Note 9 — RELATED PARTY TRANSACTIONS

Lease Agreement

The Company had a property lease with a related party which terminated on March 14, 2024. Lease expenses under this lease for the year ended December 31, 2025 and 2024 were $0 and $6,000, respectively, and were included in general and administrative costs in the consolidated statements of operations.

Consultancy Agreement

On January 1, 2019, the Company entered into a consultancy agreement with a company affiliated with the Chief Executive Officer for a monthly payment of $20,000 in exchange for the Chief Executive Officer providing services in connection with the development and sales of Company technologies and products. There was no expense in the consolidated statements of operations for the years ended December 31, 2025 and $80,000 was included in general and administrative expenses in the consolidated statements of operations for the year ended December 31, 2024. On May 1, 2024, this consultancy agreement was terminated. As of December 31, 2025 and 2024, no payments were owed under this agreement.

Office Services Agreement

On October 31, 2020, the Company entered into a consultancy agreement with an affiliate for a monthly payment of $5,000 to provide office services. For the years ended December 31, 2025 and 2024. $0 and $20,000 was included in research and development expenses in the consolidated statements of operations, respectively. On May 1, 2024, this office services agreement was terminated. As of December 31, 2025 and 2024, $0 was owed under this agreement.

Due to Related Party

The Sponsor of XPDB (the “Sponsor”) is a related party as a result of its ownership interest in XPDB prior to the consummation of the Business Combination and its ability to exercise significant influence over XPDB’s operations and strategic decisions through such ownership and board representation.

Commencing on December 9, 2021, and continuing through the consummation of the initial Business Combination, XPDB entered into an administrative services agreement with an affiliate of the Sponsor pursuant to which XPDB agreed to pay $20,000 per month for office space, administrative and support services. The agreement was on a month-to-month basis and did not bear interest. No additional fees were charged beyond the fixed monthly amount. Upon the closing of the Business Combination, the Company assumed the outstanding balance under this arrangement totaling $540,000. The balance was non-interest bearing, unsecured, and was repaid in full in May 2024.

In 2023, in connection with the extension of XPDB’s termination date following stockholder approval of the extension amendment proposal, the Sponsor contributed an aggregate of $900,000 to the XPDB trust account. These contributions were made to fund the required deposits into the trust account in connection with the extension and were evidenced by promissory notes. The promissory notes were non-interest bearing and payable upon the earlier of the consummation of the Business Combination or liquidation of XPDB. Upon the closing of the Business Combination, the Company assumed the outstanding balance of $900,000. The balance was subsequently repaid in full in May 2024.

Due from Related Party

In November 2024, Legacy Montana executed a statement of work with AirJoule, LLC. Expected reimbursement of costs incurred during the year ended December 31, 2025 was $1.6 million and $0.6 million of general and administrative and research and development expenses, respectively, of which $1.0 million was received as of December 31, 2025. Reimbursement of costs incurred as of December 31, 2024 was $2.0 million and $0.8 million of research and development and general and administrative expenses, respectively, of which all was received in 2025.

Related Party Equity Transactions

As described in Note 10 – Stockholders’ Equity (Deficit), Legacy Montana sold equity interests that subsequently converted into shares of Class A common stock, to TEP Montana, LLC (“TEP Montana”). The Executive Chairman of the Company is the managing partner of the managing member of TEP Montana.

The Company granted options and awards to the employees of AirJoule, LLC during the year ended December 31, 2025. The number of options and awards granted to the employees of AirJoule, LLC are found in Note 11 – Stock-based Compensation.