The Company leases its office in Houston, Texas and its office and demonstration plant in Hillsborough, New Jersey. The Company's lease for its office in Houston is through February 2027. During the three months ended March 31, 2026, the Company extended its lease for its office and demonstration plant in Hillsborough, New Jersey through April 30, 2027. See Note 1 for further information.

For the three months ended March 31, 2026 and 2025, the Company determined that the rent portion of such leases qualified as an operating lease under ASC 842.


(in thousands)	Statements of Operations	Three Months Ended March 31,
Lease Cost	Classification	2026		2025
Operating lease cost	General and administrative expense	$	108	$	94
Variable lease cost	General and administrative expense	48		48
Total operating lease cost		$	156	$	142

For the three months ended March 31, 2026 and 2025, supplemental information related to the Company’s operating lease arrangements are as follows:


(in thousands)	Three Months Ended March 31,
Operating lease – supplemental information	2026			2025
ROU assets obtained in exchange for operating lease	$	365		$	309
Weighted average remaining lease term – operating leases	1.1 years			1.3 years
Discount rate – operating leases	7.50		%	7.50		%

On February 27, 2026, Five Star Clean Fuels filed an original petition against the Company seeking a declaratory judgment that a letter agreement between a subsidiary of the Company and a predecessor of Five Star Clean Fuels constituted a binding contract that effectuates a grant to Five Star Clean Fuels of certain non-exclusive rights to utilize the STG+® technology. The petition primarily seeks non-monetary relief other than court costs and attorney fees. The Company intends to defend its position against the claim. At this time, the Company is unable to reasonably estimate a possible financial loss or range of financial loss, if any, that may be incurred to resolve this matter.