FORM 3

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 INITIAL STATEMENT OF 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 *   Rohrbacker Leslie C 2. Date of Event Requiring Statement (Month/Day/Year) 02/09/2010 3. Issuer Name and Ticker or Trading Symbol MEDICINES CO /DE [MDCO] (Last) (First) (Middle) 8 SYLVAN WAY 4. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director _____ 10% Owner __X__ Officer (give title below) _____ Other (specify below) VP, Chief Human Strategy Offic 5. If Amendment, Date Original Filed(Month/Day/Year) (Street) PARSIPPANY, NJ 07054 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 Beneficially Owned

1.Title of Security (Instr. 4) 2. Amount of Securities Beneficially Owned (Instr. 4) 3. Ownership Form: Direct (D) or Indirect (I) (Instr. 5) 4. Nature of Indirect Beneficial Ownership (Instr. 5) Common Stock 3,855 (1) D Â

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.			SEC 1473 (7-02)
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Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)

1. Title of Derivative Security (Instr. 4)	2. Date Exercisable and Expiration Date (Month/Day/Year)		3. Title and Amount of Securities Underlying Derivative Security (Instr. 4)		4. Conversion or Exercise Price of Derivative Security	5. Ownership Form of Derivative Security: Direct (D) or Indirect (I) (Instr. 5)	6. Nature of Indirect Beneficial Ownership (Instr. 5)
	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Option (right to buy)	  (2)	12/05/2015	Common Stock	20,000	$ 18.65	D	Â
Option (right to buy)	  (3)	02/16/2017	Common Stock	6,052	$ 28.6	D	Â
Option (right to buy)	  (4)	02/15/2018	Common Stock	7,825	$ 19.36	D	Â
Option (right to buy)	  (5)	03/03/2018	Common Stock	20,000	$ 18.39	D	Â
Option (right to buy)	  (6)	02/20/2019	Common Stock	2,956	$ 13.95	D	Â
Option (right to buy)	  (7)	06/01/2019	Common Stock	10,000	$ 7.61	D	Â

Reporting Owners

Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
Rohrbacker Leslie C 8 SYLVAN WAY PARSIPPANY, NJ 07054	Â	Â	  VP, Chief Human Strategy Offic	Â

Signatures

/s/Leslie C. Rohrbacker		02/17/2010
**Signature of Reporting Person		Date

Explanation of Responses:

*	If the form is filed by more than one reporting person, see Instruction 5(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)	As of 2/9/2010 the shares of restricted stock (3,855 granted on 2/20/2009) were not vested. The shares vest 25% annually ending 2/20/2013.
(2)	As of 2/9/2010, the original grant (25,000 granted on 12/5/2005) was fully vested with 5,000 options having been exercised.
(3)	As of 2/9/2010, the original grant (6,052 granted on 2/16/2007) was vested with respect to 4,413 of the shares covered thereby, none of which options have been exercised. The remaining 1,639 shares covered by this option vest in equal monthly installments ending 2/16/2011.
(4)	As of 2/9/2010, the orginal grant (7,825 granted on 2/15/2008) was vested with respect to 3,749 of the shares covered thereby, none of which options have been exercised. The remaining 4,076 shares covered by this option vest in equal monthly installments ending on 2/15/2012.
(5)	As of 2/9/2010, the original grant (20,000 granted on 3/3/2008) was vested with respect to 9,583 of the shares covered thereby, none of which options have been exercised. The remaining 10,417 shares covered by this option vest in equal monthly installments ending on 3/3/2012.
(6)	As of 2/9/2010, the original grant (2,956 granted on 2/20/2009) was vested with respect to 677 of the shares covered thereby, none of which options have been exercised. The remaining 2,279 shares covered by this option vest in equal monthly installments ending 2/20/2013.
(7)	As of 2/9/2010, the original grant (10,000 granted on 6/1/2009) was vested with respect to 1,667 of the shares covered thereby, none of which options have been exercised. The remaining 8,333 shares covered by this option vest in equal monthly installments ending on 6/1/2013.

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