[424B3] Bolt Projects Holdings, Inc. Prospectus Filed Pursuant to Rule 424(b)(3)

Rhea-AI Filing Summary

Bolt Projects Holdings, Inc. filed a Prospectus Supplement No. 2 under Rule 424(b)(3) to update its S-1 prospectus by incorporating its Form 8-K dated October 17, 2025.

According to the 8-K, the Board of Directors approved and adopted amendments to the company’s Amended and Restated Bylaws, effective October 17, 2025. The full text of the amended bylaws is provided as Exhibit 3.1 and incorporated by reference.

Filed pursuant to Rule 424(b)(3)

Registration Statement No. 333-289821

Prospectus Supplement No. 2

(To Prospectus dated September 2, 2025)

BOLT PROJECTS HOLDINGS, INC.

This prospectus supplement updates, amends and supplements the prospectus dated September 2, 2025 (the “Prospectus”), which forms a part of our Registration Statement on Form S-1 (Registration No. 333-289821). Capitalized terms used in this prospectus supplement and not otherwise defined herein have the meanings specified in the Prospectus.

This prospectus supplement is being filed to update, amend and supplement the information included in the Prospectus with the information contained in our Current Report on Form 8-K, filed with the Securities and Exchange Commission (“SEC”) on October 17, 2025, which is set forth below.

This prospectus supplement is not complete without the Prospectus. This prospectus supplement should be read in conjunction with the Prospectus, which is to be delivered with this prospectus supplement, and is qualified by reference thereto, except to the extent that the information in this prospectus supplement updates or supersedes the information contained in the Prospectus. Please keep this prospectus supplement with your Prospectus for future reference.

INVESTING IN OUR SECURITIES INVOLVES CERTAIN RISKS. SEE “RISK FACTORS” BEGINNING ON PAGE 6 OF THE PROSPECTUS.

Neither the SEC nor any state securities commission has approved or disapproved of these securities or determined if the Prospectus or this prospectus supplement is truthful or complete. Any representation to the contrary is a criminal offense.

The date of this prospectus supplement is October 17, 2025

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

PURSUANT TO SECTION 13 OR 15(d)

OF THE SECURITIES EXCHANGE ACT OF 1934

Date of Report (Date of earliest event reported): October 17, 2025

Bolt Projects Holdings, Inc.

(Exact name of registrant as specified in its charter)

Delaware		001-40223		86-1256660
(State or other jurisdiction  of incorporation)		(Commission File Number)		(I.R.S. Employer  Identification No.)

2261 Market Street, Suite 5447 San Francisco, CA		94114
(Address of principal executive offices)		(Zip Code)

(415) 325-5912

(Registrants telephone number, including area code)

Not Applicable

(Former name or former address, if changed since last report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐	Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)
☐	Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)
☐	Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))
☐	Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each class		Trading Symbol(s)		Name of each exchange on which registered
Common stock, par value $0.0001 per share		BSLK		The Nasdaq Stock Market LLC
Warrants, each 20 whole warrants exercisable for one share of Common stock at an exercise price of $230.00		BSLKW		The Nasdaq Stock Market LLC

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (Sec.230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (Sec.240.12b-2 of this chapter).

Emerging growth company ☒

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Item 5.03 Amendments to Articles of Incorporation or Bylaws; Change in Fiscal Year

On October 17, 2025, the Board of Directors of Bolt Projects Holdings, Inc. (the Company) approved and adopted amendments to the Companys Amended and Restated Bylaws (the Amended and Restated Bylaws), which became effective the same day. Among other things, the amendments contained in the Amended and Restated Bylaws:

● reduce the quorum needed for stockholder meetings to one-third (33.33%) of the Companys voting power of the issued and outstanding shares of capital stock of the Company entitled to vote thereat, present in person or represented by proxy;

● address the universal proxy rules adopted by the U.S. Securities and Exchange Commission, by clarifying that no person may solicit proxies in support of a director nominee other than the Boards nominees unless such person has complied with Rule 14a-19 under the Securities Exchange Act of 1934, as amended, including applicable notice and solicitation requirements;

● establish procedural mechanics and disclosure requirements in connection with stockholder nominations of directors and submissions of proposals regarding other business at stockholder meetings, including, without limitation: requiring certain background information and disclosures regarding proposing stockholders, proposed nominees and business, and other persons related to a stockholders solicitation of proxies; regarding the proposed nominees, including a representation that such candidate intends to serve the entire term, if elected; and prohibiting a stockholder from nominating a greater number of director candidates than are subject to election by stockholders at the applicable meeting;

● require that a stockholder directly or indirectly soliciting proxies from other stockholders use a proxy card color other than white, which will be reserved for exclusive use by the Board;

● update those who may preside at meetings of stockholders and the scope of such persons rights and authority at such meetings; and

● update how vacancies on the Board of Directors may be filled.

The Amended and Restated Bylaws also incorporate certain modernizing, clarifying, conforming and additional changes.

The foregoing description of the Amended and Restated Bylaws does not purport to be complete and is qualified in its entirety by reference to the full text of the Amended and Restated Bylaws, a copy of which is attached hereto as Exhibit 3.1 and is incorporated herein by reference.

Item 9.01 Financial Statements and Exhibits.

(d) Exhibits

Exhibit No.		Description
3.1		Amended and Restated Bylaws, dated as of October 17, 2025.
104		Cover Page Interactive Data File (embedded within the Inline XBRL document).

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SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

	BOLT PROJECTS HOLDINGS, INC.
Date: October 17, 2025	By:	/s/ Daniel Widmaier
	Name:	Daniel Widmaier
	Title:	Chief Executive Officer

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FAQ

What did BSLK file with the SEC?

Bolt Projects filed a Prospectus Supplement No. 2 under Rule 424(b)(3) to update its S-1 by incorporating a recent Form 8-K.

What change did BSLK disclose in the 8-K?

The Board approved and adopted amendments to the Amended and Restated Bylaws, effective October 17, 2025.

Where can I read the amended bylaws?

They are included as Exhibit 3.1 to the Form 8-K and incorporated by reference in the supplement.

What securities are listed for Bolt Projects Holdings (BSLK)?

Common stock (BSLK) and warrants (BSLKW) are listed on The Nasdaq Stock Market LLC.

What registration statement does this supplement relate to?

It relates to the company’s Form S-1, Registration No. 333-289821.

When did the bylaws amendments become effective?

The amendments became effective on October 17, 2025.