Fluence Energy Inc-A美股招股说明书(2026-05-13版)

Class A common stock The selling securityholders identified in this prospectus supplement (the “Selling Securityholders”) are offering 20,000,000sharesof our ClassA common stock. We are not selling any shares of ClassA common stock under this prospectus supplement. The ClassA common stock of Fluence Energy, Inc. is listed on the Nasdaq Global Select Market (“Nasdaq”) under the symbol“FLNC.” On May 11, 2026, the last reported sale price of our ClassA common stock on Nasdaq was $25.23 per share. We have three classes of common stock: ClassA common stock, ClassB-1 common stock and ClassB-2 common stock. Eachshare of our ClassA common stock entitles its holder to one vote per share, each share of our ClassB-1 common stock entitles itsholder to five votes per share and each share of our ClassB-2 common stock entitles its holder to one vote per share on all matterspresented to our stockholders generally. We are a holding company and our principal asset is commonunits of Fluence Energy, LLC (“LLC Interests”). We are the solemanaging member of Fluence Energy, LLC. We operate and control all the business and affairs of Fluence Energy, LLC and its directand indirect subsidiaries and, through Fluence Energy, LLC and its direct and indirect subsidiaries, conduct our business. (1)See “Underwriting” for a description of the compensation payable to the underwriters. The Selling Securityholders have granted the underwriters an option for a period of 30days to purchase up to 3,000,000 additionalshares of ClassA common stock. Investing in our common stock involves a high degree of risk. See the section titled “Risk Factors” beginning on pageS-10of thisprospectus supplement and the other risk factors that we incorporate by reference into this prospectus supplement and the accompanyingprospectus. Neither the Securities and Exchange Commission (the “SEC”) nor any state securities commission has approved or disapproved ofthese securities or passed upon the adequacy or accuracy of this prospectus supplement or the accompanying prospectus. Anyrepresentation to the contrary is a criminal offense. The underwriters expect to deliver the Class A common stock on or about May15, 2026, which will be the second business dayfollowing the initial trade date for the ClassA common stock sold in this offering (this settlement cycle being referred to as “T+2”).Under Rule15c6-1 under the Securities Exchange Act of 1934, as amended, trades in the secondary market generally are required tosettle in one business day, unless the parties to any such trade expressly agree otherwise. Accordingly, purchasers who wish to tradeClassA common stock purchased in this offering prior to the business day preceding the settlement date will be required, by virtue ofthe fact that the shares initially will settle T+2, to specify an alternate settlement cycle at the time of any such trade to prevent a failedsettlement. Purchasers of the Class A common stock who wish to trade such Class A common stock prior to the business day precedingthe settlement date should consult their own advisors. Joint book-running managers Barclays J.P. Morgan MizuhoWells Fargo Securities BNP PARIBASMorgan Stanley The date of this prospectus supplement is May 12, 2026 TABLE OF CONTENTS PagePROSPECTUS SUPPLEMENTABOUT THIS PROSPECTUS SUPPLEMENTS-1CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING INFORMATIONS-2WHERE YOU CAN FIND MORE INFORMATION; INCORPORATION BY REFERENCES-4PROSPECTUS SUPPLEMENT SUMMARYS-6THE OFFERINGS-7RISK FACTORSS-10DIVIDEND POLICYS-16SELLING SECURITYHOLDERSS-17MATERIAL U.S. FEDERAL INCOME TAX CONSEQUENCES TO NON-U.S. HOLDERSS-19UNDERWRITINGS-23LEGAL MATTERSS-34EXPERTSS-35 PROSPECTUS ABOUT THIS PROSPECTUS1CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING INFORMATION2WHERE YOU CAN FIND MORE INFORMATION; INCORPORATION BY REFERENCE4ABOUT FLUENCE ENERGY, INC.6RISK FACTORS7USE OF PROCEEDS8DESCRIPTION OF CAPITAL STOCK9DESCRIPTION OF DEBT SECURITIES15DESCRIPTION OF OTHER SECURITIES22GLOBAL SECURITIES23SELLING SECURITYHOLDERS27PLAN OF DISTRIBUTION29LEGAL MATTERS31EXPERTS31 ABOUT THIS PROSPECTUS SUPPLEMENT This document contains two parts. The first part is this prospectus supplement, which describes thespecific terms of this offering and also supplements and updates information contained in the accompanyingprospectus and the documents incorporated by reference into this prospectus supplement and theaccompanying prospectus. The second part is the accompanying prospectus, which provides more generalinformation, some of which may not apply to this offering. If the information contained in this prospectussupplement differs or varies from the information contained in the accompanying prospectus, you shouldrely on the information set forth in this prospectus supplement. Neither we, nor the Selling Securityholders, have authorized anyone to provide you with anyinformation or to make any representations other than those contained in this prospectus supplement and theaccom