On September 30, 2024, BlackRock, Inc. filed a Schedule 13G with the Securities and Exchange Commission, disclosing an 8.0% ownership stake in bluebird bio, Inc., amounting to 15,443,767 shares. This filing indicates that BlackRock has sole voting power over 15,230,542 shares and sole dispositive power over all 15,443,767 shares. The filing was made under Rule 13d-1(b), identifying BlackRock as a parent holding company or control person. The address of bluebird bio's principal executive offices is listed as 455 Grand Union Boulevard, Somerville, MA 02145. The filing includes a certification by BlackRock, Inc. that the shares were acquired in the ordinary course of business and not with the purpose of changing or influencing the control of the issuer. The document was signed by Spencer Fleming, Attorney-In-Fact for BlackRock, Inc., on November 8, 2024.

On September 30, 2024, BlackRock, Inc. filed a Schedule 13G with the Securities and Exchange Commission, disclosing an 8.0% ownership stake in bluebird bio, Inc., amounting to 15,443,767 shares. This filing indicates that BlackRock has sole voting power over 15,230,542 shares and sole dispositive power over all 15,443,767 shares. The filing was made under Rule 13d-1(b), identifying BlackRock as a parent holding company or control person. The address of bluebird bio's principal executive offices is listed as 455 Grand Union Boulevard, Somerville, MA 02145. The filing includes a certification by BlackRock, Inc. that the shares were acquired in the ordinary course of business and not with the purpose of changing or influencing the control of the issuer. The document was signed by Spencer Fleming, Attorney-In-Fact for BlackRock, Inc., on November 8, 2024.