Sec Form 4 Filing - TEPPER ROBERT I @ bluebird bio, Inc. - 2014-09-11

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
TEPPER ROBERT I
2. Issuer Name and Ticker or Trading Symbol
bluebird bio, Inc. [ BLUE]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
X __ Director X __ 10% Owner
_____ Officer (give title below) _____ Other (specify below)
(Last) (First) (Middle)
C/O THIRD ROCK VENTURES, LLC, 29 NEWBURY STREET, 3RD FLOOR
3. Date of Earliest Transaction (MM/DD/YY)
09/11/2014
(Street)
BOSTON, MA02116
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 09/11/2014 S 87,000 D $ 36.52 ( 1 ) 2,329,974 I See footnote ( 2 )
Common Stock 09/11/2014 J( 3 ) 1,076,920 D $ 0 1,253,054 I See footnote ( 2 )
Common Stock 09/11/2014 J( 4 ) 79,062 A $ 0 79,062 I See footnote ( 5 )
Common Stock 09/11/2014 J( 6 ) 79,062 D $ 0 0 I See footnote ( 5 )
Common Stock 09/11/2014 J( 7 ) 11,449 A $ 0 26,538 D
Common Stock 09/12/2014 S 38,000 D $ 36.59 ( 8 ) 1,215,054 I See footnote ( 2 )
Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
( e.g. , puts, calls, warrants, options, convertible securities)
1. Title of Derivat ive 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
Reporting Owners
Reporting Owner Name / Address Relationships
Director 10% Owner Officer Other
TEPPER ROBERT I
C/O THIRD ROCK VENTURES, LLC
29 NEWBURY STREET, 3RD FLOOR
BOSTON, MA02116
X X
Signatures
/s/ Kevin Gillis by Power of Attorney for Robert I. Tepper, MD 09/12/2014
Signature of Reporting Person Date
Explanation of Responses:
( 1 )The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $36.00 to $36.95, inclusive. The Reporting Person undertakes to provide to bluebird bio Inc., any security holder of bluebird bio Inc., or the staff of the Securities and Exchange Commission (the "SEC"), upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.
( 2 )The shares are directly held by Third Rock Ventures, L.P. ("TRV"). The general partner of TRV is Third Rock Ventures GP, L.P. ("TRV GP"). The general partner of TRV GP is TRV GP, LLC ("TRV GP LLC") and, as such, each of TRV GP and TRV GP LLC exercises shared voting and investment power over the shares held of record by TRV. As a manager of TRV GP LLC, the Reporting Person disclaims beneficial ownership of the shares except to the extent of his pecuniary interest therein, if any.
( 3 )Distribution of shares in kind by TRV on a pro rata basis to its partners.
( 4 )TRV GP received shares distributed in kind by TRV on a pro rata basis to its partners.
( 5 )The shares are directly held by TRV GP. As such, TRV GP LLC and the Reporting Person, exercises voting and investment power over the shares held of record by TRV GP. The Reporting Person disclaims beneficial ownership of the shares except to the extent of his pecuniary interest therein, if any.
( 6 )Distribution of shares in kind by TRV GP on a pro rata basis to its partners.
( 7 )The Reporting Person received shares distributed in kind by TRV GP on a pro rata basis to its partners.
( 8 )The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $36.25 to $37.005, inclusive. Each Reporting Person undertakes to provide to bluebird bio Inc., any security holder of bluebird bio Inc., or the staff of the SEC, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

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