Rubico Inc美股招股说明书(2026-07-16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 16, 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 16, 2026. UNITED STATESSECURITIES AND EXCHANGE COMMISSIONWashington, D.C. 20549FORM 6-KREPORT OF FOREIGN PRIVATE ISSUER PURSUANT TO RULE 13a-16 OR 15d-16 UNDER THE SECURITIESEXCHANGE ACT OF 1934For the month of July 2026Commission File Number:001-42684Rubico 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 16, 2026, the Registrant issued a press release, a copy of which is attached hereto as Exhibit 99.1 and is incorporatedherein by reference. Exhibit 99.1. Press release dated July 16, 2026. The information contained in this Report, except for the commentary of Kalliopi Ornithopoulou contained in Exhibit 99.1, ishereby incorporated 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 16, 2026 Rubico Announces Management Estimate of Net Asset Value to $183.1 Million, a 94% Increase from the Previously ReportedNAV ATHENS, Greece, July 16, 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 after taking into account theJune 30, 2026, charter free vessel value estimates from third party international brokers, debt outstanding and cash, managementestimates the Company’s net asset value (“NAV”) as of June 30, 2026, to be $183.1 million. This reflects a 94% increase from theprevious NAV reported on March 2, 2026. This translates into a NAV of $300.26 per common share (based on number of commonshares currently outstanding) and $72.22 per common share on a fully diluted basis (assuming exercise of all the 669,193 outstandingwarrants and the conversion of all the Series G Convertible Preferred Shares). The Company’s CEO said: “As of yesterday’s market close, we are trading at a 95% discount to our current estimate of our fully-diluted NAV. Our fleet has anaverage age of approximately 5.2 years, consisting of state-of-the-art vessels equipped with the latest eco-friendly and fuel-efficientspecifications. In addition, our newbuilding pipeline comprises of two high-specification 47,499 dwt MR tanker newbuildings,scheduled for delivery in the third and fourth quarters of 2029, one of which will be acquired through a share purchase agreementexpected to close by September 30, 2026. The pipeline also includes a high-specification 60-meter megayacht scheduled for deliveryin the second quarter of 2027, which we intend to divest to achieve a meaningful equity release — a multiple of our current marketcapitalization, as previously announced.” About the Company Rubico Inc. is a global provider of shipping transportation services specializing in the ownership and operation of tanker vessels. TheCompany is an international owner and operator of two mod