Rubico Inc美股招股说明书(2026-07-15版)

Up to 50,000,000 Common Shares RUBICO INC. This is a supplement (the “Prospectus Supplement”) to the prospectus, dated May 1, 2026 (as supplemented or amended fromtime to time, the “Prospectus”) of Rubico Inc. (the “Company”), which forms a part of the Company’s Registration Statement on FormF-1 (Registration Nos. 333-295199 and 333-297277), as amended from time to time. This Prospectus Supplement is being filed to update and supplement the information included in the Prospectus with theinformation contained in the Company’s Report on Form 6-K, furnished to the U.S. Securities and Exchange Commission (the“Commission”) on July 15, 2026 (the “Form 6-K”). Accordingly, the Form 6-K is attached to this Prospectus Supplement. This Prospectus Supplement should be read in conjunction with, and delivered with, the Prospectus and is qualified byreference to the Prospectus except to the extent that the information in this Prospectus Supplement supersedes the informationcontained in the Prospectus. This Prospectus Supplement is not complete without, and may not be delivered or utilized except in connection with, theProspectus, including any amendments or supplements to it. Investing in our securities involves a high degree of risk. See “Risk Factors” beginning on page 10 of the Prospectusfor a discussion of information that should be considered in connection with an investment in our securities. Neither the Commission nor any state securities commission has approved or disapproved of these securities ordetermined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense. The date of this prospectus supplement is July 15, 2026. UNITED STATESSECURITIES AND EXCHANGE COMMISSIONWashington, D.C. 20549 FORM 6-K REPORT OF FOREIGN PRIVATE ISSUER PURSUANT TO RULE 13a-16 OR 15d-16 UNDER THE SECURITIESEXCHANGE ACT OF 1934 For the month of July 2026 Commission File Number:001-42684 Rubico Inc.(Translation of registrant's name into English) 20 Iouliou Kaisara Str19002, PaianiaAthens - Greece(Address of principal executive office) Indicate by check mark whether the registrant files or will file annual reports under cover of Form 20-F or Form 40-F.Form 20-F [X ]Form 40-F [] On July 15, 2026, the Registrant issued a press release, a copy of which is attached hereto as Exhibit 99.1 and is incorporated herein byreference. Exhibit 99.1. Press release dated July 15, 2026. The information contained in this Report, except for the commentary of Kalliopi Ornithopoulou contained in Exhibit 99.1, is herebyincorporated by reference into the Registrant’s registration statement on Form F-3 (File No. 333-297207). SIGNATURES Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on itsbehalf by the undersigned, thereunto duly authorized. Rubico Inc.(Registrant)/s/ Nikolaos PapastratisNikolaos PapastratisChief Financial Officer Date: July 15, 2026 Rubico Announces Acquisition of Additional Newbuilding MR Tanker and a 33% Increase of Potential Gross Revenue Backlogto About $305 Million ATHENS, Greece, July 15, 2026 (GLOBE NEWSWIRE) -- Rubico Inc. (Nasdaq: RUBI) (the “Company” or “Rubico”), a globalprovider of shipping transportation services specializing in the ownership of vessels, announced today that it has entered into a sharepurchase agreement (the “SPA”) with Top Ships Inc. to purchase the shares of a company (the “SPV”) that is party to a shipbuildingcontract with Guangzhou Shipyard International Company Limited and China Shipbuilding Trading Co., Ltd. for the construction of a47,499 dwt chemical/product oil carrier (the “Newbuilding MR Tanker”). The Newbuilding MR Tanker is scheduled for delivery in thethird quarter of 2029. The aggregate purchase price for 100% of the shares of the SPV is approximately $6.25 million, payable in full at closing. Thetransaction is expected to close by September 30, 2026, subject to customary closing conditions. The SPV has secured time charter employment for the vessel with a major oil trader, starting from its delivery and for a firm durationof seven years, with charterer’s option to extend for four additional years. The total potential gross revenue backlog from this contract,including optional years, is about $75.4 million. The SPVhasalso entered into a sale and leaseback financing agreement with a major Chinese leasing company for an amount of85%of the installment payments under the shipbuilding contract. The purchase price under the shipbuilding contract, payable ininstallments up to the delivery of the vessel, is $45.2 million out of which $6.8 million has already been paid.Thefinancing bearsaninterest rate ofTerm SOFRplus a margin of1.80%. Under the financing, following the delivery of the vessel,the Companywillpayquarterlyinstallments of $0.5 millionover a period of10years with a balloon payment of $18.2 millionpayable together with the lastinstallment. Top Ships In