X0202 SCHEDULE 13G 0001257391 XXXXXXXX LIVE Common Stock, par value $0.00001 per share 09/01/2026 0000866829 HORNBECK OFFSHORE SERVICES, INC. 42330P107 103 Northpark Boulevard Suite 300 Covington LA 70433 Rule 13d-1(c) WHITEBOX ADVISORS LLC b DE 0 37873696 0 37873696 37873696 N 15 IA WHITEBOX GENERAL PARTNER LLC b DE 0 37873696 0 37873696 37873696 N 15 OO Whitebox Multi-Strategy Partners, LP b E9 0 19491691 0 19491691 19491691 8.2 PN HORNBECK OFFSHORE SERVICES, INC. 103 Northpark Boulevard, Suite 300, Covington, Louisiana 70433 This statement is filed by: (i) Whitebox Advisors LLC, a Delaware limited liability company ("WA"); (ii) Whitebox General Partner LLC, a Delaware limited liability company ("WGP"); and (iii) Whitebox Multi-Strategy Partners, LP, a Cayman Islands exempted limited partnership ("WMP" and, together with WA and WGP, the "Reporting Persons"). The address of the business office of WA and WGP is: 3033 Excelsior Boulevard Suite 500 Minneapolis, MN 55416 The address of the business office of WMP is: Mourant Governance Services (Cayman) Limited 94 Solaris Avenue, Camana Bay PO Box 1348 Grand Cayman, KY1-1108 Cayman Islands WA and WGP are organized under the laws of the State of Delaware. WMP is organized under the laws of the Cayman Islands. Y As of the date hereof, each of WA and WGP is deemed to be the beneficial owner of 37,873,696 shares of Common Stock, as a result of WA's clients' ownership of (i) 8,239,303 shares of Common Stock and (ii) 29,634,393 shares of Common Stock underlying 2,885,061 warrants, each exercisable to purchase 10.27167 shares of Common Stock at $0.00001 per share (the "Jones Act Warrants"), subject to the Beneficial Ownership Limitation (defined below). As of the date hereof, WMP may be deemed to be the beneficial owner of 19,491,691 shares of Common Stock, as a result of its ownership of (i) 3,002,569 shares of Common Stock and (ii) 16,489,122 shares of Common Stock underlying the Jones Act Warrants, subject to the Beneficial Ownership Limitation. The Jones Act Warrants are subject to certain restrictions on ownership of the Issuer's capital stock by non-U.S. citizens, including a beneficial ownership limitation (the "Beneficial Ownership Limitation") that prevents any holder that cannot establish to the Issuer's reasonable satisfaction that it is a "U.S. Citizen" within the meaning of the U.S. citizenship and cabotage laws commonly referred to as the "Jones Act" (principally 46 U.S.C. Section 50501(a), (b), and (d) and 46 U.S.C. Chapters 121 and 551) from exercising the Jones Act Warrants to the extent that, after giving effect to the issuance of shares of Common Stock upon such exercise, the holder would beneficially own more than 4.9% of the shares of Common Stock outstanding. Based solely on the application of the Beneficial Ownership Limitation to each of WA's clients individually, and based on 222,293,745 shares of Common Stock outstanding as of September 9, 2026, provided by the Issuer, the 2,885,061 Jones Act Warrants held by WA's clients' are currently exercisable for up to an aggregate 21,441,616 shares of Common Stock, including 1,605,301 Jones Act Warrants held by WMP that are currently exercisable for up to 8,296,345 shares of Common Stock. As of the date hereof, each of WA and WGP is deemed to beneficially own approximately 15.0% of the shares of Common Stock outstanding. This percent of class was calculated based on the sum of (i) 222,293,745 shares of Common Stock outstanding as of September 9, 2026, provided by the Issuer, and (ii) 29,634,393 shares of Common Stock that WA and WGP have the right to acquire upon exercise of the Jones Act Warrants, subject to the Beneficial Ownership Limitation, which amount has been added to the shares of Common Stock outstanding in accordance with Rule 13d-3(d)(1)(i) under the Securities Exchange Act of 1934, as amended. As of the date hereof, WMP is deemed to beneficially own approximately 8.2% of the shares of Common Stock outstanding. This percent of class was calculated based on the sum of (i) 222,293,745 shares of Common Stock outstanding as of September 9, 2026, provided by the Issuer, and (ii) 16,489,122 shares of Common Stock that WMP has the right to acquire upon exercise of the Jones Act Warrants, subject to the Beneficial Ownership Limitation, which amount has been added to the shares of Common Stock outstanding in accordance with Rule 13d-3(d)(1)(i) under the Securities Exchange Act of 1934, as amended. Subject to the Beneficial Ownership Limitation, the Jones Act Warrants held by WMP are currently exercisable for up to an aggregate 8,296,345 shares of Common Stock, such that WMP may currently be deemed to beneficially own approximately 4.9% of the shares of Common Stock outstanding. WA and WGP: 0 WMP: 0 WA and WGP: 37,873,696 WMP: 19,491,691 WA and WGP: 0 WMP: 0 WA and WGP: 37,873,696 WMP: 19,491,691 Y N WA's clients, including WMP, are known to have the right to receive or the power to direct the receipt of dividends from, or the proceeds from the sale of, the shares of Common Stock covered by this Statement that may be deemed to be beneficially owned by the Reporting Persons. Y Y Y N By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect, other than activities solely in connection with a nomination under § 240.14a-11. Exhibit A - Joint Filing Agreement, dated September 9, 2026, by and among the Reporting Persons WHITEBOX ADVISORS LLC /s/ Muqu Karim 09/09/2026 WHITEBOX GENERAL PARTNER LLC /s/ Muqu Karim 09/09/2026 Whitebox Multi-Strategy Partners, LP /s/ Muqu Karim 09/09/2026