Sec Form 4 Filing - Rosenberg Martin @ CUBIST PHARMACEUTICALS INC - 2012-01-03

Insider filing report for Changes in Beneficial Ownership
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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
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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1. Name and Address of Reporting Person
Rosenberg Martin
2. Issuer Name and Ticker or Trading Symbol
CUBIST PHARMACEUTICALS INC [ CBST]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
X __ Director _____ 10% Owner
_____ Officer (give title below) _____ Other (specify below)
(Last) (First) (Middle)
65 HAYDEN AVENUE
3. Date of Earliest Transaction (MM/DD/YY)
01/03/2012
(Street)
LEXINGTON, MA02421
4. If Amendment, Date Original Filed (MM/DD/YY)
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 (MM/DD/YY) 2A. Deemed Execution Date, if any (MM/DD/YY) 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 01/03/2012 M 2,500 A $ 21.88 7,158 D
Common Stock 01/03/2012 M 7,500 A $ 18.22 14,658 D
Common Stock 01/03/2012 S( 1 ) 10,000 D $ 40.0822 ( 2 ) 4,658 D
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 (MM/DD/YY) 3A. Deemed Execution Date, if any (MM/DD/YY) 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
(MM/DD/YY)
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
Stock Options (Right to Buy) $ 21.88 01/03/2012 M 2,500 06/07/2008( 3 ) 06/07/2017 Common Stock 2,500 $ 0 12,500 D
Stock Options (Right to Buy) $ 18.22 01/03/2012 M 7,500 06/04/2010( 4 ) 06/04/2019 Common Stock 7,500 $ 0 0 D
Reporting Owners
Reporting Owner Name / Address Relationships
Director 10% Owner Officer Other
Rosenberg Martin
65 HAYDEN AVENUE
LEXINGTON, MA02421
X
Signatures
/s/ Benjamin S. Harshbarger - Attorney in fact 01/04/2012
Signature of Reporting Person Date
Explanation of Responses:
( 1 )Sold pursuant to a Rule 10(b)5-1 Plan
( 2 )This transaction was executed in multiple trades at prices ranging from $39.82 to $40.42. The price reported in the table reflects the weighted average sale price. The reporting person undertakes to provide upon request to the SEC staff, the issuer or a security holder of the issuer, full information regarding the number of shares and prices at which the transaction was effected.
( 3 )Option vests 100% on one-year anniversary of grant.
( 4 )Options vest 100% on the earlier of the first anniversary of the grant date or the date of the Company's 2010 Annual Meeting of Stockholders.

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* 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).

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