Form 8-K

8-K — GRAN TIERRA ENERGY INC.

Accession: 0001104659-26-059507

Filed: 2026-05-12

Period: 2026-05-08

CIK: 0001273441

SIC: 1311 (CRUDE PETROLEUM & NATURAL GAS)

Item: Submission of Matters to a Vote of Security Holders

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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

PURSUANT TO SECTION 13 OR 15(D) OF

THE SECURITIES EXCHANGE ACT OF 1934

Date of Report (Date of earliest event reported):

May 8, 2026

GRAN TIERRA ENERGY INC.

(Exact Name of Registrant as Specified in

its Charter)

Delaware

001-34018

98-0479924

(State or Other Jurisdiction

of Incorporation)

(Commission File Number)

(IRS Employer

Identification No.)

500 Centre Street S.E.

Calgary, Alberta,

Canada

T2G 1A6

(Address of Principal Executive Offices)

(Zip Code)

(403) 265-3221

(Registrant’s Telephone Number, Including

Area Code)

Check

the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any

of the following provisions:

Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title

of each class

Trading

Symbol(s)

Name

of each exchange on which registered

Common Stock, par value $0.001 per share

GTE

NYSE American

Toronto Stock Exchange

London Stock Exchange

Indicate by check mark whether the registrant

is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2

of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company ¨

If an emerging growth company, indicate by check

mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting

standards provided pursuant to Section 13(a) of the Exchange Act. ¨

Item 5.07.

Submission of Matters to a Vote of Security Holders

Gran Tierra Energy Inc. (“Gran Tierra”)

held its 2026 Annual Meeting of Stockholders (the “Annual Meeting”) on May 8, 2026. The following is a brief

description of each matter voted upon at the Annual Meeting, as well as the final tally of (1) the number of votes for, against or abstaining

for each director, (2) the number of votes for, against or abstaining for each other matter, and (3) the number of broker non-votes with

respect to each matter. A more complete description of each matter is set forth in Gran Tierra’s definitive proxy statement filed

with the Securities and Exchange Commission on March 17, 2026 (the “Proxy Statement”).

Proposal 1 - Election of Directors

Gran Tierra’s stockholders duly elected

each of the five nominees proposed by Gran Tierra to serve until Gran Tierra’s 2027 Annual Meeting of Stockholders or until their

respective successor has been duly elected and qualified. The tabulation of votes on this matter was as follows:

Nominee

Shares Voted

For

Shares Voted

Against

Abstaining

Broker

Non-Votes

Gary S. Guidry

12,614,259

5,823,845

61,635

4,310,250

Robert B. Hodgins

12,644,729

5,805,015

49,995

4,310,250

Alison Redford

12,559,307

5,852,219

88,213

4,310,250

Ronald W. Royal

12,498,040

5,932,519

69,180

4,310,250

Brooke Wade

12,558,581

5,857,907

83,251

4,310,250

Proposal 2 - Ratification of Appointment of

Independent Registered Public Accounting Firm

Gran Tierra’s stockholders ratified the

selection of KPMG LLP as Gran Tierra’s independent registered public accounting firm for the fiscal year ending December 31, 2026.

The tabulation of votes on this matter was as follows:

Shares voted for:

17,093,544

Shares voted against:

5,687,961

Shares abstaining:

28,484

Broker non-votes:

Proposal 3 – Advisory Vote to Approve Named Executive Officer

Compensation

Gran Tierra’s stockholders approved, on

an advisory basis, the compensation of Gran Tierra’s named executive officers, as disclosed in the Proxy Statement. The tabulation

of votes on this matter was as follows:

Shares voted for:

12,483,761

Shares voted against:

5,918,465

Shares abstaining:

97,513

Broker non-votes:

4,310,250

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.

Date: May 12, 2026

GRAN TIERRA ENERGY INC.

/s/ Gary S. Guidry

By:

Gary S. Guidry

Title:

President and Chief Executive Officer

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