stock of First Business under the Equity Plan, determined as follows: $200,000 divided by the average closing price of First Business stock for the 10 trading days beginning five trading days before the effective time of the merger.  Such shares will cliff vest on the third anniversary of the merger if Ms. Berneking is still employed at that time.

Under the Berneking Employment Agreement, Ms. Berneking agreed that while she was employed by First Business or any of its affiliates and for a period of 18 months immediately following the termination of her employment for any reason, she would not either individually or on behalf of or through any third party, directly or indirectly: (1) solicit financial services business from, or conduct financial services business with, any client of First Business or its affiliates with which she had any contact during the period of one year prior to her cessation of

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employment or about whom she has “confidential information” (as that term is defined in the Berneking Employment Agreement); or (2) solicit, entice, persuade or encourage, or attempt to solicit, entice, persuade or encourage, any employee or consultant of First Business or any of its affiliates to terminate his or her employment with such entity.

Berneking Change in Control Agreement.  The Berneking Employment Agreement anticipates that First Business and Ms. Berneking will enter into an Executive Change-in-Control Severance Agreement (the “Berneking CIC Agreement”) contemporaneously with entering into the Berneking Employment Agreement.  First Business and Ms. Berneking entered into the Berneking CIC Agreement on July 7, 2014, effective as of the date of the Berneking Employment Agreement.  If the merger does not occur, the Berneking CIC Agreement will be null, void and of no further effect.

The material terms of the Berneking CIC Agreement are substantially similar to the material terms of the Executive Change-in-Control Severance Agreements between First Business and certain senior executives of First Business, other than the agreement with its Chief Executive Officer, which varies from the others.

The Berneking CIC Agreement provides that if a change in control of First Business, as defined in the Berneking CIC Agreement, occurs, and within 12 calendar months immediately thereafter, Ms. Berneking’s employment is terminated in a “qualifying termination”, she is entitled to severance benefits.  A “qualifying termination” means an involuntary termination of Ms. Berneking’s employment after the change in control without cause (or within six months prior to the change in control, if such involuntary termination is at the request of any party involved in the change in control transaction) or a voluntary termination after the change in control by Ms. Berneking for good reason.  Cause and good reason are both defined in the Berneking CIC Agreement.

The material components of the severance benefits are as follows:

·                  A cash amount equal to two times the greater of (a) Ms. Berneking’s then current base salary or (b) her base salary at the time of the change in control, payable in four equal semiannual installments, with the initial payment to occur on the first pay period following the six-month anniversary of the termination of employment, and the remaining payments to occur on each six-month anniversary thereafter until paid in full.

·                  A cash amount equal to the greater of (a) Ms. Berneking’s then-current target bonus opportunity or (b) her target bonus opportunity in effect at the time of change in control, prorated for the number of days she was employed during that year.  Payment of the prorated bonus is made in four quarterly installments at the same times as the multiple of base salary set forth above.

·                  For so long as Ms. Berneking is not eligible for group health insurance coverage from a subsequent employer, she is entitled to up to 18 months of group health insurance coverage, with her cost being equal to cost she paid as an employee, if allowable under the group health insurance plan currently in effect and anti-discrimination requirement applicable to health insurance.

The Berneking CIC Agreement also contains provisions for the non-solicitation of clients and protections of confidential information while Ms. Berneking is employed and for 24 months thereafter, and the non-solicitation of employees for 12 months after the earlier of (a) termination of her employment or (b) notice by Ms. Berneking that she is terminating employment.

Acceleration of Options and Restricted Stock.  Certain directors and officers of Aslin Group have options that entitle them to purchase, in the aggregate, up to 45.5 shares of Aslin Group’s common stock. Any outstanding options that are not vested will become immediately vested in connection with the merger. Under the terms of the Merger Agreement, all such outstanding options already vested or vesting as a result of a change in control pursuant to any incentive compensation plan, including the Aslin Group 2010 Equity Incentive Plan, will be exercised as of the effective time of the merger, and the shares issuable upon exercise thereof will be exchanged for cash and shares of First Business common stock pursuant to the Merger Agreement.

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In addition, certain officers of Aslin Group hold restricted shares of Aslin Group common stock.  All of the 30.75 outstanding unvested shares of Aslin Group restricted stock will vest on the effective date of the merger, and will also be exchanged for cash and shares of First Business common stock pursuant to the Merger Agreement.

TERMS OF THE MERGER AGREEMENT

Effects of the Merger

As a result of the merger, Acquisition Sub, a wholly-owned subsidiary of First Business that was incorporated in connection with the merger, will merge with and into Aslin Group.  Following the first merger, Aslin Group will continue as the surviving corporation.  Immediately after the effective time of the first merger, Aslin Group shall be merged with and into First Business, with First Business continuing as the surviving corporation of the second merger.  The separate corporate existence of Aslin Group will cease as of the effective time of this second-step merger.

As a result of the first merger, there will no longer be any shares of Aslin Group common stock.  Aslin Group stockholders will receive cash and shares of First Business common stock as the merger consideration, and will only participate in the combined company’s future earnings and potential growth through their ownership of First Business common stock.  All of the other incidents of direct stock ownership in Aslin Group, such as the right to vote on certain corporate decisions, to elect directors and to receive dividends and distributions from Aslin Group, will be extinguished upon completion of the merger.

Effective Time of the Merger

The closing of the merger will occur at such time, date and location as may be mutually agreed by the parties, or on a date specified by either party upon five business days’ written notice after the last to occur of the following events: (a) receipt of all consents and approvals of governmental authorities legally required to consummate the mergers and the expiration of all statutory waiting periods; and (b) approval of the Merger Agreement and the merger by the stockholders of Aslin Group.  However, scheduling or commencing the closing will not constitute a waiver of the closing conditions in the Merger Agreement.  The merger will be completed legally at the date and time specified in the articles of merger to be filed by First Business with the Secretary of State of the State of Delaware.  As of the date of this proxy statement/prospectus, the parties expect that the merger will be effective in late 2014.  However, there can be no assurance as to when or if the merger will occur.

As described below, if the merger is not completed by March 31, 2015, the Merger Agreement may be terminated by either First Business or Aslin Group, unless the action or failure to act of the terminating party has been a principal cause of or resulted in the failure of the merger to occur on or before such date if such action or failure to act constitutes a breach of any provision of the Merger Agreement.

Covenants and Agreements

Conduct of Business Prior to the Completion of the Merger.  Aslin Group has agreed that, prior to the effective time of the merger, it will operate its business only in the usual, regular and ordinary course consistent with past practices.  Aslin Group has agreed to use commercially reasonable efforts to preserve intact its business organization and assets, maintain its rights and franchises, retain the services of its officers and key employees and maintain its relationships with customers prior to closing.

In addition to the general covenants above, Aslin Group has agreed that prior to the effective time of the merger, subject to specified exceptions, it will, and will require its subsidiaries to:

·                  use commercially reasonable efforts to maintain and keep the owned real property and the leased real property in as good repair and condition as of the date of the Merger Agreement, ordinary wear and tear excepted;

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·                  use commercially reasonable efforts to keep in full force and effect director and officer liability insurance comparable in amount and scope of coverage to that maintained by it as of the date of the Merger Agreement;

·                  perform in all material respects all obligations required to be performed by it under all material contracts relating to or affecting its assets, properties, and business;

·                  comply with and perform in all material respects all obligations and duties imposed upon it by all applicable laws;

·                  maintain the “well capitalized” status of Alterra Bank;

·                  deliver written Phase I environmental site assessments for each piece of real property owned by Aslin Group or Aslin Group’s subsidiaries (excluding single family residences with an appraised value of less than $100,000) held by Aslin Group or any Aslin Group subsidiary as of the effective time;

·                  not take any action or fail to take any action which, individually or in the aggregate, can be expected to have an Aslin Group material adverse effect;

·                  use its reasonable best efforts to deliver all written consents prior to the effective time necessary to properly assign or transfer all material contracts to First Business;  and

·                  take any and all actions necessary to require that all stock options, restricted shares, or other awards already vested or vesting as a result of a change in control pursuant to any incentive compensation plan, either be exercised by the effective time or expire.

Additionally, Aslin Group has agreed that prior to the effective time of the merger, subject to specified exceptions, it will not, and will not permit its subsidiaries to, without the prior approval of First Business:

·                  adopt, amend, renew or terminate any employment contract or employment arrangement or any other agreement, arrangement, plan or policy between Aslin Group or any Aslin Group subsidiary and one or more of its current or former directors, officers or employees, or increase in any manner the compensation or benefits of any director, officer or employee, except for normal increases for non-executive employees in the ordinary course of business consistent with past practices;

·                  declare or pay any dividend on, or make any other distribution in respect of, its outstanding shares of capital stock, except for dividends by an Aslin Group subsidiary to Aslin Group;

·                  except as contemplated by the Merger Agreement, merge with or into any other entity, permit any other entity to merge into it or consolidate with any other entity, or effect any reorganization or recapitalization;

·                  acquire the assets or any equity interests of any entity or person other than in the ordinary course of business;

·                  liquidate, sell, dispose of, encumber, or permit any liens with respect to any assets or acquire any assets, including the extension of any credit, with a value in excess of $100,000 outside of the ordinary course of business; provided, however, that Aslin Group or an Aslin Group subsidiary may extend credit in excess of $100,000 for transactions which are outside of the ordinary course of business after providing First Business with such credit documents as First Business, in its reasonable discretion, deems necessary, and provided further that First Business does not disapprove of the credit extension in writing within three business days after receiving such credit documents;

·                  with respect to Aslin Group and ASA Holdings, LLC, borrow money from any entity or person;

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·                  with respect to Alterra Bank, borrow money from any entity or person other than from the Federal Home Loan Bank of Topeka in the ordinary course of business; provided, however, this will not affect the ability of Aslin Group or Alterra Bank to accept deposits;

·                  acquire, issue, sell or deliver, split, reclassify, combine or otherwise adjust any securities issued by Aslin Group or any of Aslin Group’s subsidiaries, or grant or issue any options, warrants or other rights for issue thereof;

·                  propose or adopt any amendments to Aslin Group certificate of incorporation or bylaws, or any similar organizational documents of Aslin Group’s subsidiaries;

·                  change any of its methods of accounting in effect at December 31, 2013 or change any of its methods of reporting income or deductions for federal income tax purposes from those employed in the preparation of the federal income tax returns for the taxable year ending December 31, 2013, except as may be required by GAAP;

·                  change any lending, investment, liability management or other material policies concerning the business or operations of Aslin Group or any of Aslin Group’s subsidiaries, except as required by law or by a governmental authority:

·                  take any of the following actions:

·                  acquire or sell any contracts for the purchase or sale of financial or other futures or any put or call options, or enter into any hedges or interest rate swaps relating to cash, securities, or any commodities whatsoever or enter into any other derivative transaction, which would have gains or losses in excess of $20,000, or enter into, terminate or exchange a derivative instrument with a notional amount in excess of $20,000 or having a term of more than five years;

·                  make any investment with a maturity of five years or more;

·                  incur any material liabilities or material obligations, whether directly or by way of guaranty, including any obligation for borrowed money in excess of an aggregate of $50,000 (for Aslin Group and Aslin Group’s subsidiaries on a consolidated basis) except in the ordinary course of business consistent with past practice;

·                  enter into any contract with respect to any discharge, waiver, satisfaction, release or relinquishment of any material contract rights, liens, debts or claims, not in the ordinary course of business and consistent with past practices (such as the creation of deposit liabilities, purchases of federal funds, advances from the Federal Reserve Bank or Federal Home Loan Bank, and entry into repurchase agreements fully secured by United States government or agency securities, which are in the ordinary course of business and consistent with past practices), or impose, or suffer the imposition of, on any material asset of Aslin Group or any of Aslin Group’s subsidiaries of any lien or permit any such lien to exist (other than in connection with deposits, repurchase agreements, bankers acceptances, “treasury tax and loan” accounts established in the ordinary course of business, the satisfaction of legal requirements in the exercise of trust powers, and liens in effect as of the date of the Merger Agreement) and in no event with a value in excess of $20,000 individually;

·                  settle any proceeding for any amount in excess of $20,000 or in any manner which would restrict in any material respect the operations or business of Aslin Group or any of Aslin Group’s subsidiaries;

·                  purchase any new financial product or instrument outside of the ordinary course of business which involves entering into a contract under which the aggregate obligations of Aslin Group would exceed $20,000 or which would have a term of six months or longer;

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·                  make any capital expenditure, except in the ordinary course and consistent with past practice and in no event in excess of $20,000 individually;

·                  take any action or fail to take any action which, individually or in the aggregate, would be reasonably expected to have an Aslin Group material adverse effect;

·                  take any action that would adversely affect or delay the ability of Aslin Group to perform any of its obligations on a timely basis under the Merger Agreement or cause any of the conditions set forth in Article VII (Conditions of the Merger) of the Merger Agreement to not be satisfied;

·                  fail to maintain in their present form and with their present coverage all existing policies of insurance with respect to any owned real property and leased real property;

·                  fail to comply with any law or order applicable to owned real property and leased real property if such failure would materially adversely affect the condition (physical or otherwise) of such property or Aslin Group’s ability to operate its business therefrom; or

·                  agree in writing or otherwise to do any of the foregoing.

First Business has agreed that prior to the effective time of the merger, subject to specified exceptions, it will, and will cause its subsidiaries to:

·                  maintain its corporate existence in good standing and maintain all books and records in accordance with accounting principles and practices as used in First Business’ financial statements applied on a consistent basis;

·                  maintain the “well capitalized” status of each bank subsidiary;

·                  conduct its business in a manner that does not violate any law, except for possible violations which, individually or in the aggregate, do not have, and would not reasonably be expected to have, a material adverse effect;

·                  operate its business in the usual, regular and ordinary course consistent with past practices;

·                  use its reasonable best efforts to deliver any necessary consents or waivers from BMO Harris Bank, N.A. pursuant to its Business Loan Agreement prior to Aslin Group’s stockholder meeting; and

·                  not take any action or fail to take any action which, individually or in the aggregate, can be expected to have a First Business material adverse effect.

Further, First Business has agreed that prior to the effective time of the merger, subject to specified exceptions, it will not, and will cause its subsidiaries to not, take any action that would adversely affect or delay the ability of First Business to perform any of its obligations on a timely basis under the Merger Agreement or cause any of the conditions set forth in Article VII (Conditions of the Merger) of the Merger Agreement to not be satisfied, and will not amend its articles of incorporation or bylaws in a manner that would materially and adversely affect the economic benefits of the merger to the holders of Aslin Group common stock.

Regulatory Matters.  First Business and Aslin Group have agreed to promptly prepare and file with the SEC a registration statement on Form S-4, of which this proxy statement/prospectus is a part.  First Business and Aslin Group have agreed to use all reasonable efforts to have the Form S-4 declared effective under the Securities Act as promptly as practicable after such filing, and to mail or deliver the proxy statement/prospectus to their stockholders.  First Business and Aslin Group have each agreed to furnish all information concerning itself and its affiliates that is required to be included in this proxy statement/prospectus or, to the extent applicable, the other filings, or that is customarily included in a proxy statement/prospectus or other filings prepared in connection with transactions of the type contemplated by the Merger Agreement.

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First Business and Aslin Group have agreed to use their respective reasonable best efforts to obtain all consents and orders required under law (including, without limitation, all rulings and approvals of governmental authorities) and from parties to material contracts required in connection with the authorization, execution and delivery of the Merger Agreement and the consummation by them of the merger, and make all necessary filings, and thereafter make any other required submissions, with respect to the Merger Agreement and the merger required under applicable federal and state securities laws, the Bank Holding Company Act, the Federal Deposit Insurance Act, any state banking laws and any other applicable federal or state banking laws and any other applicable law.  First Business and Aslin Group will cooperate with each other in connection with the making of all such filings, including providing copies of all such documents to the non-filing party and its advisors prior to filing and, if requested, to accept all reasonable additions, deletions or changes suggested in connection therewith.  Aslin Group and First Business will furnish all information required for any application or other filing to be made pursuant to the rules and regulations of any applicable law in connection with the transactions contemplated by the Merger Agreement.  In case at any time after the effective time any further action is necessary or desirable to carry out the purposes of the Merger Agreement, the officers and directors of First Business and Aslin Group have agreed to use commercially reasonable efforts to take all such necessary action.

No Solicitation; Board Recommendation.  Before the effective time of the Merger Agreement, Aslin Group has agreed that neither it nor any subsidiary shall, and each shall use its best efforts to cause their respective representatives not to, initiate, solicit or take any action to facilitate or encourage, directly or indirectly, any inquiries or the making or submission of any proposal or offer (including, without limitation, any proposal or offer to its stockholders) with respect to any acquisition transaction, or, except as provided below, engage in any negotiations concerning, or provide any confidential information or data to, or have any discussions with, any entity, person or group relating to an alternative acquisition proposal.  Aslin Group has also agreed to immediately cease and cause to be terminated any existing activities, discussions or negotiations with any parties conducted on or prior to the date of the Merger Agreement with respect to any of the foregoing, and it will inform such parties of its obligations under the Merger Agreement; and that it will immediately notify First Business if any such inquiries, proposals or offers are received by, any such information is requested from, or any such negotiations or discussions are sought to be initiated or continued with, it or any of such entities, persons or groups.

Aslin Group’s board of directors has resolved to recommend that Aslin Group’s stockholders vote in favor of and adopt and approve the Merger Agreement at the Aslin Group stockholders’ meeting.  Neither Aslin Group’s board of directors nor any committee thereof shall withhold, withdraw, amend or modify, or propose or resolve to withhold, withdraw, amend or modify Aslin Group’s board of directors’ recommendation in a manner adverse to First Business.

However, prior to the receipt of the requisite stockholder approval at the Aslin Group stockholders’ meeting, solely in response to an unsolicited bona fide written acquisition proposal that did not result from the breach of the Merger Agreement and following delivery to First Business of notice of such acquisition proposal, Aslin Group is permitted to furnish information to the party making the acquisition proposal and/or engage in discussions or negotiations regarding the acquisition proposal, but only if (A) Aslin Group’s board of directors has reasonably concluded in good faith that the person or group making such acquisition proposal will have adequate sources of financing to consummate such acquisition proposal, (B) prior to furnishing any information to such person, such person shall have entered into a confidentiality agreement with Aslin Group (which shall expressly permit Aslin Group to disclose the terms of the confidentiality agreement to First Business) on terms no less favorable to Aslin Group than the Confidentiality Agreement between First Business and Aslin Group, (C) Aslin Group’s board of directors reasonably determines in good faith that the acquisition proposal would reasonably be expected to result in a “superior offer” (a defined below), and (D) Aslin Group’s board of directors based on the written opinion of outside legal counsel, reasonably determines in good faith that such action is required for Aslin Group’s board of directors to comply with its fiduciary duties to stockholders imposed by law.

A “superior offer” means an offer related to a merger or acquisition transaction on terms that Aslin Group’s board of directors determines, in its good faith judgment (after receipt and consideration of the written opinion of a financial advisor of nationally recognized reputation to the effect that the consideration offered in such offer is superior, from a financial point of view, to the per share consideration to be received in the merger), to be (1) more favorable to Aslin Group stockholders than the terms of the merger, and (2) reasonably likely to be consummated in accordance with its terms, taking into account all financial, regulatory, legal and other aspects of the proposal, including, to the extent debt financing is required, whether such proposal is fully financed by means of an executed

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customary commitment letter from a reputable person that has agreed to provide or cause to be provided the amounts set forth therein, after taking into account any revisions to the terms of the Merger Agreement and the merger proposed by First Business during the notice period set forth in the Merger Agreement.

NASDAQ Listing.  First Business will use its reasonable efforts to cause the shares of First Business common stock to be issued in the merger to be approved for listing on The NASDAQ Global Select Market, subject to official notice of issuance, prior to the effective time of the merger.

Update Disclosure.  Until the effective time, Aslin Group has agreed to update the information contained in the disclosure schedule to the Merger Agreement, to reflect any matters which have occurred from and after the date of the Merger Agreement which, if existing on the date of the Merger Agreement, would have been required to be described therein.

Notice of Breach.  Each party has agreed to notify the other party in the event it becomes aware of the impending or threatened occurrence of any event or condition which would cause or constitute a material breach of any of its representations or agreements contained or referred to herein, and use its reasonable best efforts to prevent or promptly remedy the same.

Tax Treatment.  Each party has agreed to use its reasonable best efforts to cause the merger to qualify as a reorganization under Section 368(a)(1)(A) of the Internal Revenue Code.

Delivery of Stockholder List.  Aslin Group has agreed to deliver to First Business, prior to the effective time, a list of the names and addresses of Aslin Group stockholders, their holdings of stock as of the latest practicable date, and such other information as First Business may reasonably request.

Loan and Investment Policies.  Aslin Group has agreed to maintain and to cause Aslin Group subsidiaries to maintain their existing loan and investment policies and procedures designed to ensure safe and sound banking practices, which shall remain in effect, except as otherwise agreed in writing by First Business, until the earlier of the effective time or termination of the Merger Agreement.  To the extent permitted by applicable law, First Business shall have the right to designate at least one observer to attend all meetings of Aslin Group’s (i) loan approval committee, or similar committee at any Aslin Group subsidiary designated by First Business, and (ii) investment committee or similar committee at any Aslin Group subsidiary designated by First Business, and Aslin Group will ensure that such representatives receive all information given by Aslin Group, Aslin Group subsidiary, or their respective agents to Aslin Group’s or Aslin Group subsidiaries’ committee members.

Access and Information.  Until the earlier of the effective time or the termination of the Merger Agreement, each party will give the other party and its representatives reasonable access to certain persons and information, including the officers, employees, properties, books and records of such company, as well as other information that is requested in connection with certain permitted activities, including due diligence review, verification of representations and warranties, confirming compliance with the Merger Agreement and preparing for the consummation of the transactions contemplated by the Merger Agreement.

Return of Documents.  In the event of termination of the Merger Agreement, each party has agreed to return to the other party all originals and copies of documents and work papers obtained by such party from the other party, and not to use, disclose or divulge any information so obtained, subject to certain exceptions.

Directors’ and Officers’ Indemnification and Insurance.  First Business has agreed to succeed to Aslin Group’s obligations with respect to indemnification or exculpation existing in favor of the directors, officers, employees and agents of Aslin Group and Aslin Group’s subsidiaries as provided in Aslin Group certificate of incorporation and bylaws, indemnification agreements or otherwise in effect as of the date of the Merger Agreement with respect to matters occurring before the effective time.  Aslin Group will not amend or enter into new indemnification arrangements or agreements from and after the date of the Merger Agreement.

Before Closing, Aslin Group will obtain a six year tail insurance coverage policy (on terms reasonably acceptable to First Business) at Aslin Group’s expense, relating to the policies of directors’ and officers’ liability insurance currently maintained by Aslin Group as of the date of the Merger Agreement with respect to claims arising from facts or events that occurred on or before the effective time.

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Employee Matters.  The Merger Agreement provides that First Business shall provide each employee who continues employment with Alterra Bank after the closing date a rate of salary that is not less than the continuing employee’s current rate of salary as of the date of the Merger Agreement for at least one year.  Until at least December 31, 2014, continuing employees of Alterra Bank shall continue to be eligible for Alterra Bank’s benefits and incentive programs in effect as of January 1, 2014.  However, nothing in the Merger Agreement requires First Business to continue to employ any particular employee. Notwithstanding the terms set forth in the Merger Agreement, in the event any employee who continues employment with Alterra Bank after the closing of the Merger Agreement has entered into a written employment agreement or arrangement with First Business or Alterra Bank, the terms of such written employment agreement or arrangement will govern.

Representations and Warranties

The Merger Agreement contains representations and warranties made by Aslin Group to First Business relating to a number of matters, including the following:

·                  corporate organization and qualification;

·                  subsidiaries;

·                  articles of incorporation and bylaws;

·                  capitalization of Aslin Group and its subsidiaries;

·                  authority to execute the Merger Agreement and perform its obligations thereunder;

·                  no conflict with organizational documents, laws and contracts;

·                  required filings and consents;

·                  regulatory approvals;

·                  compliance with laws and material contracts;

·                  securities and banking reports and financial statements;

·                  absence of certain changes or events since December 31, 2013;

·                  absence of proceedings and orders;

·                  employee benefit plans;

·                  information in this registration statement and proxy statement/prospectus;

·                  owned property and leased property;

·                  environmental matters;

·                  absence of agreements restricting the business of Aslin Group;

·                  taxes and tax matters;

·                  insurance;

·                  brokers;

·                  absence of a material adverse effect;

·                  material contracts;

·                  vote required;

·                  stockholders’ agreement termination;

·                  absence of related party loans;

·                  allowances for loan and lease losses;

·                  administration of trust accounts;

·                  loans and investment securities; and

·                  due inquiry of Aslin Group’s representatives to inform themselves as to the accuracy of certain of the foregoing.

Certain of these representations and warranties are qualified as to “materiality” or “material adverse effect”.  For purposes of the Merger Agreement, an Aslin Group “material adverse effect” means an effect, that, individually or in the aggregate with other effects, (i) is material and adverse to the business, assets, liabilities, results of operations or financial condition of Aslin Group and Aslin Group’s subsidiaries taken as a whole, or (ii) materially impairs the ability of Aslin Group to consummate the transactions contemplated by the Merger Agreement; provided, however, that the term Aslin Group material adverse effect is not deemed to include the impact of (a) any effect to the extent resulting from the announcement of the Merger Agreement or the transactions contemplated thereby; (b) any effect resulting from compliance with the covenants, terms and conditions of the Merger Agreement; (c) any effect to the extent resulting from changes in laws or interpretations thereof generally applicable to the banking industry; (d) any effect to the extent resulting from changes in generally accepted accounting principles which Aslin Group is required to adopt; (e) changes attributable to or resulting from changes in general

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economic conditions affecting the banking industry generally, including, without limitation, changes in interest rates (unless such effect would reasonably be expected to have a materially disproportionate impact on the business, assets, liabilities, results of operations or financial condition of Aslin Group relative to other banking industry participants); or (f) actions contemplated and permitted by the Merger Agreement.

The representations and warranties in the Merger Agreement do not survive the effective time of the merger and, as described below under “Effect of Termination,” if the Merger Agreement is validly terminated, there will be no liability under the representations and warranties of the parties, unless a party knowingly breached the Merger Agreement.

Conditions to the Merger

Conditions to Each Party’s Obligations.  The respective obligations of each of First Business and Aslin Group to complete the merger are subject to the satisfaction of the following conditions:

·                  effectiveness of the Registration Statement on Form S-4;

·                  the approval of the Merger Agreement and the merger by the Requisite Vote of the stockholders of Aslin Group;

·                  the receipt of all necessary approvals or exemptions relating to the mergers from the appropriate governmental authorities, including the Board of Governors of the Federal Reserve System and the Office of the State Bank Commissioner of Kansas;

·                  the absence of any law or order preventing or prohibiting consummation of the transactions contemplated by the Merger Agreement or restricting the consummation of the transactions contemplated by the Merger Agreement in a manner that would have a material adverse effect;

·                  the absence of any action taken, or any statute, rule, regulation or order enacted, entered, enforced or deemed applicable to the mergers, by any governmental authority which imposes any condition or restriction upon First Business or Aslin Group or their respective subsidiaries, which would materially adversely impact the economic or business benefits of the transactions contemplated by the Merger Agreement in such a manner as to render inadvisable the consummation of the mergers; and

·                  the filing of a notification form (and no objection thereto) for the listing of the First Business common stock to be issued at the effective time on NASDAQ.

Conditions to Obligations of First Business.  The obligation of First Business and Acquisition Sub to complete the merger is also subject to the satisfaction, or waiver by First Business, of the following conditions:

·                  the accuracy of the representations and warranties of Aslin Group as of the closing date of the merger, other than, in most cases, those failures to be true and correct that (disregarding any materiality, material adverse effect and similar qualifying terms), individually or in the aggregate, would not reasonably be expected to result in a material adverse effect on Aslin Group;

·                  the receipt by First Business of an officer’s certificate regarding the accuracy of the representations and warranties of Aslin Group;

·                  the performance or compliance by Aslin Group in all material respects with all agreements and covenants required by the Merger Agreement to be performed or complied with by it on or prior to the effective time;

·                  the receipt of all approvals, consents and orders required to be obtained under the Merger Agreement, and the completion of all filings and notifications required to be made by Aslin Group for the authorization, execution and delivery of the Merger Agreement, and the consummation by Aslin Group

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of the transactions contemplated by the Merger Agreement, except where the failure to obtain any such consents or orders, or make any such filings or notifications, would not have a material adverse effect;

·                  the absence of any pending proceeding before any governmental authority or any other person challenging or seeking material damages in connection with the mergers, or seeking to restrain, prohibit or limit the exercise of full rights of ownership or operation by First Business or the First Business subsidiaries of all or any portion of the business or assets of Aslin Group, which is reasonably likely to have a material adverse effect;

·                  the absence of an Aslin Group material adverse effect and an officer’s certificate to that effect;

·                  holders of five percent or fewer of all outstanding shares of Aslin Group’s common stock shall have undertaken steps to perfect appraisal rights in accordance with Section 262 of the DGCL;

·                  the execution of a non-competition agreement with Malcolm M. Aslin; employment-related agreements with certain executive officers of Aslin Group and Alterra Bank, including Pamela Berneking, Kent Brown, Doug Hoelscher, Jason Moxness, and Tim Gervy; and the voting agreement with certain Aslin Group stockholders;

·                  the exercise, before the effective time, of all Aslin Group warrants and options;

·                  the receipt of certain written Phase I environmental site assessments conducted in accordance with commercially reasonable standards; and

·                  the receipt of the required consent from BMO Harris Bank N.A. pursuant to the Business Loan Agreement.

Conditions to Obligations of Aslin Group.  The obligation of Aslin Group to complete the merger is also subject to the satisfaction, or waiver by Aslin Group, of the following conditions:

·                  the accuracy of the representations and warranties of First Business as of the closing date of the merger, other than, in most cases, those failures to be true and correct that (disregarding any materiality, material adverse effect and similar qualifying terms), individually or in the aggregate, would not reasonably be expected to result in a material adverse effect on First Business;

·                  the receipt by Aslin Group of an officer’s certificate regarding the accuracy of the representations and warranties of First Business;

·                  the performance or compliance by First Business in all material respects with all agreements and covenants required by the Merger Agreement to be performed or complied with by it on or prior to the effective time;

·                  the receipt of all approvals, consents and orders required to be obtained under the Merger Agreement, and the completion of all filings and notifications required to be made by First Business for the authorization, execution and delivery of the Merger Agreement, and the consummation by First Business of the transactions contemplated by the Merger Agreement, except where the failure to obtain any such consents or orders, or make any such filings or notifications, would not have a material adverse effect;

·                  the receipt of an opinion of Stinson Leonard Street LLP, in form and substance reasonably satisfactory to Aslin Group, dated as of the closing date, to the effect that the mergers will be treated for federal income tax purposes as a reorganization within the meaning of Section 368(a) of the Internal Revenue Code; and

·                  the absence of a First Business material adverse effect and receipt of an officer’s certificate to that effect.

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Termination; Termination Fee

The Merger Agreement can be terminated by either party at any time before completion of the merger in the following circumstances:

·                  by mutual written consent duly authorized by First Business’ board of directors and Aslin Group’s board of directors;

·                  if the merger has not been consummated by March 31, 2015, unless extended by First Business’ board of directors and Aslin Group’s board of directors for any reason; provided, however, that the right to terminate the Merger Agreement will not be available to any party whose action or failure to act has been a principal cause of or resulted in the failure of the merger to occur on or before such date if such action or failure to act constitutes a breach of any provision of the Merger Agreement;

·                  if a governmental authority has issued a non-appealable order or taken any other action having the effect of restraining, enjoining or otherwise prohibiting the mergers; or

·                  if the Requisite Vote is not obtained at the Aslin Group stockholders’ meeting or at any adjournment or postponement thereof; provided, however, that the right to terminate the Merger Agreement will not be available to Aslin Group where the failure to obtain approval by Aslin Group stockholders is caused by Aslin Group’s action or failure to act, and such action or failure to act is a breach of the Merger Agreement.

The Merger Agreement can be terminated by Aslin Group at any time before completion of the merger in the following circumstances:

·                  upon a breach by First Business of any covenant or agreement in the Merger Agreement, or if any representation or warranty of First Business was untrue when made or shall have become untrue, in either case such that the closing conditions of Aslin Group to effect the merger would not be satisfied as of the time of such breach or as of the time such representation or warranty shall have become untrue, provided, that if the inaccuracy or breach was unintentional and is curable by First Business, then Aslin Group may not terminate the Merger Agreement for ten days, so long as First Business continues to exercise commercially reasonable efforts to cure such breach;

·                  if any of the closing conditions to the obligations of Aslin Group to effect the merger have not been satisfied or waived by Aslin Group at closing or Aslin Group reasonably determines that the timely satisfaction of any closing condition has become impossible (other than as a result of any failure on the part of Aslin Group to comply with or perform any covenant or obligation of Aslin Group set forth in the Merger Agreement);

·                  if there has been a First Business material adverse effect between the date of the Merger Agreement and the effective time of the Merger Agreement; or

·                  if Aslin Group opts to enter into a definitive agreement with respect to a Superior Offer, after complying with its obligations related to the non-solicitation of alternative business combination transactions.

The Merger Agreement can be terminated by First Business at any time prior to completion of the merger in the following circumstances:

·                  upon a breach by Aslin Group of any covenant or agreement in the Merger Agreement, or if any representation or warranty of Aslin Group was untrue when made or shall have become untrue, in either case such that the closing conditions of First Business to effect the merger would not be satisfied as of the time of such breach or as of the time such representation or warranty shall have become untrue, provided, that if the inaccuracy or breach was unintentional and is curable by Aslin Group, then

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First Business may not terminate the Merger Agreement for ten days so long as Aslin Group continues to exercise commercially reasonable efforts to cure such breach;

·                  if there is a Change of Recommendation (as defined in the Merger Agreement) or if Aslin Group shall have materially violated or breached its obligations not to solicit proposals relating to alternative business combination transactions;

·                  if any of the closing conditions to the obligations of First Business to effect the merger have not been satisfied or waived by First Business at closing or First Business reasonably determines that the timely satisfaction of any closing condition has become impossible (other than as a result of any failure on the part of First Business to comply with or perform any covenant or obligation of First Business in the Merger Agreement); or

·                  if there has been an Aslin Group material adverse effect between the date of the Merger Agreement and the effective time of the Merger Agreement.

The Merger Agreement provides that, in the event of termination of the Merger Agreement (i) by First Business if there is a Change of Recommendation or if Aslin Group shall have materially violated or breached its obligations not to solicit proposals relating to alternative business combination transactions, (ii) by Aslin Group in order to enter into a definitive agreement with respect to an unsolicited Superior Offer (as defined in the Merger Agreement), or (iii) by either party if the Requisite Vote of Aslin Group’s stockholders is not obtained at the Aslin Group stockholders’ meeting and there has been a Change of Recommendation, then Aslin Group will pay a termination fee of $1.2 million to First Business within two business days after such termination.

Amendments and Waivers

The Merger Agreement may only be amended by an instrument in writing signed on behalf of each of the parties.  At any time prior to the effective time of the merger, any party may (a) extend the time for the performance of any of the obligations or other acts of the other parties hereto, (b) waive any inaccuracies by the other parties in the representations and warranties contained in the Merger Agreement or in any document delivered pursuant thereto, and (c) waive compliance by the other parties with any of the Merger Agreements or conditions contained therein.  Any agreement on the part of a party to any extension or waiver must be in writing signed on behalf of such party.  Any such extension or waiver or failure to insist on strict compliance with an obligation, covenant, agreement or condition will not operate as a waiver of any subsequent or other failure.

Fees and Expenses

Except for any termination fees, as described elsewhere in this proxy statement/prospectus, all fees and expenses incurred in connection with the merger, the Merger Agreement, and the transactions contemplated by the Merger Agreement (including costs and expenses of printing and mailing this proxy statement/prospectus) will be paid by the party incurring such fees or expenses, whether or not the merger is completed.

This summary and the copy of the Merger Agreement attached to this proxy statement/prospectus as Appendix A are included solely to provide investors with information regarding the terms of the Merger Agreement.  They are not intended to provide factual information about the parties or any of their respective subsidiaries or affiliates.  The Merger Agreement contains representations and warranties by First Business and Aslin Group, which were made only for purposes of that agreement and as of specific dates.  The representations, warranties and covenants in the Merger Agreement were made solely for the benefit of the parties to the Merger Agreement, may be subject to limitations agreed upon by the contracting parties, including being qualified by confidential disclosures made for the purposes of allocating contractual risk between the parties to the Merger Agreement instead of establishing these matters as facts, and may be subject to standards of materiality applicable to the contracting parties that differ from those generally applicable to investors.  In reviewing the representations, warranties and covenants contained in the Merger Agreement or any descriptions thereof in this summary, it is important to bear in mind that such representations, warranties and covenants or any descriptions thereof were not intended by the parties to the Merger Agreement to be characterizations of the actual state of facts or condition of First Business, Aslin Group or any of their respective subsidiaries or affiliates.  Moreover, information concerning the subject matter of the representations, warranties and covenants may change after the date of the Merger Agreement, which subsequent

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information may or may not be fully reflected in First Business’ public disclosures.  For the foregoing reasons, the representations, warranties and covenants or any descriptions of those provisions should not be read alone and should instead be read in conjunction with the other information contained in the reports, statements and filings that First Business publicly files with the SEC.  For more information regarding these documents, see the section entitled “Where You Can Find More Information” included elsewhere in this proxy statement/prospectus.

MATERIAL UNITED STATES FEDERAL INCOME TAX CONSEQUENCES OF THE MERGERS

Subject to the assumptions and limitations discussed below and in the opinions of Godfrey & Kahn, S.C., counsel to First Business, and Stinson Leonard Street LLP, counsel to Aslin Group, the following discussion sets forth the material United States federal income tax consequences of the mergers to Aslin Group stockholders who are U.S. Holders (as defined below) of Aslin Group common stock.  This discussion is based on the Internal Revenue Code and the related tax regulations issued by the United States Internal Revenue Service, or “Treasury Regulations”, administrative interpretations and court decisions in effect as of the date of this proxy statement/prospectus, all of which are subject to change, possibly with retroactive effect.  Any change could affect the accuracy of the statements and the conclusions discussed below and the tax consequences of the mergers.  This discussion does not address all issues that may be applicable to holders who acquired shares of Aslin Group common stock pursuant to the exercise of options or otherwise as compensation.  Furthermore, this discussion does not address any alternative minimum tax or any state, local or foreign tax considerations.  We urge you to consult your own tax advisor as to the specific tax consequences of the mergers, including the applicable federal, state, local and foreign tax consequences to you of the mergers.

For purposes of this discussion, a U.S. holder is a beneficial owner of Aslin Group common stock who for United States federal income tax purposes is:

·                  a citizen or resident of the United States;

·                  a corporation, or an entity treated as a corporation, created or organized in or under the laws of the United States or any state or political subdivision thereof and taxed under Subchapter C of the Internal Revenue Code;

·                  a trust that (1) is subject to (A) the primary supervision of a court within the United States and (B) the authority of one or more United States persons to control all substantial decisions of the trust or (2) has a valid election in effect under applicable Treasury Regulations to be treated as a United States person; or

·                  an estate that is subject to United States federal income tax on its income regardless of its source.

If a corporation taxed under Subchapter S of the Internal Revenue Code, referred to as an “S corporation”, or a partnership (including for this purpose any entity treated as a partnership for United States federal income tax purposes) holds Aslin Group common stock, the tax treatment of a shareholder or partner generally will depend on the status of the shareholder or partner and the activities of the S corporation or partnership.  If you are a shareholder of an S corporation or partner of a partnership holding Aslin Group common stock, you should consult your tax advisor.

This discussion addresses only those Aslin Group stockholders that hold their Aslin Group common stock as a capital asset within the meaning of Section 1221 of the Internal Revenue Code, and does not address all the United States federal income tax consequences that may be relevant to particular Aslin Group stockholders in light of their individual circumstances or to Aslin Group stockholders that are subject to special rules, such as:

·                  financial institutions;

·                  pass-through entities or investors in pass-through entities;

·                  insurance companies;

·                  tax-exempt organizations;

·                  dealers in securities;

·                  traders in securities that elect to use a mark to market method of accounting;

·                  persons who exercise appraisal rights;

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·                  persons who hold Aslin Group common stock as part of a straddle, hedge, appreciated financial position, synthetic security, constructive sale, conversion transaction or other integrated investment or risk reduction transaction;

·                  certain expatriates or persons that have a functional currency other than the U.S. dollar;

·                  regulated investment companies;

·                  persons who are not U.S. holders; and

·                  stockholders who acquired their shares of Aslin Group common stock through the exercise of an employee stock option or otherwise as compensation or through a tax-qualified retirement plan.

In addition, the discussion does not address any alternative minimum tax nor does it address any state, local or foreign tax consequences of the mergers.

The following discussion is based on the Internal Revenue Code, its legislative history, existing and proposed regulations thereunder and published rulings and decisions, all as currently in effect as of the date hereof, and all of which are subject to change, possibly with retroactive effect.  Any such change could affect the continuing validity of this discussion.

First Business and Aslin Group have structured the mergers, taken together, to qualify as a reorganization within the meaning of Section 368(a) of the Internal Revenue Code.  The obligation of Aslin Group to complete the mergers is conditioned upon the receipt of an opinion from Stinson Leonard Street LLP, counsel to Aslin Group, to the effect that the mergers, taken together, will for federal income tax purposes qualify as a reorganization within the meaning of Section 368(a) of the Internal Revenue Code.  In addition, in connection with the filing of the registration statement of which this document is a part, Stinson Leonard Street LLP has delivered an opinion to Aslin Group to the same effect as the opinion described above.  This opinion will be based on the basis of facts, representations and assumptions set forth in such opinion that are consistent with the state of facts existing as of the closing date of the merger.  The accuracy of such assumptions, representations and warranties, and compliance with such covenants, could affect the conclusions set forth in such opinion.  This opinion is not binding on the Internal Revenue Service or the courts.  First Business and Aslin Group have not requested and do not intend to request any ruling from the Internal Revenue Service as to the United States federal income tax consequences of the mergers.  Accordingly, each Aslin Group stockholder should consult its tax advisor with respect to the particular tax consequences of the mergers to such holder.

Tax Consequences of the Mergers Generally to U.S. Holders of Aslin Group Common Stock.  On the basis of the opinion delivered in connection herewith, and subject to the limitations and assumptions described therein:

·                  gain (but not loss) will be recognized by the U.S. holders who receive shares of First Business common stock and cash in exchange for shares of Aslin Group common stock pursuant to the mergers, in an amount equal to the lesser of (1) the amount by which the sum of the fair market value of the First Business common stock and cash received by a U.S. holder of Aslin Group common stock exceeds such holder’s cost basis in its Aslin Group common stock, and (2) the amount of cash received by such holder of Aslin Group common stock (except with respect to any cash received instead of fractional share interests in First Business common stock, as discussed in the section entitled “Cash Received Instead of a Fractional Share of First Business Common Stock”);

·                  the aggregate basis of the First Business common stock received in the merger will be the same as the aggregate basis of the Aslin Group common stock for which it is exchanged, decreased by the amount of cash received in the merger (except with respect to any cash received instead of fractional share interests in First Business common stock), decreased by any basis attributable to fractional share interests in First Business common stock for which cash is received, and increased by the amount of gain recognized on the exchange (regardless of whether such gain is classified as capital gain, or as dividend income, as discussed below, but excluding any gain or loss recognized with respect to fractional share interests in First Business common stock for which cash is received); and

·                  the holding period of First Business common stock received in exchange for shares of Aslin Group common stock will include the holding period of the Aslin Group common stock for which it is exchanged.

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