Soluna Holdings Inc美股招股说明书(2026-05-11版)

2,459,400 Shares of Common Stock This prospectus relates to the resale of 2,459,400 shares of common stock, par value $0.001 per share (the “common stock”),of Soluna Holdings, Inc. (the “Company,” “we,” “our” or “us”) by the selling stockholders listed in this prospectus (the “SellingStockholders”) comprised of (i) 2,400,000 shares of common stock (the “Warrant Shares”) issuable upon the exercise of the warrant(the “Warrant”) issued by the Company to YA II PN, LTD. (“YA”) on April 15, 2026 in connection with that certain SecuritiesPurchase Agreement, dated April 15, 2026, by and between the Company and YA (the “SPA”) and (ii) 59,400 shares of common stock(the “Merger Shares” and together with the Warrant Shares, the “Shares”) issued or issuable to Harmattan Energy, Ltd. (formerlySoluna Technologies, Ltd.) (“HEL”) pursuant to the Merger Agreement (as defined below) in private placement offerings (the “PrivatePlacements”). For additional information about the Private Placements, see “Private Placements.” The Selling Stockholders may, from time to time, sell, transfer or otherwise dispose of any or all of the Shares on any stockexchange, market or trading facility on which the Shares are traded or in private transactions. These dispositions may be at fixedprices, at prevailing market prices at the time of sale, at prices related to the prevailing market price, at varying prices determined atthe time of sale, or at negotiated prices. See “Plan of Distribution” in this prospectus for more information. We will not receive anyproceeds from the resale or other disposition of the Shares by the Selling Stockholders. Our registration of the Shares covered by thisprospectus does not mean that the Selling Stockholders will offer or sell any of the Shares. See “Use of Proceeds” beginning on page10 and “Plan of Distribution” beginning on page 11 of this prospectus for more information. Our common stock is listed on the Nasdaq Capital Market (“Nasdaq”) under the symbol “SLNH”. The last reported sale pricefor our common stock on April 28, 2026 on Nasdaq was $1.08. You should read this prospectus, together with the additional information described under the headings “Incorporation ofCertain Information by Reference” and “Where You Can Find More Information,” carefully before you invest in any of our securities. An investment in our common stock involves a high degree of risk. Before deciding whether to invest in our commonstock, you should consider carefully the risks and uncertainties described in the section captioned “Risk Factors” contained inour Annual Report on Form 10-K for the fiscal year ended December 31, 2025, filed with the Securities and ExchangeCommission, or the SEC, on March 30, 2026 and our other filings we make with the SEC from time to time, which areincorporated by reference herein in their entirety, together with other information in this prospectus and the informationincorporated by reference herein. Neither the SEC nor any state securities commission has approved or disapproved of the shares of common stock ordetermined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense. The date of this prospectus is May 8, 2026. TABLE OF CONTENTS PageABOUT THIS PROSPECTUS1PROSPECTUS SUMMARY2THE OFFERING5PRIVATE PLACEMENTS6RISK FACTORS7CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS8SELLING STOCKHOLDERS9USE OF PROCEEDS10PLAN OF DISTRIBUTION11DESCRIPTION OF CAPITAL STOCK13LEGAL MATTERS16EXPERTS16WHERE YOU CAN FIND MORE INFORMATION16INCORPORATION OF CERTAIN INFORMATION BY REFERENCE17 ABOUT THIS PROSPECTUS This prospectus forms part of a registration statement that we filed with the SEC, and that includes exhibits that provide moredetail with respect to the matters discussed in this prospectus. You should read this prospectus and the related exhibits filed with theSEC, together with the additional information described under the headings “Where You Can Find More Information” and“Incorporation of Certain Information by Reference” before making your investment decision. You should rely only on the information provided in this prospectus or in a prospectus supplement or any free writingprospectuses or amendments thereto. Neither we, nor the Selling Stockholders, have authorized anyone else to provide you withdifferent information. If anyone provides you with different or inconsistent information, you should not rely on it. You should assumethat the information in this prospectus is accurate only as of the date hereof. Our business, financial condition, results of operations andprospects may have changed since that date. Neither we, nor the Selling Stockholders, are offering to sell or seeking offers to purchase the Shares in any jurisdictionwhere the offer or sale is not permitted. We have not done anything that would permit this offering or possession or distribution of thisprospectus in any jurisdiction where action for that purpose is required, other tha