Initial Statement of Beneficial Ownership (3)

FORM 3	UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES	OMB APPROVAL OMB Number: 3235-0104 Estimated average burden hours per response... 0.5
	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 ^*

FINGER ALISON CECILY

2. Date of Event Requiring Statement (MM/DD/YYYY) 2/14/2018

3. Issuer Name and Ticker or Trading Symbol

bluebird bio, Inc. [BLUE]

(Last) (First) (Middle)

C/O BLUEBIRD BIO, INC., 60 BINNEY STREET

4. Relationship of Reporting Person(s) to Issuer (Check all applicable)

_____ Director _____ 10% Owner
___ X ___ Officer (give title below) _____ Other (specify below)
Chief Commercial Officer /

(Street)

CAMBRIDGE, MA 02142

(City) (State) (Zip)

5. 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 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	834 ⁽¹⁾	D
Common Stock	2750 ⁽²⁾	D
Common Stock	2063 ⁽³⁾	D
Common Stock	6250 ⁽⁴⁾	D
Common Stock	3942 ⁽⁵⁾	D

*Table II - Derivative Securities Beneficially Owned ( e.g.* , puts, calls, warrants, options, convertible securities)**
1. Title of Derivate Security (Instr. 4)	2. Date Exercisable and Expiration Date (MM/DD/YYYY)		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)
1. Title of Derivate Security (Instr. 4)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares	4. Conversion or Exercise Price of Derivative Security		6. Nature of Indirect Beneficial Ownership (Instr. 5)
Stock Option (Right to buy)	⁽⁶⁾	9/1/2025	Common Stock	25000	$128.86	D
Stock Option (Right to buy)	⁽⁷⁾	3/1/2026	Common Stock	22000	$50.51	D
Stock Option (Right to buy)	⁽⁸⁾	2/1/2027	Common Stock	11000	$75.60	D
Stock Option (Right to buy)	⁽⁹⁾	2/1/2028	Common Stock	25000	$205.25	D

Explanation of Responses:
(1)	Restricted stock units for common stock vest over a three-year period at a rate of 33% on August 17, 2016; 33% on August 17, 2017; and 34% on August 17, 2018.
(2)	Restricted stock units for common stock vest over a four-year period at a rate of 25% on January 1, 2017, 25% on January 1, 2018, 25% on January 1, 2019, and 25% on January 1, 2020.
(3)	Restricted stock units for common stock vest over a four-year period at a rate of 25% on January 4, 2018, 25% on January 4, 2019, 25% on January 4, 2020, and 25% on January 4, 2021.
(4)	Restricted stock units for common stock vest over a four-year period at a rate of 25% on January 4, 2019, 25% on January 4, 2020, 25% on January 4, 2021, and 25% on January 4, 2022.
(5)	648 shares were acquired under the bluebird bio, Inc. employee stock purchase plan.
(6)	This option vests over a four-year period, at a rate of twenty-five percent (25%) on August 17, 2016 and in 36 equal monthly installments thereafter.
(7)	This option vests over a four-year period, at a rate of twenty-five percent (25%) on January 1, 2017, and in 36 equal monthly installments.
(8)	This option vests over a four-year period, at a rate of twenty-five percent (25%) on January 4, 2018 and in 36 equal monthly installments thereafter.
(9)	This option vests over a four-year period, at a rate of twenty-five percent (25%) on January 4, 2019, and in 36 equal monthly installments.

Reporting Owners
Reporting Owner Name / Address	Relationships
Reporting Owner Name / Address	Director	10% Owner	Officer	Other
FINGER ALISON CECILY C/O BLUEBIRD BIO, INC. 60 BINNEY STREET CAMBRIDGE, MA 02142			Chief Commercial Officer

Signatures
/s/ Jason F. Cole - Attorney-in-fact		2/20/2018
^** 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 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).
Note:	File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB control number.