Ownership Submission
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 *
Hinrichs Liane K
   2. Issuer Name and Ticker or Trading Symbol
MCDERMOTT INTERNATIONAL INC [MDR] 		5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
SrVP, Gen.Counsel & Corp. Sec.
(Last)
(First)
(Middle)
757 N. ELDRIDGE PARKWAY		 3. Date of Earliest Transaction (Month/Day/Year)
03/04/2011
(Street)

HOUSTON, TX 77079		 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
Common Stock 03/04/2011   M   10,185 A $ 0 139,418 D  
Common Stock 03/04/2011   F   2,883 D $ 25.64 136,535 D  
Common Stock 03/05/2011   M   19,168 A $ 0 155,703 D  
Common Stock 03/05/2011   F   6,986 D $ 25.74 148,717 D  
Common Stock 03/08/2011   M   27,202 A $ 5.64 175,919 D  
Common Stock 03/08/2011   S   27,202 D $ 24.9853 (1) 148,717 D  
Common Stock               2,857 I 401K Plan (2)

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
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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
Restricted Stock Units (3) 03/04/2011   M     10,185 03/04/2011(4) 03/04/2011(4) Common Stock 10,185 $ 0 20,371 D  
Restricted Stock Units (3) 03/04/2011   A   10,014     (5)   (5) Common Stock 10,014 $ 0 10,014 D  
Stock Option (right to buy) $ 25.64 03/04/2011   A   22,080     (6) 03/04/2018 Common Stock 22,080 $ 0 22,080 D  
Restricted Stock Units (3) 03/05/2011   M     19,168 03/05/2011(7) 03/05/2011(7) Common Stock 19,168 $ 0 19,169 D  
Employee Stock Option (right to buy) $ 5.64 03/08/2011   M     27,202   (8) 03/05/2016 Common Stock 27,202 $ 0 27,203 D  

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
Hinrichs Liane K
757 N. ELDRIDGE PARKWAY
HOUSTON, TX 77079		       SrVP, Gen.Counsel & Corp. Sec.  

Signatures

 Robert E. Stumpf, by Power of Attorney   03/08/2011
**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) The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $24.9515 to $25.00, inclusive. The reporting person undertakes to provide to McDermott International, Inc., any security holder of McDermott International, Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.
(2) Based upon units held in 401K Plan and the fair market value of MDR common stock as of March 4, 2011.
(3) Each restricted stock unit represents a contingent right to receive one share of MDR common stock.
(4) The restricted stock units vest in three equal annual installments beginning March 4, 2011.
(5) The restricted stock units vest in three equal annual installments beginning March 4, 2012.
(6) The option is exercisable in three equal annual installments beginning March 4, 2012.
(7) The restricted stock units vest in three equal annual installments beginning March 5, 2010.
(8) The option vests in three equal annual installments on March 5, 2010, 2011 and 2012.

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