Item 8.01 Other Events. The unaudited pro forma combined balance sheet as of March 31, 2026 (the “ Pro Forma Balance Sheet”), the unaudited pro forma combined statement of operations for the three months ended March 31, 2026 and for the year ended December 31, 2025 (the “ Pro Forma Statements of Operations”), and the notes related thereto (together with the Pro Forma Balance Sheet and the Pro Forma Statements of Operations, the “ Pro Forma Financial Statement s”), are filed as Exhibit 99.1 to this Current Report on Form8-Kand are incorporated by reference into this Item 8.01. The Pro Forma Balance Sheet is presented as if the Merger had been completed on March 31, 2026. The Pro Forma Statements of Operations are presented as if the Merger had been completed on January 1, 2025. The Pro Forma Balance Sheet and the Pro Forma Statements of Operations do not purport to represent what the combined company’s financial position or results of operations would have been if the Merger had actually occurred on the dates indicated, nor are they indicative of Devon’s future financial position or results of operations. Actual results may differ materially from the assumptions and estimates reflected in the Pro Forma Financial Statements.

Item 9.01 Financial Statements and Exhibits. (d) Exhibits. Exhibit Exhibit Name 99.1 Pro Forma Financial Statements. 104 Cover Page Interactive Data File (embedded within the Inline XBRL document). SIGNATURE 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 hereunto duly authorized. DEVON ENERGY CORPORATION By: /s/ Shannon E. Young III Shannon E. Young III Executive Vice President and Chief Financial Officer Date: May 22, 2026