FORM 4 Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940

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(Print or Type Responses)

1. Name and Address of Reporting Person * DEMSHUR DAVID M   2. Issuer Name and Ticker or Trading Symbol CORE LABORATORIES N V [CLB] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) __X__ Director _____ 10% Owner __X__ Officer (give title below) _____ Other (specify below) President & CEO (Last) (First) (Middle) 6316 WINDFERN 3. Date of Earliest Transaction (Month/Day/Year) 03/23/2005 (Street) HOUSTON, TX 77040 4. If Amendment, Date Original Filed(Month/Day/Year) 6. Individual or Joint/Group Filing(Check Applicable Line) _X_ Form filed by One Reporting Person ___ Form filed by More than One Reporting Person (City) (State) (Zip) Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned

1.Title of Security (Instr. 3) 2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code (Instr. 8) 4. Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5) 5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4) 6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4) 7. Nature of Indirect Beneficial Ownership (Instr. 4) Code V Amount (A) or (D) Price

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Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)

1. Title of Derivative Security (Instr. 3)

2. Conversion or Exercise Price of Derivative Security

3. Transaction Date (Month/Day/Year)

3A. Deemed Execution Date, if any (Month/Day/Year)

4. Transaction Code (Instr. 8)

5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4, and 5)

6. Date Exercisable and Expiration Date (Month/Day/Year)

7. Title and Amount of Underlying Securities (Instr. 3 and 4)

8. Price of Derivative Security (Instr. 5)

9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)

10. Ownership Form of Derivative Security: Direct (D) or Indirect (I) (Instr. 4)

11. Nature of Indirect Beneficial Ownership (Instr. 4)

Code

V

(A)

(D)

Date Exercisable

Expiration Date

Title

Amount or Number of Shares

Performance Shares (1) (2)

$ 0 (3)

03/23/2005

A

40,000

12/31/2007

12/31/2007

Common Shares

40,000

$ 0

40,000

D

Reporting Owners

Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
DEMSHUR DAVID M 6316 WINDFERN HOUSTON, TX 77040	X		President & CEO

Signatures

/s/ John D. Denson, Attorney-in-fact		03/24/2005
**Signature of Reporting Person		Date

Explanation of Responses:

*	If the form is filed by more than one reporting person, see Instruction 4(b)(v).
**	Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1)	Represent contingent rights to acquire common shares ("Performance Shares") that are subject to a performance goal that is based on a calculated return on equity versus a pre-determined target return on equity of 20%. The return on equity is calculated by dividing earnings before interest and income tax from continuing operations over the performance period by ending shareholders' equity over the performance period ("ROE"). Unless there is a change in control, none of these shares will be issued if the ROE for Core Laboratories N.V. ("Core") is less than 20% for the three-year performance period.
(2)	If Core's ROE for the performance period equals 20%, then 50% of the shares will be issued, and if Core's ROE for the performance period equals or exceeds 24%, then 100% of the shares will be issued. If Core's ROE for the performance period is greater than 20% but less than 24%, then the number of shares to be issued would be interpolated based on the terms of the agreement. If a change in control of Core occurs prior to the last day of the performance period and while the executive officer is employed by Core, then all of the executive officer's Performance Shares will vest as of the date of the change in control.
(3)	1 for 1

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