SC 14D9/A

This Amendment No. 12 (this “Amendment”) amends and supplements the Solicitation/Recommendation Statement on Schedule 14D-9 (as amended or supplemented from time to time, the “Schedule 14D-9”) filed by bluebird bio, Inc., a Delaware corporation (“bluebird” or the “Company”), with the U.S. Securities and Exchange Commission (the “SEC”) on March 7, 2025, relating to the tender offer by Beacon Merger Sub, Inc., a Delaware corporation (“Merger Sub”) and an indirect wholly owned subsidiary of Beacon Parent Holdings, L.P., a Delaware limited partnership (“Parent”), to purchase all of the outstanding Shares in exchange for the consideration per Share, as may be elected by each Company stockholder, between either (but not both) of (a) $3.00 in cash per Share, subject to any applicable withholding taxes and without interest thereon (the “Closing Amount”), plus (b) one contingent value right (each, a “CVR”) per Share, representing the right to receive one contingent payment of $6.84 in cash, subject to any applicable withholding taxes and without interest thereon, payable upon the achievement of the milestone specified in, and subject to and in accordance with the terms and conditions set forth in, the Contingent Value Rights Agreement (the “CVR Agreement”) (the “Cash and CVR Consideration”) or (ii) $5.00 in cash per Share, subject to any applicable withholding taxes and without interest thereon (the “All Cash Closing Amount” or the “All Cash Consideration”) (the consideration per Share elected by the applicable Company stockholder between the Cash and CVR Consideration and the All-Cash Consideration, collectively, or any greater amount per Share that may be paid pursuant to the Offer (as defined below), the “Offer Price”), on the terms and subject to the conditions set forth in the Amended and Restated Offer to Purchase, dated May 14, 2025 (as it may be amended, supplemented or otherwise modified from time to time, the “Offer to Purchase”), and in the related Letter of Election and Transmittal (which, together with the Offer to Purchase, as each may be amended, supplemented or otherwise modified from time to time, constitute the “Offer”). The Offer is described in a Tender Offer Statement on Schedule TO (as amended or supplemented from time to time, the “Schedule TO”) filed by Parent and Merger Sub with the U.S. Securities and Exchange Commission (the “SEC”) on May 14, 2025, as amended. The Offer to Purchase and Letter of Election and Transmittal are filed as Exhibits (a)(1)(A) and (a)(1)(B), respectively, to the Schedule TO and are incorporated herein by reference.

Except to the extent specifically provided in this Amendment, the information set forth in the Schedule 14D-9 remains unchanged. Capitalized terms used, but not otherwise defined, in this Amendment shall have the meanings ascribed to them in the Schedule 14D-9. This Amendment is being filed to reflect certain updates as reflected below.

Unless stated otherwise, the new text in the supplemental information is bolded and underlined and any deleted text is bolded and denoted with a strikethrough to highlight the supplemental information being disclosed.

Item 4. The Solicitation or Recommendation.

Item 4 of the Schedule 14D-9 is hereby amended by adding the bold and underlined language to, and removing the struck through language from, the sixty-ninth paragraph under the heading “Background and Reasons for the Company Board’s Recommendation – Background of the Offer and the Merger” as follows:

On May 12, 2025, following receipt of preliminary tender reports, representatives of Parent reached out to representatives of the Company to express that in light of the preliminary tender results and conversations with the information agent, they were considering an amendment to the Merger Agreement to provide stockholders with a choice to receive either the then-current offer price (i.e., the Cash and CVR Consideration) or $5.00 per Share in cash. That same day, the Transaction Committee convened, with management and representatives of Latham and Leerink Partners in attendance, and discussed the status of the tender offer in light of the anticipated expiration date later that evening and the communication from Parent that they were considering an amendment to the Merger Agreement. Immediately prior to the then-current expiration time of the Offer (which was extended by Parent), approximately 2,502,927 Shares had been tendered.

Item 9. Exhibits.

Item 9 of the Schedule 14D-9 is hereby amended and supplemented by inserting the following exhibit thereto:


Exhibit Number		Description

(a)(5)(FF)		Press Release, dated May 16, 2025 (incorporated by reference to Exhibit (a)(5)(K) to the Schedule TO filed on May 16, 2025 (the “Schedule TO”) by Beacon Merger Sub, Inc., Beacon Midco, Inc., Beacon Parent Holdings, L.P., Beacon General Partner, LLC, Carlyle Partners Growth, L.P., SK Capital Partners VI-A, L.P. and SK Capital Partners VI-B, L.P).

(a)(5)(GG)		Letter to bluebird bio, Inc. Stockholders, dated May 16, 2025 (incorporated by reference to Exhibit (a)(5)(L) to the Schedule TO).

(a)(5)(HH)		Frequently Asked Questions, dated May 16, 2025.


bluebird bio, Inc.

By:		/s/ Andrew Obenshain
Name:		Andrew Obenshain
Title:		President and Chief Executive Officer
Dated:		May 16, 2025