Viking Global Investors

BBIOACTIVIST

Bridgebio Pharma, Inc.

Item 4 of the Schedule 13D is hereby amended and supplemented as follows: The response to Item 5(c) of this Amendment No. 12 is incorporated by reference herein.

LABACTIVIST

Standard Biotools Inc.

The response to Item 3 of this Schedule 13D is incorporated by reference herein. On June 6, 2026, the Issuer, Treeline Biosciences, Inc., a Delaware corporation ("Treeline"), and Siri Merger Sub, Inc., a Delaware corporation and a wholly owned subsidiary of the Issuer ("Merger Sub"), entered into an Agreement and Plan of Merger and Reorganization (the "Merger Agreement"), pursuant to which, among other matters, and subject to the satisfaction or waiver of the conditions set forth in the Merger Agreement, Merger Sub will merge with and into Treeline, with Treeline continuing as a wholly owned subsidiary of the Issuer and the surviving corporation of the merger (the "Merger"). Upon the terms and subject to the conditions set forth in the Merger Agreement, at the effective time of the Merger ("Effective Time"), each share of capital stock of Treeline will be converted into the right to receive a number of shares of Common Stock in accordance with the Exchange Ratio (as defined in the Merger Agreement). Also on June 6, 2026, in connection with the Merger Agreement, the Issuer, Treeline and Merger Sub entered into a voting agreement (the "Voting Agreement") with VGOP and VGOD. Pursuant to the Voting Agreement, VGOP and VGOD have agreed, among other things, subject to the terms and conditions thereof, to: (i) vote their beneficially owned securities of the Issuer: (1) in favor of the approval of (i) the issuance of Common Stock to holders of Treeline stock pursuant to the Merger Agreement, (ii) an amendment to the Issuer's charter pursuant to which the name of Issuer will be changed to "Treeline Biosciences Holdings, Inc.", (iii) a reverse stock split of all outstanding shares of Common Stock at a reverse stock split ratio mutually agreed to by Treeline and the Issuer, and (iv) the adoption of the Post-Closing Equity Incentive Plan and Post-Closing ESPP (each as defined in the Merger Agreement); (2) in favor of any proposal to adjourn to a later date if there is not a quorum or sufficient affirmative votes (in person or by proxy) for approval of any such matters on the date on which the meeting is held; (3) against any action or agreement that would reasonably be expected to result in the conditions set forth in the Merger Agreement not being fulfilled or a breach of a covenant, representation or warranty or any other material obligation or agreement of the Issuer contained in the Merger Agreement; (4) against any action, proposal, transaction or agreement that would reasonably be expected to prevent or materially delay the consummation of the transactions contemplated by the Merger Agreement or the fulfillment of the Issuer's or Merger Sub's conditions to closing under the Merger Agreement; and (5) against any third party acquisition transactions; and (ii) comply with certain restrictions on the disposition of such shares, in each case subject to the terms and conditions contained therein. The maximum number of shares of Common Stock beneficially owned by VGOP and VGOD subject to the Voting Agreement shall not at any time exceed 58,651,170 shares of Common Stock or other voting securities of the Issuer (the "Covered Shares Cap"). The foregoing description of the Voting Agreement does not purport to be complete and is qualified in its entirety by reference to the form of the Voting Agreement, which is filed as an exhibit to this Schedule 13D, and is incorporated by reference herein. The Reporting Persons acquired shares of Common Stock for investment purposes, and such purchases were made in the Reporting Persons' ordinary course of business. This Schedule 13D amends the statement on Schedule 13G filed by the Reporting Persons to report their beneficial ownership of the shares of Common Stock, as most recently amended on May 15, 2026. The Reporting Persons are filing this Schedule 13D, pursuant to Rule 13d-1(e) under the Act, solely as a result of their entering into the Voting Agreement. As such, the Reporting Persons currently are subject to a "cooling-off" period pursuant to Rule 13d-1(e)(2) under the Act, which ends at the expiration of the tenth day from the date of the filing of this Schedule 13D. The Reporting Persons expect to review from time to time their investment in the Issuer and may, depending on the Issuer's business, assets, operations, financial condition and/or prospects, legal, regulatory and/or contractual restrictions (such as the expiration of the cooling-off period and the transfer restrictions in the Voting Agreement) and other factors: (i) purchase additional shares of Common Stock, options or other securities of the Issuer in the open market, in privately negotiated transactions or otherwise; (ii) sell all or a portion of the shares of Common Stock, options or other securities now beneficially owned or hereafter acquired by them; (iii) enter into hedging transactions with respect to the shares of Common Stock, options or other securities of the Issuer now beneficially owned or hereafter acquired by them; (iv) engage in communications with, without limitation, one or more holders of the Issuer's securities or derivatives, officers of the Issuer, members of the Issuer's board of directors, advisors, potential strategic partners, investment professionals, and/or other persons regarding the Merger or the Issuer more generally, including but not limited to its operations, governance, and control; and (v) engage in such other proposals as the Reporting Persons may deem appropriate under the circumstances, including plans or proposals which may relate to, or could result in, any of the matters referred to in clauses (a) through (j) of Item 4 of Schedule 13D.