Ownership Submission
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 *
  Tasker Seth A
2. Date of Event Requiring Statement (Month/Day/Year)
07/22/2016
3. Issuer Name and Ticker or Trading Symbol
INFINITY PHARMACEUTICALS, INC. [INFI]
(Last)
(First)
(Middle)
C/O INFINITY PHARMACEUTICALS, INC., 784 MEMORIAL DRIVE
4. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
General Counsel
5. If Amendment, Date Original Filed(Month/Day/Year)
(Street)

CAMBRIDGE, MA 02139
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 3,525.45
I
By 401(k)

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
Stock Option (Right to Buy) 12/04/2008(1) 12/04/2018 Common Stock 1,190 $ 7.18 D  
Stock Option (Right to Buy) 01/05/2010(2) 01/05/2020 Common Stock 631 $ 6.25 D  
Stock Option (Right to Buy) 03/09/2010(2) 03/09/2020 Common Stock 2,000 $ 6.39 D  
Stock Option (Right to Buy) 01/06/2011(2) 01/06/2021 Common Stock 1,713 $ 5.94 D  
Stock Option (Right to Buy) 01/06/2012(2) 01/06/2022 Common Stock 2,240 $ 7.93 D  
Stock Option (Right to Buy)   (3) 08/14/2022 Common Stock 1,000 $ 16.57 D  
Stock Option (Right to Buy)   (4) 01/04/2023 Common Stock 4,730 $ 36.85 D  
Stock Option (Right to Buy)   (5) 03/06/2023 Common Stock 2,000 $ 45.24 D  
Stock Option (Right to Buy)   (6) 01/10/2024 Common Stock 6,711 $ 12.91 D  
Stock Option (Right to Buy)   (7) 08/25/2024 Common Stock 10,000 $ 11.24 D  
Stock Option (Right to Buy)   (8) 01/14/2025 Common Stock 8,214 $ 15.74 D  
Stock Option (Right to Buy)   (9) 03/19/2025 Common Stock 5,300 $ 16.53 D  
Stock Option (Right to Buy)   (10) 01/06/2026 Common Stock 11,938 $ 6.71 D  

Reporting Owners

Reporting Owner Name / Address Relationships
Director 10% Owner Officer Other
Tasker Seth A
C/O INFINITY PHARMACEUTICALS, INC.
784 MEMORIAL DRIVE
CAMBRIDGE, MA 02139
      General Counsel  

Signatures

/s/ Seth A. Tasker 07/29/2016
**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) The option vested as to 12/48th of the shares on December 4, 2008 and vested as to 1/48th of the shares at the end of each calendar month thereafter. The option has fully vested.
(2) The option vested in equal monthly installments over four years beginning at the end of the calendar month during which the grant was made. The option has fully vested.
(3) The option vests as to 1/48th of the shares on August 31, 2012 and vests as to 1/48th of the shares at the end of each calendar month thereafter.
(4) The option vests as to 1/48th of the shares on January 31, 2013 and vests as to 1/48th of the shares at the end of each calendar month thereafter.
(5) The option vests as to 1/48th of the shares on March 31, 2013 and vests as to 1/48th of the shares at the end of each calendar month thereafter.
(6) The option vests as to 1/48th of the shares on January 31, 2014 and vests as to 1/48th of the shares at the end of each calendar month thereafter.
(7) The option vests as to 1/48th of the shares on August 31, 2014 and vests as to 1/48th of the shares at the end of each calendar month thereafter.
(8) The option vests as to 1/48th of the shares on January 31, 2015 and vests as to 1/48th of the shares at the end of each calendar month thereafter.
(9) The option vests as to 1/48th of the shares on March 31, 2015 and vests as to 1/48th of the shares at the end of each calendar month thereafter.
(10) The option vests as to 1/48th of the shares on January 31, 2016 and vests as to 1/48th of the shares at the end of each calendar month thereafter.

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