Joseph Vittiglio - 30 May 2025 Form 4 Insider Report for bluebird bio, Inc. (BLUE)

Footnote F1

In connection with the terms of an Agreement and Plan of Merger, dated as of February 21, 2025 (as amended, the "Merger Agreement"), by and among the Issuer, Beacon Parent Holdings, L.P. ("Parent") and Beacon Merger Sub, Inc., an indirect wholly owned subsidiary of Parent ("Purchaser"), Purchaser completed a tender offer for shares of the Issuer's Common Stock. Tendering stockholders were given the option to receive per share consideration of either (x) $3.00 in cash per share, subject to any applicable withholding taxes and without interest thereon, plus one contingent value right ("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, upon achievement of the specified milestone or (y) $5.00 in cash per share, subject to any applicable withholding taxes and without interest thereon (collectively, the "Offer Price").

Footnote F2

(Continued from footnote 1) After completion of the tender offer, Purchaser merged with and into the Issuer (the "Merger"), effective as of June 2, 2025 (the "Effective Time"), with the Issuer continuing as the surviving entity and a wholly owned subsidiary of Parent.

Footnote F3

Pursuant to the terms of the Merger Agreement, immediately prior to the Effective Time, each time-based restricted stock unit award with respect to shares that is, at the time of determination, subject to vesting or forfeiture conditions and that is not a PSU Award (as defined below) (but including, for clarity, any PSU Award that is subject solely to service-based vesting conditions as of the Effective Time) ("RSU Award") that is outstanding as of immediately prior thereto, shall (a) accelerate and become fully vested, and (b) by virtue of the Merger automatically (except as otherwise provided in the Merger Agreement) and without any action on the part of the Issuer, Parent or the holder thereof, be canceled and terminated and converted into the right to receive

Footnote F4

(Continued from footnote 3) (i) an amount in cash equal to the product of the number of shares underlying such RSU Award immediately prior to the Effective Time and $3.00 in cash, subject to any applicable withholding taxes and without interest thereon plus (ii) one CVR with respect to each share subject to such RSU Award immediately prior to the Effective Time.

Footnote F5

Pursuant to the terms of the Merger Agreement, immediately prior to the Effective Time, each performance-based restricted stock unit award with respect to shares that is, at the time of determination, subject to performance-based vesting or forfeiture conditions ("PSU Award") that is outstanding and vested as of immediately prior thereto, or which shall become vested as required under the terms governing the PSU Award, shall by virtue of the Merger automatically and (except as otherwise provided in the Merger Agreement) without any action on the part of the Issuer, Parent or the holder thereof, be canceled and terminated and converted into the right to receive

Footnote F6

(Continued from footnote 5) (i) an amount in cash equal to the product of the number of shares underlying such PSU Award immediately prior to the Effective Time (assuming that the applicable performance goals have been deemed to be achieved at the greater of target and actual level of performance as determined by the Compensation Committee of the Issuer's board of directors in its discretion) and $3.00 in cash, subject to any applicable withholding taxes and without interest thereon plus (ii) one CVR with respect to each such share subject to such PSU Award immediately prior to the Effective Time.