UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

SCHEDULE 13D

Under the Securities Exchange Act of 1934

(Amendment No. 3)*

Bolt Biotherapeutics, Inc.

(Name of Issuer)

Common Stock, par value $0.00001 per share

(Title of Class of Securities)

097702 104

(CUSIP Number)

Barbara Fiorini Due

Novo Holdings A/S

Tuborg Havnevej 19

Hellerup, Denmark DK-2900

+45 3527 6592

Copy to:

B. Shayne Kennedy, Esq.

Latham & Watkins LLP

650 Town Center Drive, 20^{th Floor}

Costa Mesa, CA 92626

Telephone: (714) 540-1235

(Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications)

September 27, 2022

(Date of Event which Requires Filing of this Statement)

If the filing person has previously filed a statement on Schedule 13G to report the acquisition which is subject of this Schedule 13D, and is filing this statement because of Rule 13d-1(e), 13d-1(f) or 13d-1(g), check the following box.   ☐

Note: Schedules filed in paper format shall include a signed original and five copies of the schedule, including all exhibits. See Rule 13d-7(b) for other parties to whom copies are to be sent.

The information required on the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (the “Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

CUSIP No.: 097702 104

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This amendment (“Amendment No. 3”) amends the Schedule 13D originally filed with the SEC on February 11, 2021, as subsequently amended by Amendment No. 1 filed on November 22, 2021 and Amendment No. 2 filed on July 15, 2022 (collectively, the “Schedule”). All capitalized terms contained herein but not otherwise defined shall have the meanings ascribed to such terms in the Schedule.

The name of each director and executive officer of both Novo Holdings A/S and the Foundation is set forth on Schedule I to this Amendment No. 3.

The residence or business address of each director and executive officer of both Novo Holdings A/S and the Foundation is set forth on Schedule I to this Schedule 13D.

The Foundation is a Danish self-governing and profit-making foundation, whose objectives are to provide a stable basis for commercial and research activities undertaken by the group of Novo companies and to support scientific, humanitarian and social purposes through grants.

Novo Holdings A/S purchased the Issuer securities based on its belief that the Issuer securities, when purchased, constituted an attractive investment opportunity. Depending upon overall market conditions, other investment opportunities available to Novo Holdings A/S, and the availability of Issuer securities at prices that would make the purchase or sale of such securities desirable, Novo Holdings A/S may endeavor to increase or decrease its position in the Issuer through, among other things, the purchase or sale of Issuer securities on the open market or in private transactions or otherwise, on such terms and at such times as Novo Holdings A/S may deem advisable.

Novo Holdings A/S does not have any present plan or proposal which would relate to or result in any of the matters set forth in subparagraphs (a) - (j) of Item 4 of Schedule 13D except as set forth herein or such as would occur upon or in connection with completion of, or following, any of the actions discussed herein. Depending on various factors including, without limitation, the Issuer’s financial position, results and strategic direction, actions taken by the Issuer’s management and Board of Directors (the “Board”), other investment opportunities available to Novo Holdings A/S, the price levels of the Issuer securities, conditions in the securities markets and general economic and industry conditions, Novo Holdings A/S may in the future take such actions with respect to its investment in the Issuer as it deems appropriate including, without limitation, engaging in communications and information exchanges

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with the Issuer’s management and Board, engaging in discussions with shareholders of the Issuer or other third parties about the Issuer and Novo Holdings A/S’s investment, making recommendations concerning changes to the Issuer’s operations, governance or capitalization, potential business combinations or dispositions involving the Issuer or certain of its businesses, or suggestions for improving the Issuer’s financial and/or operational performance, acquiring additional Issuer securities, disposing of some or all of such securities, or changing its intention with respect to any and all matters referred to in Item 4.

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SIGNATURE

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

Schedule I

Information regarding each director and executive officer of both Novo Holdings A/S and the Novo Nordisk Foundation is set forth below.

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