Description of the business

9 Months Ended

Sep. 30, 2014

Organization Consolidation And Presentation Of Financial Statements [Abstract]

Description of the business

1. Description of the business

bluebird bio, Inc. (the “Company” or “bluebird”) was incorporated in Delaware on April 16, 1992, and is headquartered in Cambridge, Massachusetts. The Company was formed to develop, manufacture and market therapies to safely and effectively deliver genes useful in the treatment of serious human diseases. Since its inception, the Company has devoted substantially all of its resources to its development efforts relating to its product candidates, including activities to manufacture product in compliance with good manufacturing practices (“GMP”), conduct clinical studies of its product candidates, provide general and administrative support for these operations and protect its intellectual property.

On June 30, 2014, the Company acquired all of the outstanding capital stock of Precision Genome Engineering, Inc. (“Pregenen”) and in connection therewith, obtained the rights to Pregenen’s gene editing and cell signaling technology. See Note 7, “Business combinations,” for additional information.

In July 2014, the Company sold 3,450 shares of common stock (inclusive of 450 shares of common stock sold by the Company pursuant to the full exercise of an overallotment option granted to the underwriters in connection with the offering) through an underwritten public offering at a price of $34.00 per share. The aggregate net proceeds received by the Company from the offering were $109,765, net of underwriting discounts and commissions and estimated offering expenses payable by the Company of approximately $7,534.