bluebird bio(BLUE) - 2020 Q1 - Quarterly Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, DC 20549 __________________________________________________________________ FORM 10-Q __________________________________________________________________ (Mark One) ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended March 31, 2020 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: ...