Filed Pursuant to Rule 424(b)(3)
Registration No.: 333-292650
PROSPECTUS
ENERGY VAULT HOLDINGS, INC.
Up to 33,251,333 shares of Common Stock Offered by the Selling Stockholder
Issuable Upon Conversion of Obligations Under Convertible Debentures
This prospectus relates to the resale or other disposition from time to time by YA II PN, Ltd. (the “Selling Stockholder”), of up to an aggregate of 33,251,333 shares of common stock, par value $0.0001 per share (“common stock”), of Energy Vault Holdings, Inc. (the “Company,” “we,” “our” or “us”).
On September 22, 2025, we entered into a securities purchase agreement with the Selling Stockholder (the “Purchase Agreement”) pursuant to which we agreed to issue and sell up to $50.0 million in aggregate principal amount of senior unsecured convertible debentures (“Debentures”) to the Selling Stockholder in multiple tranches. The initial $30.0 million tranche (the “First Tranche”) was funded on September 22, 2025 (the “Initial Closing Date”), and an additional $20.0 million tranche (the “Second Tranche”) was funded on December 16, 2025. The First Tranche and the Second Tranche mature on March 22, 2027.
On December 30, 2025, the Company and the Selling Stockholder entered into an amendment to the Purchase Agreement (the “Amendment”), pursuant to which the Company agreed to issue and sell an additional $15.0 million of Debentures to the Selling Stockholder (the “Third Tranche,” collectively with the First Tranche and the Second Tranche, the “Convertible Debentures”). The Third Tranche will mature on August 30, 2027.
Beginning on November 26, 2025, with respect to the First Tranche, and on January 26, 2026, with respect to the Second Tranche and the Third Tranche, and monthly thereafter (each, a “Payment Date”), the Company must satisfy scheduled installments consisting of principal and accrued interest. For each such payment, the Company may (i) pay cash plus a payment premium equal to 7% of the principal portion paid in the case of the First Tranche and the Second Tranche and 4% of the principal portion paid in the case of the Third Tranche (the “Payment Premium”), (ii) elect to allow the Selling Stockholder to convert the unpaid installment at a price equal to the lower of (A) $4.50 per share in the case of the First Tranche, $7.53 per share in the case of the Second Tranche and $7.41 per share in the case of the Third Tranche (the “Fixed Price”) or (B) 97% of the lowest daily volume weighted average price during the four trading days prior to conversion, but which price shall not be lower than $0.60 per share (the “Floor Price”) or (iii) through a combination of cash and conversion.
We are registering these shares of common stock for resale by the Selling Stockholder pursuant to the registration rights granted to the Selling Stockholder under that certain registration rights agreement we entered into with the Selling Stockholder, dated as of September 22, 2025 and as amended and restated on December 30, 2025.
We will not receive any of the proceeds from the sale of common stock by the Selling Stockholder. Pursuant to the Registration Rights Agreement, we will pay certain expenses, other than underwriting discounts and commissions, associated with the sale of common stock by the Selling Stockholder pursuant to this prospectus. Our registration of the common stock covered by this prospectus does not mean that the Selling Stockholder will offer or sell any of the common stock. The Selling Stockholder may offer all or part of the securities for resale from time to time through public or private transactions, at either prevailing market prices or at privately negotiated prices. The Selling Stockholder may sell these securities through ordinary brokerage transactions, directly to market makers of our shares or through any other means described in the section entitled “Plan of Distribution” herein. In connection with any sales of common stock offered hereunder, the Selling Stockholder, any underwriters, agents, brokers or dealers participating in such sales may be deemed to be “underwriters” within the meaning of the Securities Act of 1933, as amended (the “Securities Act”).
This prospectus provides you with a general description of the shares of common stock offered hereby and the general manner in which the Selling Stockholder, upon conversion of obligations under the Convertible Debentures, may offer such securities. More specific terms of any securities that the Selling Stockholder offer may be provided in a prospectus supplement, if required, that describes, among other things, the specific amounts and prices of the securities being offered and the terms of the offering. The prospectus supplement may also add, update or change information contained in this prospectus.
Our headquarters are located at 4165 East Thousand Oaks Blvd., Suite 100, Westlake Village, California 91362. Our common stock is quoted under the symbol “NRGV” on The New York Stock Exchange (“NYSE”). On January 7, 2026, the closing price of our common stock on the NYSE was $5.43 per share. We will provide information in the related prospectus supplement for the trading market, if any, for any other securities that may be offered.
Prior to making a decision about investing in our Securities, you should consider carefully any risk factors contained in a prospectus supplement, as well as the risk factors set forth in our most recently filed Annual Report on Form 10-K and Quarterly Report on Form 10-Q, and other filings we may make from time to time with the Securities and Exchange Commission. See “Risk Factors” on page 5.
We are an “emerging growth company” and a “smaller reporting company” under applicable federal securities laws and therefore subject to reduced public company reporting requirements. See “Our Business — Implications of Being an Emerging Growth Company and a Smaller Reporting Company” herein.
Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or passed upon the accuracy or adequacy of this prospectus. Any representation to the contrary is a criminal offense.
You should read this prospectus and the applicable prospectus supplement for the specific security being offered and any related free writing prospectus carefully before you invest in any of our securities. This prospectus may not be used to consummate sales of securities unless it is accompanied by a prospectus supplement.
THE DATE OF THIS PROSPECTUS IS JANUARY 16, 2026.