NewHold Investment Corp III (Name of Registrant as Specified In Its Charter) (Form 8-K)

NewHold Investment Corp III
(Name of Registrant as Specified In Its Charter)

(Name of Person(s) Filing Proxy Statement, if other than the Registrant)

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SUPPLEMENT TO PROXY STATEMENT

OF

NewHold Investment Corp III
Dated September 11, 2026

The following disclosures in this proxy supplement (the "Supplement") supplement, and should be read in conjunction with, the disclosures contained in the joint definitive proxy statement/prospectus (the "Proxy Statement"), filed on August 10, 2026, which should be read in its entirety. To the extent the information set forth herein differs from or updates information contained in the Proxy Statement, the information set forth herein shall supersede or supplement the information in the Proxy Statement. All other information in the Proxy Statement remains unchanged.

As provided in the Proxy Statement, NewHold Investment Corp III, a Cayman Islands exempted company (the "SPAC" or "NewHold") is soliciting stockholder approval of, among other things, its proposed business combination (the "Business Combination") with NewCleo Ltd., a private limited company incorporated under the laws of England and Wales (and, following the re-registration to a public limited company under the laws of England and Wales, the "Company" or "Newcleo"), and the other matters as described in the Proxy Statement, which includes a prospectus relating to the offer of the securities to be issued to the stockholders of the Company in connection with the Business Combination. The purpose of the following supplemental disclosures is to provide additional information about the Forward Purchase Agreement (as defined below). Terms used herein, unless otherwise defined, have the meanings set forth in the Proxy Statement.

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DESCRIPTION OF FORWARD PURCHASE AGREEMENT

As previously disclosed, on May 26, 2026, NewHold entered into a Business Combination Agreement (the "Business Combination Agreement") with the Company, newcleo1 Ltd., a Cayman Islands exempted company with limited liability and a direct wholly owned subsidiary of the Company ("Merger Sub 1"), and newcleo2 Ltd., a Cayman Islands exempted company with limited liability and a direct wholly owned subsidiary of the Company ("Merger Sub 2", and, together with Merger Sub 1, the "Merger Subs", and the Merger Subs, together with the Company, the "Company Parties"), pursuant to which, among other transactions, Merger Sub 1 will merge with and into the SPAC, as a result of which the separate corporate existence of Merger Sub 1 will cease and the SPAC will continue as the surviving company in such merger and as a wholly owned subsidiary of the Company (the "First Merger" and the post-First Merger surviving company, the "First Merger Surviving Company"), and First Merger Surviving Company will merge with and into Merger Sub 2, as a result of which the separate corporate existence of First Merger Surviving Company will cease and Merger Sub 2 will continue as the surviving company in such merger and a direct, wholly owned subsidiary of the Company (the "Second Merger" and, together with the First Merger and the other transactions contemplated by the Business Combination Agreement, the "Mergers" or "Business Combination").A copy of the Business Combination Agreement is filed as Exhibit 2.1 to the SPAC's Current Report on Form 8-K filed with the SEC on May 27, 2026.

On September 11, 2026, NewHold and Newcleo entered into an agreement with an unaffiliated stockholder (the "Seller") in connection with a prepaid share forward transaction (the "Forward Purchase Agreement", and such transaction, the "Transaction"). For purposes of the Forward Purchase Agreement, (i) prior to the consummation of the Business Combination, NewHold is referred to as the "Counterparty", and Newcleo is referred to as the "Counterparty" after the consummation of the Business Combination, and (ii) "Shares" means the Class A ordinary shares, par value $0.0001 per share, of NewHold prior to the consummation of the Business Combination, and the ordinary shares, par value $0.02288, of Newcleo after the consummation of the Business Combination. Capitalized terms used herein but not otherwise defined have the meanings ascribed to such terms in the Forward Purchase Agreement.

Pursuant to the terms of the Forward Purchase Agreement, the Seller intends to purchase up to 7,000,000 Shares (the "Recycled Shares") consisting of (i) Shares purchased from third parties in the open market, plus (ii) any Shares held by the Seller at the effective time of the Forward Purchase Agreement. The Seller will irrevocably waive any redemption rights with respect to such Recycled Shares in connection with the Business Combination.

At the closing of the Business Combination, NewHold will pay the Seller a prepayment amount (the "Prepayment Amount") equal to the product of (a) the number of Shares and (b) the per-share redemption price paid to holders of Shares (the "Initial Price") from the trust account of NewHold established in connection with its initial public offering (the "Trust Account"). The Prepayment Amount will be paid directly from the Trust Account no later than the earlier of (a) one Local Business Day after the closing of the Business Combination and (b) the date on which any assets from the Trust Account are disbursed in connection with the Business Combination.

The maturity date (the "Maturity Date") of the Transaction is the earliest to occur of: (a) the date that is 24 months after the closing of the Business Combination, (b) at the option of the Counterparty, any date selected by the Counterparty after the date on which a registration statement covering the resale of Shares issued in the private placement consummated in connection with the Business Combination is declared effective, and (c) a date specified by the Seller in a written notice delivered to the Counterparty at the Seller's sole discretion.

From time to time following the closing of the Business Combination, the Seller may terminate the Transaction in whole or in part by delivering an Optional Early Termination Notice to the Counterparty specifying the number of Shares to be terminated (the "Terminated Shares"). Upon any such Optional Early Termination, the Counterparty will be entitled to receive from the Seller an amount equal to the product of (i) the number of Terminated Shares and (ii) the then-effective Reset Price (the "Reset Price"). The Reset Price will initially be equal to the Initial Price and may only be adjusted downward by mutual written agreement of the parties.

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On the Maturity Date: (i) if the approval of Newcleo's shareholders (as required under the UK Companies Act 2006) to purchase or redeem any Shares pursuant to the Transaction ("Shareholder Approval") has been obtained on or before the Maturity Date, the Transaction shall be physically settled, in which case the Seller shall deliver to the Counterparty the Shares (reduced for any Terminated Shares); the Counterparty shall have no delivery obligation to the Seller; and the Seller shall be entitled to retain a portion of the Prepayment Amount equal to (A) the number of Shares (as reduced for any Terminated Shares) multiplied by (B) the Initial Price; (ii) if Shareholder Approval has not been obtained on or before the Maturity Date, the Transaction shall be settled in cash over a Valuation Period (as defined in the Forward Purchase Agreement) in accordance with the terms of the Forward Purchase Agreement; and (iii) if Shareholder Approval is obtained after the Valuation Period has begun but before it ends, Counterparty may, by written notice to the Seller, suspend and terminate the Valuation Period, and the Transaction shall be physically settled with respect to all Shares then remaining subject to the Transaction, with cash settlement applying only to shares already sold by the Seller.

The Forward Purchase Agreement contains customary representations, warranties and covenants of the parties, including that the Seller will not effect any Short Sales of the Shares or establish or maintain a Net Short Position with respect to the Shares, and that the Seller will waive any and all redemption rights with respect to the Shares acquired pursuant to the Forward Purchase Agreement. The Forward Purchase Agreement also includes customary indemnification provisions in favor of the Seller and its affiliates.

The Forward Purchase Agreement provides that the Transaction has been structured to comply with all tender offer regulations applicable to the Business Combination, including Rule 14e-5 under the Securities Exchange Act of 1934, as amended (the "Exchange Act"). The Seller has agreed to not vote any Shares it holds as of the applicable record date in connection with the Business Combination at any meeting of the Counterparty's shareholders (or to provide a written consent for that purpose with respect to such Shares) if it would be in violation of specified interpretations of the tender offer rules by the SEC. The Seller has also agreed not to purchase Shares at a price per share that is higher than most recently disclosed redemption price per share that would be applicable if the Trust Account was liquidated on the date specified in such disclosure. In addition, the Seller has waived all redemption rights with respect to any previously held Shares or Shares acquired pursuant to the Transaction. The Seller held less than 5% of the Shares prior to the execution of the Forward Purchase Agreement. The purpose of the Transaction is to potentially increase the amount of cash available to the combined company following the Business Combination. Newhold does not believe that the Transaction will impact the likelihood of the Business Combination being approved by shareholders. No redemption requests have been received to date.

In addition to the termination provisions described above, the Forward Purchase Agreement will terminate upon (1) the termination of the Business Combination Agreement prior to the closing of the Business Combination, (2) at the election of the Counterparty, the receipt of certain governmental comments or challenges to the Business Combination Agreement or the Forward Purchase Agreement prior to the closing of the Business Combination, or (3) upon the occurrence of any Material Adverse Change (as defined in the Forward Purchase Agreement) of the Counterparty prior to the closing of the Business Combination (provided that the Counterparty may not elect to terminate the Forward Purchase Agreement due to such Material Adverse Change). Upon any termination due to termination of the Business Combination Agreement or upon the occurrence of a Material Adverse Change, NewHold will be required to promptly redeem a number of Seller's Recycled Shares equal to the lesser of (x) Seller's Recycled Shares, (y) the Number of Shares and (z) 7,000,000 Shares, for aggregate redemption consideration equal to the Initial Price per Share multiplied by the number of such redeemed Shares, less only the Prepayment Amount actually received in respect of such redeemed Shares.

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The foregoing summary of the Forward Purchase Agreement does not purport to be complete and is qualified in its entirety by reference to the full text of the Form of Prepaid Share Forward Confirmation, a copy of which is filed as to the Current Report on Form 8-K filed with the SEC by NewHold on the date hereof.