X0306 4 2022-01-10 false 0001293971 bluebird bio, Inc. BLUE 0001578408 Leschly Nick C/O BLUEBIRD BIO, INC. 60 BINNEY STREET CAMBRIDGE MA 02142 true false false false Common Stock 2022-01-10 4 S false 2369.00 9.4022 D 286398.00 D Common Stock 2022-01-11 4 S false 5068.00 9.6426 D 281330.00 D Common Stock 45699.00 I Nick Leschly 2001 Trust Common Stock 123000.00 I Nick Leschly Irrevocable GST Trust of 2019 Shares were sold to cover tax withholding obligations incurred in connection with the vesting of Restricted Stock Units. The range in prices for the transaction reported on this line was $9.385 to $9.42. The average weighted price was $9.4022. The reporting person will provide, upon request by the SEC, the issuer or security holder of the issuer, full information regarding the number of shares sold at each separate price. The range in prices for the transaction reported on this line was $9.48 to $9.83. The average weighted price was $9.6426. The reporting person will provide, upon request by the SEC, the issuer or security holder of the issuer, full information regarding the number of shares sold at each separate price. /s/ Helen C. Fu, Attorney-in-Fact 2022-01-12