UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

FORM 6-K

REPORT OF FOREIGN PRIVATE ISSUER PURSUANT TO RULE 13a-16 OR
15d-16 UNDER THE SECURITIES EXCHANGE ACT OF 1934

For the month of December 2025

Commission File Number: 001-42684

RUBICO INC.
(Translation of registrant’s name into English)

20 Iouliou Kaisara Str

19002 Paiania

Athens, 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 ☒ Form 40-F ☐

Information Contained in this Form 6-K Report

Attached to this report on Form 6-K as Exhibit 99.1 are the proxy materials for the 2026 Annual Meeting of Shareholders of Rubico Inc. (the “Corporation”).

Attached to this report on Form 6-K as Exhibit 99.2 is the proxy card for the 2026 Annual Meeting of Shareholders of the Corporation.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.


	RUBICO INC.
	(Registrant)

	By:	/s/ Kalliopi Ornithopoulou
	Name:	Kalliopi Ornithopoulou
	Title:	Chief Executive Officer

Date: December 29, 2025

Rubico Inc. 6-K