Washington, DC 20549


Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported):
October 1, 2018

Commission File No. 0-19341

(Exact name of registrant as specified in its charter)

(State or other jurisdiction
of Incorporation or Organization)
(IRS Employer
Identification No.)
Bank of Oklahoma Tower
Boston Avenue at Second Street
Tulsa, Oklahoma
(Address of Principal Executive Offices)
(Zip Code)
(918) 588-6000
(Registrant’s telephone number, including area code)

(Former name or former address, if changes since last report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

|_| Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425).

|_| Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12).

|_| Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)).

|_| Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c)).

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).
¨ Emerging growth company

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ¨

Explanatory Note

On October 1, 2018, BOK Financial Corporation (the "Company") filed a Current Report on Form 8-K (the "Original Form 8-K") disclosing the completion of the previously announced merger with CoBiz Financial Inc., pursuant to the Agreement and Plan of Merger dated as of June 17, 2018 between CoBiz, the Company, and an Oklahoma corporation and wholly owned subsidiary of the Company, BOKF Merger Corporation Number Sixteen.

Under Item 9.01 of the Original Form 8-K, it stated that financial statements of business acquired and pro forma financial information would be filed by amendment no later than 71 days following the date the Original Form 8-K was required to be filed. Upon review of the financial information of the Company and CoBiz Financial Inc., we have determined no additional information is required to be filed or furnished.

Item 9.01. Financial Statements and Exhibits.

(a) Financial Statements of Businesses Acquired.

Not required under Rule 3-05(b) of Regulation S-X as the merger does not meet the definition of a significant acquisition.

(b) Pro Forma Financial Information

Not required under Article 11 of Regulation S-X as the merger does not meet the definition of a significant acquisition.


Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.


By: /s/ Steven E. Nell
Steven E. Nell
Executive Vice President
Chief Financial Officer

Date: December 10, 2018