Acceleron Pharma Inc.
ACCELERON PHARMA INC (Form: 4, Received: 03/14/2017 18:21:21)
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
                                                                                  
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Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940
                      

1. Name and Address of Reporting Person *

George Jean
2. Issuer Name and Ticker or Trading Symbol

ACCELERON PHARMA INC [ XLRN ]
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)

C/O ADVANCED TECHNOLOGY VENTURES, 500 BOYLSTON STREET SUITE 1380
3. Date of Earliest Transaction (MM/DD/YYYY)

3/2/2017
(Street)

BOSTON, MA 02116
(City)        (State)        (Zip)
4. If Amendment, Date Original Filed (MM/DD/YYYY)

 
6. Individual or Joint/Group Filing (Check Applicable Line)

_ X _ Form filed by One Reporting Person
___ Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1.Title of Security
(Instr. 3)
2. Trans. Date 2A. Deemed Execution Date, if any 3. Trans. 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   3/2/2017     A    1250   A $0   1250   D    
Common Stock                  105122   (1) I   See footnote   (2)

Table II - Derivative Securities Beneficially Owned ( e.g. , puts, calls, warrants, options, convertible securities)
1. Title of Derivate Security
(Instr. 3)
2. Conversion or Exercise Price of Derivative Security 3. Trans. Date 3A. Deemed Execution Date, if any 4. Trans. 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 7. Title and Amount of Securities Underlying Derivative Security
(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
Option to Purchase Common Stock   $30.17   3/2/2017     A      7500         (3) 3/2/2027   Common Stock   7500   $0   7500   D    

Explanation of Responses:
( 1)  Represents 98,674 shares, 3,959 shares, 1,902 shares and 587 shares of common stock held by Advanced Technology Ventures VII, L.P. ("ATV VII"), Advanced Technology Ventures VII (B), L.P. ("ATV VII B"), Advanced Technology Ventures VII (C), L.P. ("ATV VII C") and ATV Entrepreneurs VII, L.P. ("ATV VII E"), respectively.
( 2)  ATV Associates VII, L.L.C. ("ATV A VII") is the general partner of ATV VII, ATV VII B, ATV VII C and ATV VII E and exercises voting and dispositive authority over the shares held by ATV VII, ATV VII B, ATV VII C and ATV VII E. Jean George is a managing director of ATV A VII and exercises voting and dispositive decisions of ATV A VII collectively with each of four other managing directors. Ms. George disclaims beneficial ownership of these securities and this report shall not be deemed an admission that she is the beneficial owner of such securities for purposes of Section 16 or for any other purpose, except to the extent of her pecuniary interest therein.
( 3)  The shares of common stock underlying this stock option award vest in full on the one year anniversary of the grant date.

Reporting Owners
Reporting Owner Name / Address
Relationships
Director 10% Owner Officer Other
George Jean
C/O ADVANCED TECHNOLOGY VENTURES
500 BOYLSTON STREET SUITE 1380
BOSTON, MA 02116
X



Signatures
/s/ John D. Quisel, as attorney-in-fact for Jean M. George 3/14/2017
** Signature of Reporting Person Date


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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