Form 8-K

8-K — Plum Acquisition Corp, IV

Accession: 0001213900-26-077224

Filed: 2026-07-10

Period: 2026-07-06

CIK: 0002030482

SIC: 6770 (BLANK CHECKS)

Item: Entry into a Material Definitive Agreement

Item: Financial Statements and Exhibits

Documents

8-K — ea0297595-8k425_plum4.htm (Primary)

EX-10.1 — AMENDMENT NO. 2 TO THE BUSINESS COMBINATION AGREEMENT, DATED JULY 6, 2026, BY AND AMONG PLUM ACQUISITION CORP. IV, PLUM IV MERGER SUB INC. AND CONTROLLED THERMAL RESOURCES HOLDINGS INC (ea029759501ex10-1.htm)

XML — IDEA: XBRL DOCUMENT (R1.htm)

8-K — CURRENT REPORT

8-K (Primary)

Filename: ea0297595-8k425_plum4.htm · Sequence: 1

false

0002030482

2026-07-06

0002030482

PLMK:UnitsEachConsistingOfOneClassOrdinaryShareParValue0.0001PerShareAndOnehalfOfOneRedeemableWarrantMember

2026-07-06

0002030482

PLMK:ClassOrdinarySharesParValue0.0001PerShareIncludedAsPartOfUnitsMember

2026-07-06

0002030482

PLMK:WarrantsIncludedAsPartOfUnitsEachWholeWarrantExercisableForOneClassOrdinaryShareAtExercisePriceOf11.50Member

2026-07-06

iso4217:USD

xbrli:shares

iso4217:USD

xbrli:shares

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or Section 15(d) of the

Securities Exchange Act of 1934

Date of Report (Date of earliest event

reported): July 10, 2026 (July 6,

2026)

PLUM ACQUISITION CORP. IV

(Exact name of registrant as specified in its

charter)

Cayman Islands

001-42472

98-1795710

(State or other jurisdiction of

incorporation or organization)

(Commission File Number)

(I.R.S. Employer

Identification Number)

2021 Fillmore St. #2089

San Francisco, California

94115

(Address of principal executive offices)

(Zip Code)

Registrant’s telephone number, including

area code: (929) 529-7125

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 to 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

Units, each consisting of one Class A ordinary share, par value $0.0001 per share, and one-half of one redeemable warrant

PLMKU

Nasdaq Global Market

Class A ordinary shares, par value $0.0001 per share, included as part of the units

PLMK

Nasdaq Global Market

Warrants included as part of the units, each whole warrant exercisable for one Class A ordinary share at an exercise price of $11.50

PLMKW

Nasdaq Global Market

Indicate by check mark whether the registrant

is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 or Rule 12b-2 of the Securities Exchange Act of 1934.

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 1.01. Entry into a Material Definitive Agreement.

As previously disclosed, Plum Acquisition Corp.

IV, a Cayman Islands exempted company (which will transfer by way of continuation from the Cayman Islands to the State of Delaware and

domesticate as a Delaware corporation prior to the closing of the Transactions (as defined below)) (“Plum IV”), Plum

IV Merger Sub, Inc., a Delaware corporation and a direct wholly owned subsidiary of Plum IV (“Merger Sub”), and Controlled

Thermal Resources Holdings Inc., a Delaware corporation (the “Company”) entered into a Business Combination Agreement

(as amended on May 15, 2026, the “Business Combination”), pursuant to which, among other things and subject to the

terms and conditions contained therein, Merger Sub will merge with and into the Company, with the Company continuing as the surviving

company.

On July 6, 2026, Plum IV, the Company and Merger

Sub entered into a second amendment to the Business Combination Agreement (the “Second BCA Amendment” and the Business

Combination Agreement, as amended by the Second BCA Amendment, the “Amended BCA”), which amends the Business

Combination Agreement to, among other things, (i) reduce the aggregate number of potential earnout shares issuable to the Company’s

shareholders following the closing from 100,000,000 to 70,000,000, with each of the eight earnout tranches reduced proportionally from

12,500,000 to 8,750,000 shares; (ii) extend the date by which the parties are required to make any filings or applications required under

antitrust laws with respect to the transactions contemplated by the Amended BCA (the “Transactions”) from July 31,

2026 to September 30, 2026; (iii) increase the maximum number of shares issuable to Plum Partners IV, LLC as reimbursement for founder

shares issued to Plum IV shareholders, or issuable to Plum IV shareholders, who agree not to redeem their Plum IV shares from 2,000,000

to 3,000,000; (iv) extend the date by which the closing must occur from December 31, 2026 to April 30, 2027; (v) reduce the valuation

used to calculate the merger consideration from $4,500,000,000 to $3,150,000,000; and (vi) extend the deadlines by which the Company

is required to deliver certain material consents to the dates listed on Schedule 8.01(m) to the Amended BCA.

The foregoing description of the Second BCA Amendment

does not purport to be complete and is qualified in its entirety by reference to the full text of the Second BCA Amendment, a copy of

which is filed as Exhibit 10.1 to this Current Report on Form 8-K (“Current Report”), and incorporated herein by reference.

Additional Information

and Where to Find It

In connection with the

Transactions, Plum IV and the Company intend to file with the SEC a registration statement on Form S-4 (the “Registration Statement”),

which will include a preliminary proxy statement of Plum IV as well as a preliminary prospectus relating to the offer of securities to

be issued to the stockholders of the Company (the “Proxy Statement/Prospectus”). After the Registration Statement is

declared effective, a definitive proxy statement and other relevant documents will be mailed to shareholders of Plum IV as of the record

date to be established for voting on the Transactions and other matters as described in the Proxy Statement/Prospectus. Plum IV will also

file other documents regarding the Transactions with the SEC. This Current Report does not contain all of the information that should

be considered concerning the Transactions and is not intended to form the basis of any investment decision or any other decision in respect

of the Transactions. BEFORE MAKING ANY VOTING OR INVESTMENT DECISION, SHAREHOLDERS OF PLUM IV AND OTHER INTERESTED PARTIES ARE URGED TO

READ, WHEN AVAILABLE, THE PRELIMINARY PROXY STATEMENT/PROSPECTUS, AND AMENDMENTS THERETO, AND THE DEFINITIVE PROXY STATEMENT/PROSPECTUS

AND ALL OTHER RELEVANT DOCUMENTS FILED OR THAT WILL BE FILED WITH THE SEC IN CONNECTION WITH PLUM IV’S SOLICITATION OF PROXIES FOR

THE EXTRAORDINARY GENERAL MEETING OF ITS SHAREHOLDERS TO BE HELD TO APPROVE THE TRANSACTIONS AND OTHER MATTERS AS DESCRIBED IN THE PROXY

STATEMENT/PROSPECTUS BECAUSE THESE DOCUMENTS WILL CONTAIN IMPORTANT INFORMATION ABOUT PLUM IV, the Company AND THE TRANSACTIONS. Investors

and security holders will also be able to obtain copies of the Registration Statement and the Proxy Statement/Prospectus and all other

documents filed or to be filed with the SEC by Plum IV, without charge, once available, on the SEC’s website at www.sec.gov or by

directing a request to: Plum Acquisition Corp. IV, 2021 Fillmore St., #2089, San Francisco, California 94115, Attention: Kanishka Roy,

or by email at plumir@icrinc.com.

Participants in

the Solicitation

Plum IV, the Company

and their respective directors and executive officers may be deemed participants under SEC rules in the solicitation of proxies from Plum

IV’s shareholders in connection with the Transactions. A list of the names of such directors and executive officers and information

regarding their interests in the Transactions and their ownership of Plum IV’s securities is, or will be, contained in Plum IV’s

filings with the SEC. Additional information regarding the interests of the persons who may, under SEC rules, be deemed participants in

the solicitation of proxies from Plum IV’s shareholders in connection with the Transactions, including the names and interests of

the Company’s directors and executive officers, will be set forth in the Proxy Statement/Prospectus, which is expected to be filed

by Plum IV and the Company with the SEC. Investors and security holders may obtain free copies of these documents as described above.

No Offer or Solicitation

This Current Report is

for informational purposes only and is not a proxy statement or solicitation of a proxy, consent or authorization with respect to any

securities or in respect of the Transactions and shall not constitute an offer to sell or exchange, or a solicitation of an offer to buy

or exchange the securities of Plum IV or the Company, or any commodity or instrument or related derivative, nor shall there be any sale

of any such securities in any state or jurisdiction in which such offer, solicitation, sale or exchange would be unlawful prior to registration

or qualification under the securities laws of any such state or jurisdiction. This Current Report is not, and under no circumstances is

to be construed as, a prospectus, an advertisement or a public offering of the securities described herein in the United States or any

other jurisdiction. No offer of securities shall be made except by means of a prospectus meeting the requirements of the Securities Act

or an exemption therefrom. Investors should consult with their counsel as to the applicable requirements for a purchaser to avail itself

of any exemption under the Securities Act.

Forward-Looking

Statements

This Current Report and

the exhibits attached hereto contain certain forward-looking statements within the meaning of the U.S. federal securities laws with

respect to the Transactions and the parties thereto. All statements contained in this Current Report other than statements of historical

fact, including, without limitation, statements regarding the Transactions between Plum IV and the Company; the anticipated benefits and

timing of the Transactions; expected trading of the combined company’s securities on the Nasdaq; the building of the Company’s

flagship Hell’s Kitchen Project; the anticipated benefits and timing of the Company’s flagship Hell’s Kitchen Project,

the combined company’s future financial performance; the ability of the combined company to execute its business strategy, its market

opportunity and positioning; and other statements regarding management’s intentions, beliefs, or expectations with respect to the

combined company’s future performance, are forward-looking statements.

Forward-looking statements

are often identified by the use of words such as “anticipate,” “believe,” “continue,” “could,”

“estimate,” “expect,” “intend,” “may,” “might,” “plan,” “potential,”

“predict,” “project,” “should,” “will,” “would,” and similar expressions,

but the absence of these words does not mean that a statement is not forward-looking.

These forward-looking

statements are based on the current expectations and assumptions of Plum IV and the Company and are subject to risks and uncertainties

that could cause actual results to differ materially from those expressed or implied by such forward-looking statements. Such risks and

uncertainties include, but are not limited to: (1) the occurrence of any event, change or other circumstances that could give rise to

the termination of the Business Combination Agreement; (2) the outcome of any legal proceedings that may be instituted against the parties

following the announcement of the Transactions and any definitive agreements with respect thereto; (3) the inability to complete the Transactions,

including due to failure to obtain approval of the shareholders of Plum IV and the Company or other conditions to closing; (4) the risk

that the Transactions may not be completed by Plum IV’s business combination deadline and the potential failure to obtain an extension

of the business combination deadline if sought by Plum IV; (5) the inability to maintain the listing of Plum IV’s securities or

to obtain or maintain the listing of the combined company’s securities on the Nasdaq, the New York Stock Exchange, or another national

securities exchange following the Transactions; (6) the risk that the Transactions disrupts the Company’s current plans, business

relationships, performance, operations and business generally as a result of the announcement and consummation of the Transactions; (7)

the risk that the price of the combined company’s securities may be volatile due to a variety of factors, including changes in laws,

regulations, technologies, natural disasters, geopolitical tensions, and macro-economic and social environments affecting its business;

(8) the ability to recognize the anticipated benefits of the Transactions, which may be affected by, among other things, competition,

the ability of the combined company to grow and manage growth profitably and retain its key employees; (9) costs related to the Transactions;

(10) changes in applicable laws or regulations; (11) risks related to the Company’s business, including fluctuations in demand and

prices for lithium and other critical minerals, competition within the industry, the risks inherent in development projects and exploration

activities, potential delays or cost overruns in capital expenditures, the ability to secure necessary raw materials, compliance with

regulatory requirements, environmental and safety obligations, economic and market conditions, and political or geopolitical developments;

and (12) other risks detailed from time to time in Plum IV’s filings with the SEC, including the Registration Statement and related

documents filed or to be filed in connection with the Transactions.

The foregoing list of

risk factors is not exhaustive. You should carefully consider the foregoing factors and the other risks and uncertainties described in

the “Risk Factors” section of Plum IV’s Annual Report on Form 10-K filed with the SEC on March 31, 2026, Plum IV’s

Quarterly Report on Form 10-Q filed with the SEC on May 15, 2026, subsequent Quarterly Reports on Form 10-Q and the Registration Statement

and Proxy Statement/Prospectus that will be filed by Plum IV and the Company, and other documents filed by Plum IV from time to time with

the SEC, as well as the list of risk factors included herein. These filings identify and address other important risks and uncertainties

that could cause actual results to differ materially from those contained in the forward-looking statements. Additional risks and uncertainties

not currently known or that are currently deemed immaterial may also cause actual results to differ materially from those expressed or

implied by such forward-looking statements. Readers are cautioned not to put undue reliance on forward-looking statements, and none of

the parties or any of their representatives assumes any obligation and do not intend to update or revise these forward-looking statements,

each of which is made only as of the date of this Current Report.

Item 9.01. Financial

Statements and Exhibits.

(d) Exhibits.

Exhibit No.

Description

10.1†

Amendment No. 2 to the Business Combination Agreement, dated July 6, 2026, by and among Plum Acquisition Corp. IV, Plum IV Merger Sub Inc. and Controlled Thermal Resources Holdings Inc.

104

Cover Page Interactive Data File (embedded within the Inline XBRL document)

† Certain of the exhibits and schedules to this exhibit have

been omitted in accordance with Regulation S-K Item 601(b)(2). The Registrant agrees to furnish supplementally a copy of all omitted

exhibits and schedules to the SEC upon its request.

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.

Date: July 10, 2026

PLUM ACQUISITION CORP. IV

By:

/s/ Kanishka Roy

Name:

Kanishka Roy

Title:

Chief Executive Officer

EX-10.1 — AMENDMENT NO. 2 TO THE BUSINESS COMBINATION AGREEMENT, DATED JULY 6, 2026, BY AND AMONG PLUM ACQUISITION CORP. IV, PLUM IV MERGER SUB INC. AND CONTROLLED THERMAL RESOURCES HOLDINGS INC

EX-10.1

Filename: ea029759501ex10-1.htm · Sequence: 2

Exhibit 10.1

AMENDMENT NO. 2 TO BUSINESS COMBINATION

AGREEMENT, dated as of July 6, 2026 (this “Amendment”), by and among Plum Acquisition Corp. IV, a Cayman

Islands exempted company (the “Purchaser”), Plum IV Merger Sub Inc., a Delaware corporation and a direct wholly

owned subsidiary of the Purchaser (“Merger Sub”), and Controlled Thermal Resources Holdings Inc., a Delaware

corporation (the “Company” and together with the Purchaser and Merger Sub, the “Parties”).

RECITALS

A. The

Parties entered into a Business Combination Agreement dated as of March 8, 2026 (as amended on May 15, 2026, the “Business Combination

Agreement”).

B. The

Parties wish to enter into this Amendment to make certain amendments to the Business Combination Agreement as set out herein.

AGREEMENT

In consideration of the foregoing and the mutual

covenants and agreements herein contained, the Parties hereby agree as follows:

1.01 Amendments

(a) Section 2.10 of the Business Combination Agreement is deleted in its entirety and replaced with the following:

“2.10 Earnout.

(a) Subject to adjustment pursuant to Section 2.10(f), the holders of Company Common Stock (other than Company Restricted Shares) immediately prior to the Effective Time (such holders, the “Company Shareholders”) shall have the right to receive, in the aggregate, up to 70,000,000 additional shares of Domesticated Purchaser Common Stock (such shares, if and as earned in accordance with this Section, the “Earnout Shares”) during the ten-year period after the Closing Date (the “Earnout Period”) in accordance with this Section and the DGCL.

(b) During the Earnout Period, the Domesticated Purchaser shall issue, and the Company Shareholders shall have the right to receive their respective portion of, the Earnout Shares as follows:

(i) An

aggregate of 8,750,000 Earnout Shares shall be issued if the VWAP for the Domesticated Purchaser Common Stock for any 20 trading days

during any 30 consecutive trading days equals or is greater than $12.50 per share;

(ii) An

aggregate of 8,750,000 Earnout Shares shall be issued if the VWAP for the Domesticated Purchaser Common Stock for any 20 trading days

during any 30 consecutive trading days equals or is greater than $15.00 per share;

(iii) An

aggregate of 8,750,000 Earnout Shares shall be issued if the VWAP for the Domesticated Purchaser Common Stock for any 20 trading days

during any 30 consecutive trading days equals or is greater than $17.50 per share;

(iv) An

aggregate of 8,750,000 Earnout Shares shall be issued if the VWAP for the Domesticated Purchaser Common Stock for any 20 trading days

during any 30 consecutive trading days equals or is greater than $20.00 per share;

(v) An

aggregate of 8,750,000 Earnout Shares shall be issued if the VWAP for the Domesticated Purchaser Common Stock for any 20 trading days

during any 30 consecutive trading days equals or is greater than $22.50 per share;

(vi) An

aggregate of 8,750,000 Earnout Shares shall be issued if the VWAP for the Domesticated Purchaser Common Stock for any 20 trading days

during any 30 consecutive trading days equals or is greater than $25.00 per share;

(vii) An

aggregate of 8,750,000 Earnout Shares shall be issued if the VWAP for the Domesticated Purchaser Common Stock for any 20 trading days

during any 30 consecutive trading days equals or is greater than $27.50 per share; and

(viii) An

aggregate of 8,750,000 Earnout Shares shall be issued if the VWAP for the Domesticated Purchaser Common Stock for any 20 trading

days during any 30 consecutive trading days equals or is greater than $30.00 per share (each such condition, a “VWAP

Condition”).

the avoidance of doubt, each time a VWAP Condition is met, all lower VWAP Conditions not previously met are deemed met and the correlated

Earnout Shares are deemed earned and owing hereunder. By way of illustration, if the VWAP for a given 20 trading days in a 30 consecutive

trading period during the Earnout Period equals $17.50, an aggregate of 26,250,000 Earnout Shares would be earned (if not already previously

earned) as of such measurement date (i.e., 8,750,000 for each of the three VWAP Conditions met).

(d) Notwithstanding the

foregoing or any other provision of this Agreement, to the extent there is a COC Event prior to any VWAP Condition being met, all

Earnout Shares not yet issued will be immediately due and owing upon such COC Event regardless of the number of Earnout Shares that

would otherwise have been earned based on any VWAP Condition should a COC Event not have occurred. For purpose of this Section, a

“COC Event” means the occurrence of any of the following (or any series of the following) with respect to the

Purchaser or the Surviving Company: (i) the direct or indirect sale or exchange in a single or series of related transactions by the

stockholders of such Person of more than fifty percent (50%) of the voting stock of such Person; (ii) a merger or consolidation in

which such Person is a party; (iii) the sale, exchange, or transfer of all or substantially all of the assets of such Person; or

(iv) a liquidation or dissolution of such Person; or

(v) any other event wherein ownership

of shares of such Person of more than fifty percent (50%) of the total combined voting power of the outstanding voting securities of such

Person were transferred.

(e) Issuances

of Earnout Shares, if any, shall be made promptly (and in any event no later than the tenth Business Day) following satisfaction of a

VWAP Condition. The Purchaser shall, or shall cause its transfer agent to, provide evidence of such issuance to each Company Shareholder

promptly thereafter.

(f) The

applicable number of Earnout Shares issued (including for each VWAP Condition met), if any, shall be subject to equitable adjustment for

share splits, share dividends, reorganizations, combinations, recapitalizations and similar transactions affecting the Purchaser after

the Closing.”

(b) Section 6.09(b) of the Business Combination Agreement is deleted in its entirety and replaced with the following:

“(b) In furtherance and

not in limitation of Section 6.09(a), to the extent required under the HSR Act any other Laws that are designed to prohibit,

restrict or regulate actions having the purpose or effect of monopolization or restraint of trade or lessening of competition

through merger or acquisition (collectively, “Antitrust Laws”), each Party hereto agrees to make any required

filing or application under Antitrust Laws, as applicable, at such Party’s sole cost and expense (except that any fees or

other amounts charged by any Governmental Authorities relating to such filings or applications by the Company or the Purchaser under

Antitrust Laws will be paid by the Company and borne 50% by the Company as a Company Transaction Cost and 50% by the Purchaser as a

Purchaser Transaction Cost), with respect to the Transactions as promptly as practicable (but in no event later than September 30,

2026, except as mutually agreed otherwise by the Parties), to supply as promptly as reasonably practicable any additional

information and documentary material that may be requested pursuant to Antitrust Laws and to take all other actions reasonably

necessary, proper or advisable to cause the expiration or termination of the applicable waiting periods under Antitrust Laws as soon

as practicable, including by requesting early termination of the waiting period provided for under the HSR Act or any other

Antitrust Laws and obtaining any approval required under any other Antitrust Laws; provided, that neither Party shall extend

any waiting period under the HSR Act or comparable period under any other Antitrust Laws or enter into any agreement with any

Governmental Authority to so extend such waiting period or comparable period without the prior written consent of the other Parties.

Each Party shall, in connection with its efforts to obtain all requisite approvals and authorizations for the Transactions under any

Antitrust Law, use its reasonable best efforts to: (i) cooperate in all respects with each other Party or its Affiliates in

connection with any filing or submission and in connection with any investigation or other inquiry, including any proceeding

initiated by a private Person; (ii) keep the other Parties reasonably informed of any material communication received by such Party

or its Representatives from, or given by such Party or its Representatives to, any Governmental Authority and of any communication

received or given in connection with any proceeding by a private Person, in each case regarding any of the Transactions; (iii)

permit a Representative of the other Parties and their respective outside counsel to review any material communication given by it

to, and consult with each other in advance of any meeting or conference with, any Governmental Authority or, in connection with any

proceeding by a private Person, with any other Person, and unless prohibited by such Governmental Authority or other Person, give a

Representative or Representatives of the other Parties the opportunity to attend and participate in such meetings and conferences;

(iv) in the event a Party’s Representative is prohibited from participating in or attending any meetings or conferences, the

other Parties shall keep such Party promptly and reasonably apprised with respect thereto; and (v) use reasonable best efforts to

cooperate in the filing of any memoranda, white papers, filings, correspondence or other written communications explaining or

defending the Transactions, articulating any regulatory or competitive argument, and/or responding to requests or objections made by

any Governmental Authority. The Parties agree that any written materials of such Party (including without limitation any

notification and report forms filed under the HSR Act concerning the Transactions) may be redacted or disclosed for outside counsel

only, as necessary to comply with contractual arrangements and as necessary to address reasonable privilege or confidentiality

concerns, in each event prior to sharing such materials with another Party.”

“Issuance to

Non-Redeeming Holders. The Company agrees that, in connection with the Closing, Purchaser shall issue an aggregate of up to

3,000,000 shares of Domesticated Purchaser Common Stock (such shares, the “Non-Redemption Shares”) to certain

Purchaser Shareholders (each, a “Non-Redeeming Holder”) (or to Sponsor, as reimbursement for Founder Shares

issued to Non-Redeeming Holders) who, in connection with any shareholder meetings of Purchaser, enter into non-redemption agreements

(each, a “Non-Redemption Agreement”) with Purchaser and/or Sponsor pursuant to which such Non-Redeeming Holder

agrees to (a) not exercise their Redemption rights with respect to any Purchaser Class A Ordinary Shares beneficially owned by such

Non-Redeeming Holder on the date of such Non-Redemption Agreement and (b) not sell, encumber or otherwise transfer such Purchaser

Class A Ordinary Shares. For the avoidance of doubt, the Non-Redemption Shares shall be in addition to (and not part of) the

Aggregate Merger Consideration.”

(d) Section 8.01(d) of the Business Combination Agreement is deleted in its entirely and replaced with

the following:

“(d) by written notice by the

Purchaser or the Company if any of the conditions to the Closing set forth in Article VII have not been satisfied or waived by April 30,

2027 (the “Outside Date”); provided, however, the right to terminate this Agreement under this Section 8.01(d) shall

not be available to a Party if the breach or violation by such Party or its Affiliates of any representation, warranty, covenant or obligation

under this Agreement was the cause of, or resulted in, the failure of the Closing to occur on or before the Outside Date.”

(e) The definition of “Public Company (Per-Capital Raise) Valuation”

under Section 10.01 of the Business Combination Agreement is deleted in its entirety

and replaced with the following:

““Public Company (Pre-Capital

Raise) Valuation” means $3,150,000,000 (Three Billion One Hundred and Fifty Million United States Dollars).”

(f) Schedule 8.01(m) attached to the Business Combination Agreement is deleted in its entirety and

replaced with Schedule 8.01(m) attached as Schedule 1 hereto.

1.02 General Provisions

(a) Any references to “this Agreement” in the Business Combination Agreement will mean the Business

Combination Agreement as modified by this Amendment. Except as specifically amended by this Amendment, the provisions of the Business

Combination Agreement shall remain in full force and effect.

(b) This Amendment, the Business Combination Agreement (as modified by this Amendment) and the Ancillary Documents

constitute the entire understanding of the Parties and supersedes all prior agreements, undertakings, arrangements, promises and commitments,

whether written or oral, express or implied, relating to the subject matter hereof, and all such prior agreements, understandings, arrangements,

promises and commitments are hereby canceled and terminated.

shall be incorporated, mutatis mutandis, by reference into this Amendment and shall form an integral part of this Amendment.

[Signature Page Follows.]

The Purchaser, Merger Sub and the Company have

caused this Amendment to be executed as of the date first written above by their respective officers thereunto duly authorized.

PLUM ACQUISITION CORP. IV

By:

/s/ Kanishka Roy

Name:

Kanishka Roy

Title:

Chief Executive Officer

PLUM IV MERGER SUB INC.

By:

/s/ Kanishka Roy

Name:

Kanishka Roy

Title:

President

CONTROLLED THERMAL RESOURCES HOLDINGS INC.

By:

/s/ James Turner

Name:

James Turner

Title:

President

XML — IDEA: XBRL DOCUMENT

XML

Filename: R1.htm · Sequence: 8

v3.26.1

Cover

Jul. 06, 2026

Document Type

8-K

Amendment Flag

false

Document Period End Date

Jul. 06, 2026

Entity File Number

001-42472

Entity Registrant Name

PLUM ACQUISITION CORP. IV

Entity Central Index Key

0002030482

Entity Tax Identification Number

98-1795710

Entity Incorporation, State or Country Code

Entity Address, Address Line One

2021 Fillmore St. #2089

Entity Address, City or Town

San Francisco

Entity Address, State or Province

Entity Address, Postal Zip Code

94115

City Area Code

929

Local Phone Number

529-7125

Written Communications

true

Soliciting Material

false

Pre-commencement Tender Offer

false

Pre-commencement Issuer Tender Offer

false

Entity Emerging Growth Company

true

Elected Not To Use the Extended Transition Period

false

Units, each consisting of one Class A ordinary share, par value $0.0001 per share, and one-half of one redeemable warrant

Title of 12(b) Security

Units, each consisting of one Class A ordinary share, par value $0.0001 per share, and one-half of one redeemable warrant

Trading Symbol

PLMKU

Security Exchange Name

NASDAQ

Class A ordinary shares, par value $0.0001 per share, included as part of the units

Title of 12(b) Security

Class A ordinary shares, par value $0.0001 per share, included as part of the units

Trading Symbol

PLMK

Security Exchange Name

NASDAQ

Warrants included as part of the units, each whole warrant exercisable for one Class A ordinary share at an exercise price of $11.50

Title of 12(b) Security

Warrants included as part of the units, each whole warrant exercisable for one Class A ordinary share at an exercise price of $11.50

Trading Symbol

PLMKW

Security Exchange Name

NASDAQ

- Definition

Boolean flag that is true when the XBRL content amends previously-filed or accepted submission.

+ References

No definition available.

+ Details

Name:

dei_AmendmentFlag

Namespace Prefix:

dei_

Data Type:

xbrli:booleanItemType

Balance Type:

Period Type:

duration

- Definition

Area code of city

+ References

No definition available.

+ Details

Name:

dei_CityAreaCode

Namespace Prefix:

dei_

Data Type:

xbrli:normalizedStringItemType

Balance Type:

Period Type:

duration

- Definition

For the EDGAR submission types of Form 8-K: the date of the report, the date of the earliest event reported; for the EDGAR submission types of Form N-1A: the filing date; for all other submission types: the end of the reporting or transition period. The format of the date is YYYY-MM-DD.

+ References

No definition available.

+ Details

Name:

dei_DocumentPeriodEndDate

Namespace Prefix:

dei_

Data Type:

xbrli:dateItemType

Balance Type:

Period Type:

duration

- Definition

The type of document being provided (such as 10-K, 10-Q, 485BPOS, etc). The document type is limited to the same value as the supporting SEC submission type, or the word 'Other'.

+ References

No definition available.

+ Details

Name:

dei_DocumentType

Namespace Prefix:

dei_

Data Type:

dei:submissionTypeItemType

Balance Type:

Period Type:

duration

- Definition

Address Line 1 such as Attn, Building Name, Street Name

+ References

No definition available.

+ Details

Name:

dei_EntityAddressAddressLine1

Namespace Prefix:

dei_

Data Type:

xbrli:normalizedStringItemType

Balance Type:

Period Type:

duration

- Definition

Name of the City or Town

+ References

No definition available.

+ Details

Name:

dei_EntityAddressCityOrTown

Namespace Prefix:

dei_

Data Type:

xbrli:normalizedStringItemType

Balance Type:

Period Type:

duration

- Definition

Code for the postal or zip code

+ References

No definition available.

+ Details

Name:

dei_EntityAddressPostalZipCode

Namespace Prefix:

dei_

Data Type:

xbrli:normalizedStringItemType

Balance Type:

Period Type:

duration

- Definition

Name of the state or province.

+ References

No definition available.

+ Details

Name:

dei_EntityAddressStateOrProvince

Namespace Prefix:

dei_

Data Type:

dei:stateOrProvinceItemType

Balance Type:

Period Type:

duration

- Definition

A unique 10-digit SEC-issued value to identify entities that have filed disclosures with the SEC. It is commonly abbreviated as CIK.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Exchange Act

-Number 240

-Section 12

-Subsection b-2

+ Details

Name:

dei_EntityCentralIndexKey

Namespace Prefix:

dei_

Data Type:

dei:centralIndexKeyItemType

Balance Type:

Period Type:

duration

- Definition

Indicate if registrant meets the emerging growth company criteria.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Exchange Act

-Number 240

-Section 12

-Subsection b-2

+ Details

Name:

dei_EntityEmergingGrowthCompany

Namespace Prefix:

dei_

Data Type:

xbrli:booleanItemType

Balance Type:

Period Type:

duration

- Definition

Indicate if an emerging growth company has elected not to use the extended transition period for complying with any new or revised financial accounting standards.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Securities Act

-Number 7A

-Section B

-Subsection 2

+ Details

Name:

dei_EntityExTransitionPeriod

Namespace Prefix:

dei_

Data Type:

xbrli:booleanItemType

Balance Type:

Period Type:

duration

- Definition

Commission file number. The field allows up to 17 characters. The prefix may contain 1-3 digits, the sequence number may contain 1-8 digits, the optional suffix may contain 1-4 characters, and the fields are separated with a hyphen.

+ References

No definition available.

+ Details

Name:

dei_EntityFileNumber

Namespace Prefix:

dei_

Data Type:

dei:fileNumberItemType

Balance Type:

Period Type:

duration

- Definition

Two-character EDGAR code representing the state or country of incorporation.

+ References

No definition available.

+ Details

Name:

dei_EntityIncorporationStateCountryCode

Namespace Prefix:

dei_

Data Type:

dei:edgarStateCountryItemType

Balance Type:

Period Type:

duration

- Definition

The exact name of the entity filing the report as specified in its charter, which is required by forms filed with the SEC.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Exchange Act

-Number 240

-Section 12

-Subsection b-2

+ Details

Name:

dei_EntityRegistrantName

Namespace Prefix:

dei_

Data Type:

xbrli:normalizedStringItemType

Balance Type:

Period Type:

duration

- Definition

The Tax Identification Number (TIN), also known as an Employer Identification Number (EIN), is a unique 9-digit value assigned by the IRS.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Exchange Act

-Number 240

-Section 12

-Subsection b-2

+ Details

Name:

dei_EntityTaxIdentificationNumber

Namespace Prefix:

dei_

Data Type:

dei:employerIdItemType

Balance Type:

Period Type:

duration

- Definition

Local phone number for entity.

+ References

No definition available.

+ Details

Name:

dei_LocalPhoneNumber

Namespace Prefix:

dei_

Data Type:

xbrli:normalizedStringItemType

Balance Type:

Period Type:

duration

- Definition

Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Exchange Act

-Number 240

-Section 13e

-Subsection 4c

+ Details

Name:

dei_PreCommencementIssuerTenderOffer

Namespace Prefix:

dei_

Data Type:

xbrli:booleanItemType

Balance Type:

Period Type:

duration

- Definition

Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Exchange Act

-Number 240

-Section 14d

-Subsection 2b

+ Details

Name:

dei_PreCommencementTenderOffer

Namespace Prefix:

dei_

Data Type:

xbrli:booleanItemType

Balance Type:

Period Type:

duration

- Definition

Title of a 12(b) registered security.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Exchange Act

-Number 240

-Section 12

-Subsection b

+ Details

Name:

dei_Security12bTitle

Namespace Prefix:

dei_

Data Type:

dei:securityTitleItemType

Balance Type:

Period Type:

duration

- Definition

Name of the Exchange on which a security is registered.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Exchange Act

-Number 240

-Section 12

-Subsection d1-1

+ Details

Name:

dei_SecurityExchangeName

Namespace Prefix:

dei_

Data Type:

dei:edgarExchangeCodeItemType

Balance Type:

Period Type:

duration

- Definition

Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as soliciting material pursuant to Rule 14a-12 under the Exchange Act.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Exchange Act

-Number 240

-Section 14a

-Subsection 12

+ Details

Name:

dei_SolicitingMaterial

Namespace Prefix:

dei_

Data Type:

xbrli:booleanItemType

Balance Type:

Period Type:

duration

- Definition

Trading symbol of an instrument as listed on an exchange.

+ References

No definition available.

+ Details

Name:

dei_TradingSymbol

Namespace Prefix:

dei_

Data Type:

dei:tradingSymbolItemType

Balance Type:

Period Type:

duration

- Definition

Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as written communications pursuant to Rule 425 under the Securities Act.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Securities Act

-Number 230

-Section 425

+ Details

Name:

dei_WrittenCommunications

Namespace Prefix:

dei_

Data Type:

xbrli:booleanItemType

Balance Type:

Period Type:

duration

- Details

Name:

us-gaap_StatementClassOfStockAxis=PLMK_UnitsEachConsistingOfOneClassOrdinaryShareParValue0.0001PerShareAndOnehalfOfOneRedeemableWarrantMember

Namespace Prefix:

Data Type:

Balance Type:

Period Type:

- Details

Name:

us-gaap_StatementClassOfStockAxis=PLMK_ClassOrdinarySharesParValue0.0001PerShareIncludedAsPartOfUnitsMember

Namespace Prefix:

Data Type:

Balance Type:

Period Type:

- Details

Name:

us-gaap_StatementClassOfStockAxis=PLMK_WarrantsIncludedAsPartOfUnitsEachWholeWarrantExercisableForOneClassOrdinaryShareAtExercisePriceOf11.50Member

Namespace Prefix:

Data Type:

Balance Type:

Period Type: