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): July 15, 2025

Plum Acquisition Corp. III

(Exact name of registrant as specified in its charter)

2021 Fillmore St. #2089

San Francisco, CA 94115

(Address of principal executive offices, including Zip Code)

(929) 529-7125

Registrant’s telephone number, including area code

(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:

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

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§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 Certificate of Incorporation or Bylaws; Change in Fiscal Year.

As approved by its shareholders at the extraordinary general meeting of shareholders held on July 15, 2025 (the “Meeting”), Plum Acquisition Corp. III (the “Company”) filed an amendment to its Third Amended and Restated Memorandum and Articles of Association (as amended, the “A&R Charter”) on July 16, 2025, which extended the date by which the Company has to consummate a business combination to July 30, 2026, or such earlier date as shall be determined by the Company’s board of directors (the “Extension Proposal”).

The foregoing description of the A&R Charter is qualified in its entirety by the full text, which is filed as Exhibit 3.1 hereto and incorporated herein by reference.

Item 5.07 Submission of Matters to a Vote of Security Holders.

On July 15, 2025, the Company held the Meeting to approve the Extension Proposal and to adjourn the Meeting if necessary to solicit additional votes for the Extension Proposal, which proposals are more fully described in the definitive proxy statement filed by the Company with the Securities and Exchange Commission on June 24, 2025. Holders of 7,930,156 ordinary shares of the Company were present in person or by proxy at the meeting, representing approximately 98.15% of the voting power of the Company’s ordinary shares as of the record date and constituting a quorum for the transaction of business.

The voting results for the proposals are set forth below.

Proposal No. 1 - Extension Amendment Proposal. The proposal was approved by the following vote:

Proposal No. 2 - Adjournment Proposal. As there were sufficient votes to approve the Extension Proposal at the Meeting, the adjournment proposal was not presented to shareholders.

Item 9.01 Financial Statements and Exhibits.

(d) Exhibits

SIGNATURES

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 thereunto duly authorized.

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