UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q (Mark One) QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES ☒ EXCHANGE ACT OF 1934 For the quarterly period ended September 30, 2023 or TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES ☐ EXCHANGE ACT OF 1934 For the transition period from __________ to __________ Commission file number 001-34018 GRAN TIERRA ENERGY INC. (Exact name of registrant as specified in its charter) Delaware 98-04799 ...