Montauk Renewables, Inc.

NOTE 1—DESCRIPTION OF BUSINESS

Operations and organization

Montauk Renewables’ Business

Montauk Renewables, Inc. (the “Company” or “Montauk Renewables”) is a renewable energy company specializing in the management, recovery and conversion of biogas into Renewable Natural Gas (“RNG”). The Company captures methane, preventing it from being released into the atmosphere, and converts it into either RNG or electrical power for the electrical grid (“Renewable Electricity”). The Company, headquartered in Pittsburgh, Pennsylvania, has more than 30 years of experience in the development, operation and management of landfill methane-fueled renewable energy projects. The Company has current operations at 13 operating projects located in California, Idaho, Ohio, Oklahoma, Pennsylvania, North Carolina and Texas. The Company sells RNG and Renewable Electricity, taking advantage of Environmental Attribute premiums available under federal and state policies that incentivize their use.

Two of the Company’s key revenue drivers are sales of captured gas and sales of Renewable Identification Numbers (“RINs”) to fuel blenders. The Renewable Fuel Standard (“RFS”) is an Environmental Protection Agency (“EPA”) administered federal law that requires transportation fuel to contain a minimum volume of renewable fuel. RNG derived from landfill methane, agricultural digesters and wastewater treatment facilities used as a vehicle fuel qualifies as a D3 (cellulosic biofuel with a 60% greenhouse gas reduction requirement) RIN. The RINs are compliance units for fuel blenders that were created by the RFS program in order to reduce greenhouse gases and imported petroleum into the United States.

An additional program utilized by the Company is the Low Carbon Fuel Standard (“LCFS”). This is state specific and is designed to stimulate the use of low-carbon fuels. To the extent that RNG from the Company’s facilities is used as a transportation fuel in states that have adopted an LCFS program, it is eligible to receive an Environmental Attribute additional to the RIN value under the federal RFS.

Another key revenue driver is the sale of captured electricity and the associated environmental premiums related to renewable sales. The Company’s electric facilities are designed to conform to and monetize various state renewable portfolio standards requiring a percentage of the electricity produced in that state to come from a renewable resource. Such premiums are in the form of Renewable Energy Credits (“RECs”). The Company’s largest electric facility, located in California, receives revenue for the monetization of RECs as a part of a purchase power agreement.

Collectively, the Company benefits from federal and state government incentives in the United States, provided in the form of RINs, RECs, LCFS credits, tax credits and other incentives to end users, distributors, system integrators and manufacturers of renewable energy projects, that promote the use of renewable energy, as Environmental Attributes.

Background and Reorganization Transactions

On January 4, 2021, the Company, Montauk Holdings Limited (“MNK”) and Montauk Holdings USA, LLC (a direct wholly-owned subsidiary of MNK at the time, “Montauk USA”) entered into a series of transactions, including an equity exchange and a distribution collectively referred to as the “Reorganization Transactions,” that resulted in the Company owning all of the assets and entities (other than Montauk USA) previously owned by Montauk USA, and Montauk Renewables became a direct wholly-owned subsidiary of MNK. Prior to the Reorganization Transactions, MNK’s business and operations were conducted entirely through Montauk USA and its U.S. subsidiaries, and MNK held no substantial assets other than equity of Montauk USA. The Company had no significant operations or assets prior to January 4, 2021 when it engaged in the equity exchange with Montauk USA and MNK.

After completion of the Reorganization Transactions, (i) Montauk USA ceased to own any substantial assets and (ii) all entities through which MNK’s business and operations were conducted became owned, directly or indirectly, by the Company. MNK adopted a plan contemporaneously with the completion of the Reorganization Transactions that authorized the liquidation and dissolution of MNK.

On January 15, 2021, MNK sold the membership interest of Montauk USA to a third party. On January 26, 2021, MNK distributed all of the outstanding shares of the Company’s common stock as a pro rata dividend to the holders of MNK’s ordinary shares (the “Distribution”), subject to any tax withholding obligations under applicable South African law. Each ordinary share of MNK outstanding on January 21, 2021, the record date for the Distribution (the “Record Date”), entitled the holder thereof to receive one share of the Company’s common stock.

-63-

On January 26, 2021, the Company closed the initial public offering of its common stock on the Nasdaq Capital Market (the “IPO”) with the shares traded under the symbol “MNTK”. Montauk Renewables issued 2,702,500 shares at $8.50 per share and received gross proceeds of $22,971. The Company’s common stock was also secondarily listed on the Johannesburg Stock Exchange (“JSE”) under the trading symbol “MKR”.

On January 26, 2021, the Company entered into a Loan Agreement and Secured Promissory Note (as amended on February 22, 2021, December 22, 2021, December 22, 2022, December 27, 2023 and March 5, 2025) with MNK pursuant to which the Company advanced a cash loan to MNK for MNK to pay its dividends tax liability arising from the Reorganization Transactions under the South African Income Tax Act, 1962 (Act No. 58 of 1962), as amended. The terms of the loan following the amendments are substantially similar to the initial loan agreement and were primarily entered into to (1) increase the principal amount outstanding under the loan to $10,690 in the aggregate (2) extended the maturity date to December 31, 2033 also, in accordance with Montauk Renewables’ obligations set forth in the Transaction Implementation Agreement ("TIA"). This loan became due on December 31, 2024 (“Maturity Date”) when MNK and RP47 did not extend the maturity of the loan agreement. Associated with a modification on December 31, 2024 of the TIA between us and MNK, we became obligated to repay the RP47 Loan on MNK’s behalf as MNK did not have sufficient funds to repay the RP47 Loan. On February 2, 2025, our Board of Directors approved the repayment of the RP47 Loan under the TIA. On March 5, 2025 and in connection with the Fifth Amended and Restated Loan Agreement and Secured Promissory Note", the Company repaid the RP47 loan as required under the TIA. In connection with the modification under the TIA, RP47 retained its power over MNK but no longer held significant benefits in MNK. Substantially all of MNK’s activities are conducted on our behalf as MNK’s only asset is the 976,623 shares of our common stock held as security for the Fifth Amended and Restated Loan Agreement and Secured Promissory Note. MNK’s only obligation was its loan to us and thus, we became the primary beneficiary of MNK on December 31, 2024. The Fifth Amended Promissory Note became an intercompany loan and was eliminated in consolidation. MNK’s investment of $10,178 in the Company was also eliminated in consolidation. There was no gain or loss on the initial consolidation of MNK as the transaction was a common control transaction. We also recorded a noncash acquisition of Treasury Stock ($8,309) related to the consolidation of the 976,623 shares of our Common Stock collateralizing the Fifth Amended Promissory Note. MNK is currently an affiliate of the Company and certain of the Company’s directors are also directors of MNK. See Note 17 for more information.

MNK was delisted from the JSE on January 26, 2021. The MNK Board of Directors and Shareholders held its annual general meeting in March 2023 and voted to take MNK private.

NOTE 2—SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

Principles of Consolidation

The historical consolidated financial information included reflects the historical results of operations and financial position of Montauk USA through January 4, 2021 when MNK sold the membership interest of Montauk USA. The consolidated financial statements of Montauk USA became the Company’s historical financial statements following the IPO. Certain historical financial information included relates to periods prior to the Reorganization Transactions. On December 31, 2024, the Company re-assessed its determination of the primary beneficiary of the Variable Interest Entity ("VIE") MNK under the guidance in ASC 810, Consolidation. Refer to Note 17 – Related Parties for further information. All intercompany balances and transactions have been eliminated in consolidation.

The Company utilizes the equity method of accounting for companies where its ownership is greater than 50% and significant but controlling interest does not exist.

Reclassifications

Certain prior period amounts have been reclassified to conform to the current period financial statement presentation. These

reclassifications had no effect on the previously reported total assets, total liabilities, stockholders’ equity, results of operations or cash

flows.

Segment Reporting

The Company reports segment information intwo segments: RNG and Renewable Electricity Generation. This is consistent with the internal reporting provided to the chief operating decision maker who evaluates operating results and performance. The aforementioned business services and offerings described in Note 1 are defined by management as two distinct operating segments: RNG and Renewable Electricity Generation. Below is a description of the Company’s operating segments and other activities.

The RNG segment represents the sale of gas sold at fixed-price contracts, counterparty share RNG volumes and applicable Environmental Attributes. This business unit represents the majority of the revenues generated by the Company. The Renewable

-64-

Electricity Generation segment represents the sale of captured electricity and applicable Environmental Attributes. Corporate & Other relates to additional discrete financial information for the corporate function. It is primarily used as a shared service center for maintaining functions such as executive, accounting, treasury, legal, human resources, tax, environmental, engineering and other operations functions not otherwise allocated to a segment. As such, the corporate entity is not determined to be an operating segment but is discretely disclosed for purposes of reconciliation to the Company’s consolidated financial statements.

Use of Estimates

The preparation of financial statements, in conformity with accounting principles generally accepted in the United States (“GAAP”), requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates.

Cash, Cash Equivalents and Restricted Cash

Cash and cash equivalents include highly liquid investments with maturity dates of three months or less from the date of purchase and are recorded at cost. The Company may hold cash in excess of federally insured limits. Restricted cash is classified as current or non-current based on the terms of the underlying agreements and represents cash held as deposits, cash held in escrow and cash collateral for financial letters of credit.

Accounts and Other Receivables

Accounts and other receivables on the Consolidated Balance Sheets represent outstanding billings for goods and services delivered to customers on an unsecured basis as well as reimbursable expenses. In evaluating its allowance for doubtful accounts for accounts receivable, the Company performs ongoing reviews of its outstanding receivables to determine if any amounts are uncollectible and adjusts the allowance for doubtful accounts accordingly.

Property, Plant and Equipment

Property, plant and equipment purchases are stated at cost, except for asset retirement obligations, which are recorded at estimated fair value at inception date. Depreciation and amortization are based on costs less estimated salvage values, primarily using the straight-line method over the estimated useful lives or, if applicable, the term of the related gas rights agreements or power purchase agreements, whichever is shorter. Maintenance and repairs are expensed as incurred. Major improvements that extend the useful lives of property are capitalized.

The estimated useful lives of the Company’s property, plant and equipment reflect the expected consumption of the economic benefit of these assets as noted in the following table:

Goodwill and Intangible Assets

Goodwill is the cost of an acquisition less the fair value of the identified net assets of the acquired business.

Separately identifiable intangible assets are recorded at their fair values upon acquisition. The Company accounts for its intangible assets in accordance with ASC 350, Intangibles—Goodwill and Other (“ASC 350”). Finite-lived intangible assets include interconnections, customer contracts and trade names & trademarks. The interconnection intangible asset is the exclusive right to utilize an interconnection line between the operating plant and a utility substation to transmit produced natural gas and electricity. Included in that right is full maintenance provided on this line by the utility. Intangible assets with finite useful lives are amortized on a straight-line basis over their estimated useful life as depicted in the chart below. Indefinite intangible assets are not amortized and include emission allowances and land use rights.

-65-

The estimated useful lives of separately identified intangible assets are as follows:

Leases

The Company assesses leases in accordance with ASU 2016-02, Leases, (“ASU 2016-02”). This ASU requires lessees to recognize a right-of-use asset and lease liability on the Consolidated Balance Sheet for leases classified as either operating or finance leases. For leases with a term of 12 months or less, a lessee is permitted to make an accounting policy election by class of underlying asset not to recognize a right-of-use asset and lease liability. Additionally, when measuring assets and liabilities arising from a lease, optional payments should be included only if the lessee is reasonably certain to exercise an option to extend the lease, exercise a purchase option, or not exercise an option to terminate the lease. A right-of-use asset represents an entity’s right to use the underlying asset for the lease term, and a lease liability represents an entity’s obligation to make lease payments. The measurement, recognition and presentation of expenses and cash flows arising from leases by a lessee remains the same. The Company has included further lease disclosures in Note 19.

Long-lived Asset Impairment

In accordance with ASC 360, Property, plant, equipment and intangible assets with finite useful lives are evaluated for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. Recoverability of assets to be held and used is measured by comparing the carrying amount of an asset or asset group to future undiscounted cash flows expected to be generated by the asset or asset group. Such estimates are based on certain assumptions, which are subject to uncertainty and may materially differ from actual results. If such assets are considered to be impaired, the impairment to be recognized is measured by the amount by which the carrying amount of the assets exceeds the fair value of the assets.

A summary of impairment losses on tangible and intangible assets for the year ended December 31, 2025, 2024 and 2023 is included in Note 3.

Indefinite-Lived Asset Impairment

Indefinite-lived intangible assets are required to be evaluated for impairment at least annually or whenever events or changes in circumstances indicate that the carrying value of the asset may not be recoverable. The evaluation of impairment under ASC 350 requires the use of projections, estimates and assumptions as to the future performance of the Company’s operations, including anticipated future revenues, expected operating costs and the discount factor used. Actual results may differ from projections. If such indefinite-lived assets are considered to be impaired, the impairment to be recognized is measured by the amount by which the carrying amount of the assets exceeds the fair value of the assets.

Asset Retirement Obligations

The Company accounts for asset retirement obligations as required under ASC 410, Asset Retirement and Environmental Obligations, (“ASC 410”). ASC 410 requires the fair value of a liability for an asset retirement obligation be recognized in the period in which the legal obligation arises, with the associated discounted asset retirement costs being capitalized as a part of the carrying amount of the long-lived asset and the annual accretion expense recorded in operations. The Company has recorded in the consolidated financial statements estimates for asset retirement obligations related to the decommissioning and removal requirements for specific gas processing and distribution assets, as required by their associated gas rights agreements.

Revenue

The Company recognizes revenue in accordance with ASC 606, Revenue from Contracts with Customers (“ASC 606”). Revenue from the Company’s point in time product sales is recognized when products are transferred, or services are invoiced and control transferred. Revenue from the Company’s product and service sales provided under long-term agreements is recognized as the Company transfers control of the product or renders service to its customers, which approximates the time when the customer is invoiced. The Company has presented the disclosures required by ASC 606 in Note 4.

-66-

Income Taxes

The Company is treated as a corporation for income tax purposes. Therefore, income taxes are accounted for under the liability method on a consolidated basis by the Company and its consolidated subsidiaries in accordance with ASC 740, Income Taxes (“ASC 740”). Deferred tax assets and liabilities are determined based on differences between financial reporting and tax bases of assets and liabilities and are measured using the enacted tax rates and laws. The provision for income taxes includes federal and state income taxes.

The Company recognizes the financial statement benefit of a tax position only after determining the relevant tax authority would more-likely-than-not sustain the position following an audit. For tax positions meeting the more-likely-than-not threshold, the amount recognized in the consolidated financial statements is the largest benefit that has a greater than 50 percent likelihood of being realized upon ultimate settlement with the relevant tax authority. The Company recognizes accrued interest and penalties related to unrecognized tax benefits in income tax expense.

Derivative Instruments

The Company applies the provisions of ASC 815, Derivatives and Hedging, (“ASC 815”). ASC 815 requires each derivative instrument to be recorded in the Consolidated Balance Sheets at its fair value. Changes in a derivative instrument’s fair value are recognized currently in earnings.

Fair Value of Financial Instruments

The Company employs varying methods and assumptions in estimating the fair value of each class of financial instruments for which it is practical to estimate fair value. For cash and cash equivalents, receivables and payables, the carrying amounts approximate fair value due to the short maturity of these instruments. For long-term debt, the carrying amounts approximate fair value as the interest rates obtained by the Company approximate the prevailing interest rates available to the Company for similar instruments.

In accordance with ASC 820, Fair Value Measurement (“ASC 820”), a hierarchy is established which requires an entity to maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value. The hierarchy defines three levels of inputs that may be used to measure fair value:

Level 1—Unadjusted quoted prices in active markets for identical unrestricted assets and liabilities that the reporting entity has the ability to access at the measurement date.

Level 2—Inputs other than quoted prices included within Level 1 that are observable for the assets and liabilities or can be corroborated with observable market data for substantially the entire contractual term of the assets or liabilities.

Level 3—Unobservable inputs that reflect the entity’s own assumptions about the assumptions market participants would use in the pricing of the assets or liabilities and are consequently not based on market activity but rather through particular valuation techniques. The Company uses the fair value methodology to value the assets and liabilities recorded at fair value, including the Company’s asset retirement obligations and earn out liability.

The values of the Level 2 interest rate derivatives were determined using a model, which incorporates market inputs including the implied forward interest rate yield curve for the same period as the future interest rate swap settlement. The Company has also considered both its own credit risk and counterparty credit risk in determining fair value and determined these adjustments were insignificant for the years ended December 31, 2025 and 2024. The Company’s asset retirement obligations are recorded at fair value at the time the liability is incurred if a reasonable estimate of fair value can be made. Fair value is determined by calculating the estimated present value of the cost to retire the asset as determined by qualified engineers, based on currently available information and inflation estimates and is considered a Level 3 measurement. The Company’s earn-out liability fair value is determined by calculating the estimated present value of future obligations based on currently available information and the discount factor used and is considered a Level 3 measurement.

A summary of changes in the fair values of the Company’s Level 3 instruments, attributable to asset retirement obligations and the earn out liability, for the years ended December 31, 2025 and 2024 is included in Note 11.

Renewable Identification Numbers (“RINs”)

The Company generates D3 RINs through its production and sale of RNG used for transportation purposes as prescribed under the Federal Renewable Fuel Standard. The RINs that the Company generates as government incentives through its renewable operating projects can be separated and sold as credits independent from the energy produced and not a result of physical attributes of the Company’s production. Therefore, no cost is allocated to the RIN when it is generated. Revenue is recognized on these

-67-

Environmental Attributes when there is an agreement in place to monetize the credits at an agreed upon price with a customer and transfer of control has occurred. Realized prices for Environmental Attributes monetized in a year may not correspond directly to index prices due to the forward selling of commitments. The Company hadzero and 6.8 million RINs generated and unsold as of December 31, 2025 and 2024, respectively.

Renewable Energy Credits (“RECs”)

The Company generates RECs through its production and sale of landfill methane into renewable electric energy as prescribed by the State of California Renewables Portfolio Standard or the EPA. The RECs that the Company generates as government incentives through its renewable operating projects are able to be separated and sold as credits independent from the electricity produced and not a result of physical attributes of the Company’s production. Therefore, no cost is allocated to the REC when it is generated. Revenue is recognized on these Environmental Attributes when there is an agreement in place to monetize the credits at an agreed upon price with a customer and transfer of control has occurred.

Equity-Based Compensation

The Company accounts for equity-based compensation under the provisions of ASC 718, Compensation—Stock Compensation, (“ASC 718”). ASC 718 requires compensation costs related to share-based payment transactions, measured based on the fair value of the instruments issued, be recognized in the consolidated financial statements over the requisite service period of the award. Stock options are initially measured on the grant date using the Black-Scholes valuation model, which requires the use of subjective assumptions related to the expected stock price volatility, term, risk-free interest rate and dividend yield. For restricted stock shares, the Company determines the grant date fair value based on the closing market price of the stock on the date of the grant. Forfeitures are recognized when they occur.

Employee Benefits

Leave entitlement

Employee entitlements to annual leave are recognized when they accrue to employees. An accrual is made for the estimated liability to the employees for annual leave up to the financial year end date. This liability is included in “Accrued liabilities” in the Consolidated Balance Sheets.

Bonus Plans

The Company recognizes a liability and an expense for incentive compensation bonuses awarded based on the achievement of Company and personnel goals where contractually obliged or where there is a past practice that has created a constructive obligation. An accrual is maintained for the appropriate proportion of the expected bonuses which would become payable at year end.

Recently Adopted Accounting Standards

In December 2025, the FASB issued ASU No. 2025-07, Derivatives and Hedging (Topic 815) and Revenue from Contracts with Customers (Topic 606): derivatives scope refinements and scope clarification for share-based noncash consideration from a customer in a revenue contract. This ASU (1) refines the scope of the guidance on derivatives in ASC 815 (Issue 1) and (2) clarifies the guidance on share-based payments from a customer in ASC 606 (Issue 2). The Company has adopted the standard retrospectively, as of December 31, 2025.

In December 2023, the FASB issued ASU No. 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures. The amendments in 2023-09 aim to enhance the transparency and decision usefulness of income tax disclosures. ASU 2023-09 is effective for the Company's Annual Report on Form 10-K for the year ended December 31, 2025, with early adoption permitted. The Company has adopted the standard retrospectively, and the enhanced expense disclosures can be found in Note 14.

Recently Issued Accounting Standards

In November 2024, the FASB issued ASU 2024-03, Income Statement — Reporting Comprehensive Income — Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses. This ASU requires public business entities to disclose, on an annual and interim basis, disaggregated information about certain income statement expense line items. The ASU also requires disclosure of the total amount of selling expenses recognized in continuing operations on an annual and interim basis and disclosure of a public business entity’s definition of selling expenses on an annual basis (or in interim reporting periods if the definition is changed). Public business entities are required to apply the guidance prospectively but are permitted to apply it retrospectively. The ASU is effective for fiscal years beginning after December 15, 2026, and interim periods within fiscal years beginning after December 15, 2027. The Company is currently evaluating the impact of this standard on its consolidated financial statements.

-68-

NOTE 3—ASSET IMPAIRMENT

The Company recorded $3,231, $1,586 and $902 in impairment losses for the years ended December 31, 2025, 2024 and 2023, respectively. In 2025, $2,676 was impaired for costs related to an RNG development project for which the local utility is no longer accepting RNG into its distribution system. All associated costs other than a gas rights development payment related to the project were impaired. The remaining 2025 impairments of $555 were for specifically identified assets deemed obsolete or non-operable and consisted of $432 within the RNG segment, $120 within the REG segment and $3 within the Corporate segment. In 2024, forone of its REG sites, the Company entered into a bill of sale, assignment and assumption agreement to sell its rights to the existing fuel supply agreement and property back to the site host in advance of the fuel supply agreement termination date and received $1,000 in proceeds. The effective date of the sale, assignment and assumption agreement was October 1, 2024. The Company elected to cease operations prior to the assignment date and consequently the remaining book value of long lived assets and intangibles were impaired for $312. The $1,000 in proceeds received was recognized as Other income in the Consolidated Statement of Operations. In addition, $329 in REG impaired assets were due to initial startup testing failures for one of its REG construction work in progress sites. Remaining 2024 impairments, $843 in RNG assets and $102 in REG assets, were for various equipment that was deemed obsolete or inoperable for current operations. 2023 impairments included $777 for specifically identified RNG machinery and feedstock processing equipment that were no longer in operational use and recorded in the Company's RNG segment. The remaining $125 in impairments were for specifically identified obsolete REG critical spares.

Impairment loss was recorded under Operating expenses within the Consolidated Statements of Operations for the years ended December 31, 2025, 2024, and 2023.

NOTE 4—REVENUES FROM CONTRACTS WITH CUSTOMERS

The Company’s revenues are comprised of renewable energy and related Environmental Attribute sales provided under short, medium and long term contracts with its customers. All revenue is recognized when (or as) the Company satisfies its performance obligation(s) under the contract (either implicit or explicit) by transferring the promised product or service to its customer either when (or as) its customer obtains control of the product or service. A performance obligation is a promise in a contract to transfer a distinct product or service to a customer. A contract’s transaction price is allocated to each distinct performance obligation. The Company allocates the contract’s transaction price to each performance obligation using the product’s observable market standalone selling price for each distinct product in the contract. The Company's typical invoicing terms are payment due within 30 days.

Revenue is measured as the amount of consideration the Company expects to receive in exchange for transferring its products or services to customers. Revenue is recorded net of allowances and customer discounts. Transportation and gathering costs incurred by customers after the transfer of control of the commodities are netted from revenue, as the Company does not control these services and acts as an agent with respect to such costs. To the extent applicable, sales, value add and other taxes collected from customers and remitted to governmental authorities are accounted for on a net (excluded from revenues) basis. In certain cases, the Company's performance obligation under its sale of RNG contracts include variable components, whose consideration is based on subsequent monetization of environmental attribute credits by third parties. These variable components are recognized over time to the extent it is probable that a significant reversal will not occur.

The Company’s performance obligations related to the sale of renewable energy (i.e. RNG and Renewable Electricity) are generally satisfied over time. Revenue related to the sale of renewable energy is generally recognized over time using an output based upon the product quantity delivered to the customer. This measure is used to best depict the Company’s performance to date under the terms of the contract. Revenue from products transferred to customers over time accounted for 33%,26% and 24% of revenue for the years ended December 31, 2025, 2024 and 2023, respectively.

The Company’s performance obligations related to the sale of Environmental Attributes are generally satisfied at a point in time and were 67%,74% and 76% of revenue for the years ended December 31, 2025, 2024 and 2023, respectively. The Company recognizes Environmental Attribute revenue at the point in time in which the customer obtains control of the Environmental Attributes, which is generally when the title of the Environmental Attribute passes to the customer upon delivery. In limited cases, title does not transfer to the customer and revenue is not recognized until the customer has accepted the Environmental Attributes.

-69-

The following tables display the Company’s disaggregated revenue by major source, based on product type and timing of transfer of goods and services for the years ended December 31, 2025, 2024 and 2023:

Practical expedients and remaining performance obligations

The Company recognizes the sale of natural gas and electric commodities using the right to invoice practical expedient. The Company determined that the revenues recognized as of period end correspond directly with the value transferred to customers and the Company's satisfaction of the performance obligations to date. Furthermore, with the application of the right to invoice practical expedient and in consideration that contracts related to future environmental attributes sales do not exceed one year, there are no remaining unsatisfied or partially satisfied performance obligations as of December 31, 2025.

NOTE 5—EQUITY METHOD INVESTMENTS

In March 2025, the Company entered into a joint venture, GreenWave Energy Partners, LLC, ("GreenWave"). The investees in the joint venture are Pesta Energy, LLC, a wholly owned subsidiary of the Company, with an ownership percentage of 51% and Pioneer Renewable Energy Marketing, LLC ("PREM"), with an ownership percentage of 49%. Although the Company holds a 51%

-70- ownership interest, GreenWave is jointly controlled by each party, and no single entity has the unilateral ability to direct the activities that most significantly impact GreenWave’s economic performance; accordingly, consolidation is not required. As of December 31, 2025, the Company has contributed $4,000. Additionally, the Company provided for a $167 short-term loan. Subject to various and certain requirements as defined in the underlying agreements, the Company could be required to make additional short term loans up to $333. Any additional funding, if required, would be evaluated at the time of funding to determine the appropriate accounting treatment. The joint venture is primarily intended to help address the limited capacity of RNG usage in transportation by dispensing RNG through expanded Transportation Fuel uses under the RFS. While the joint venture is not expected to use RNG produced by the Company, it is expected to provide access to exclusive unique and proprietary pathways for other industry producers of RNG. PREM facilitates access to these pathways and the Company provides for the efficient RIN separation for the joint venture. As part of the agreement, the Company receives separated RINs as distributions. For the year ended December 31, 2025, the Company received 706 RINs with a distribution value of $1,661. The distributions of separated RINs are accounted for as a return on investment and are recognized based on the Company’s share of GreenWave’s earnings, with any excess distributions treated as a return of investment and recorded as a reduction of the carrying amount of the equity method investment. For the year ended December 31, 2025, the Company recorded $1,485 in income from the joint venture. As of December 31, 2025, the Company had a non-consolidated equity method investment of $3,824.

The Company utilizes the equity method of accounting related to this joint venture. Refer to Note 2 – Summary of

Significant Accounting Policies.

NOTE 6—ACCOUNTS AND OTHER RECEIVABLES

The Company extends credit based upon an evaluation of the customer’s financial condition. Credit terms are consistent with industry standards and practices. Accounts Receivable consist of sales to large creditworthy energy and utility companies. Reserves for uncollectible accounts, if any, are recorded as part of general and administrative expenses in the Consolidated Statements of Operations. No reserve expense was recorded for the years ended December 31, 2025, 2024 and 2023.

Accounts and other receivables consist of the following as of December 31, 2025, 2024 and 2023:

NOTE 7—PROPERTY, PLANT AND EQUIPMENT, NET

Property, plant and equipment consists of the following as of December 31, 2025 and 2024:

Depreciation expense for Property, plant and equipment was $28,420, $22,096 and $19,624 and Depletion expense for gas mineral rights was $364, $365 and $489 for the years ended December 31, 2025, 2024 and 2023, respectively.

Construction work in progress consists of RNG and REG capital expenditures on developmental projects and improvements to existing sites. Projects, on average, last between 18 to 36 months, and when completed for their intended use, costs are placed in service and begin depreciating.

In February 2024, the Company completed an Asset acquisition with a privately-held entity. The Company paid $820 forland located in North Carolina. The Asset acquisition was accounted for as an asset purchase in accordance with ASC 805, Business

-71-

Combinations, and the purchase price has been allocated all to land within Property, plant and equipment, net on the Company's consolidated balance sheet.

In February 2024, for one of its REG sites, the Company entered into a bill of sale, assignment and assumption agreement to sell its rights to the existing fuel supply agreement and property back to the site host in advance of the fuel supply agreement termination date and received $1,000 in proceeds. The effective date of the sale, assignment and assumption agreement was October 2024. See Note 3 for impairment charges related to this site.

In October 2024, the Company entered into an asset purchase agreement to sell one of its immaterial RNG sites for a purchase price of $1,000. The Company entered into this agreement with the site host in advance of the expiration of the gas rights agreement. The company sold all of the site's assets and a $73 gain was recognized for the year ended December 31, 2024.

NOTE 8—GOODWILL AND INTANGIBLE ASSETS, NET

Goodwill and Intangible assets consist of the following as of December 31, 2025 and December 31, 2024:

The weighted average remaining useful life of the customer contracts and interconnections are approximately 12 and 13 years, respectively. Amortization expense was $1,117, $986 and $972 for the years ended December 31, 2025, 2024 and 2023, respectively.

Amortization expense for customer contracts and interconnections for the next five years is as follows:

NOTE 9—ASSET RETIREMENT OBLIGATIONS

The Company accounts for asset retirement obligations by recording the fair value of the liability in the period in which it is incurred. The Company estimates the fair value of asset retirement obligations by calculating the estimated present value of the cost to retire the asset. Factors that are considered when determining the present value of the cost to retire the asset include future inflation and discount rates, along with estimates date(s) of retiring the asset. Additionally, changes in legal, regulatory, environmental, and political environments can affect the fair value of the obligations. As such, asset retirement obligations are considered a level 3 financial instrument.

The 2025 $137 ARO addition was due an RNG expansion project placed into service. The $218 change in estimates for the year ended December 31, 2024 was due to RNG fuel supply agreement extensions and an RNG project that necessitated reassessment. The $225 reduction in the liability was due to an REG site sale as described in Note 3.

-72-

The following table summarizes the activity associated with asset retirement obligations of the Company for the years ended December 31, 2025, 2024 and 2023:

NOTE 10—DERIVATIVE INSTRUMENTS

To mitigate market risk associated with fluctuations in interest rates, the Company utilizes various derivative contracts to secure interest rates under a board-approved program. The Company does not apply hedge accounting to any of its derivative instruments, and all realized and unrealized gains and losses from changes in derivative values are recognized in earnings each period. As a result of the economic hedging strategies employed, the Company had the following interest expense in the Consolidated Statements of Operations for the years ended December 31, 2025, 2024 and 2023:

NOTE 11—FAIR VALUE OF FINANCIAL INSTRUMENTS

The Company’s assets and liabilities that are measured at fair value on a recurring basis include the following as of December 31, 2025 and 2024, set forth by level, within the fair value hierarchy:

Interest rate swap derivatives are classified as Level 2 financial instruments and are valued utilizing Secured Overnight Financing Rates. In addition, certain assets are measured at fair value on a non-recurring basis when an indicator of impairment is identified and the assets’ fair values are determined to be less than its carrying value. See Note 3 for additional information.

A summary of changes in the fair value of the Company’s Level 3 instrument, attributable to asset retirement obligations, for the years ended December 31, 2025, 2024 and 2023 is included in Note 9. The Company’s earn-out fair value liability at its Idaho agricultural digester site was determined by calculating the estimated present value of the future obligation. The present value was assessed quarterly and was based on macro-economic factors such as inflation and risk free US Treasury rates. Company specific estimates utilized included current and future interest rates, digester inlet gas flow and projected EBITDA. A weighted average probability approach was utilized for the variables discussed above. The undiscounted maximum payout of the earn-out ranged between 5% and 20% of EBITDA based on average inlet gas production ranging from 641 standard cubic feet per minute ("scfm") to greater than 944 scfm for each semiannual period in the remaining term, as defined in the underlying agreement. In December 2025, the Company settled the earnout obligation for $4,000. The earn-out was classified as a Level 3 financial instrument and changes in

-73- thebalance are recorded in Accrued liabilities and Other liabilities within the Consolidated Balance Sheets and in Royalties, transportation, gathering and production fuel within the Consolidated Statements of Operations.

There wereno transfer of assets or liabilities between Levels 1, 2 or 3 of the fair value hierarchy as of December 31, 2025 and 2024.

NOTE 12—ACCRUED LIABILITIES

The Company’s accrued liabilities consists of the following as of December 31, 2025 and December 31, 2024:

NOTE 13—DEBT

On March 9, 2026, the Company refinanced its entire debt maturing in December 2026 with a New Senior Credit Facility with a new lender. Under ASC 470-10-45-14 guidance, the Company classified its existing debt as $2,733 as short term debt and $126,000 as long term debt as of December 31, 2025. Please refer to Note 22 – Subsequent Events for further discussion.

The Company’s debt consists of the following as of December 31, 2025 and December 31, 2024:

Amended Credit Agreement

On December 12, 2018, Montauk Energy Holdings LLC (“MEH”) entered into the Second Amended and Restated Revolving Credit and Term Loan Agreement (as amended, “Credit Agreement”), by and among MEH, the financial institutions from time to time party thereto as lenders and Comerica Bank, as the administrative agent, sole lead arranger and sole bookrunner (“Comerica”). The Credit Agreement (i) amended and restated in its entirety MEH’s prior revolving credit and term loan facility, dated as of August 4, 2017, as amended, with Comerica and certain other financial institutions and (ii) replaced in its entirety the prior credit agreement, dated as of August 4, 2017, as amended, between Comerica and Bowerman Power LFG, LLC, a wholly-owned subsidiary of MEH.

On March 21, 2019, MEH entered into the first amendment to the Credit Agreement which clarified a variety of terms, definitions and calculations in the Credit Agreement. The Credit Agreement requires the Company to maintain customary affirmative and negative covenants, including certain financial covenants, which are measured at the end of each fiscal quarter.

On August 28, 2019, the Company received a temporary waiver for an anticipated Event of Default (as defined in the Credit Agreement) for the consecutive three-month period ended on August 31, 2019 (the “Specified Event of Default”). The Specified Event of Default was waived through October 1, 2019.

On September 12, 2019, the Company entered into the second amendment to the Credit Agreement (the "Second Amendment"). Among other matters, the Second Amendment redefined the Fixed Charge Coverage Ratio (as defined in the Credit Agreement), reduced the commitments under the revolving credit facility to $80,000, redefined the Total Leverage Ratio (as defined in the Credit Agreement) and eliminated the RIN Floor (as defined in the Second Amendment) as an Event of Default. In connection with the

-74-

Second Amendment, the Company paid down the outstanding term loan by $38,250 and the resulting quarterly principal installments were reduced to $2,500

On January 4, 2021, the Company, Montauk Holdings Limited (“MNK”) and Montauk Holdings USA, LLC (a direct wholly-owned subsidiary of MNK at the time, “Montauk USA”) entered into a series of transactions, including an equity exchange and a distribution collectively referred to as the “Reorganization Transactions,” that resulted in the Company owning all of the assets and entities (other than Montauk USA) previously owned by Montauk USA, and Montauk Renewables became a direct wholly-owned subsidiary of MNK. In connection with the completion of the Reorganization Transactions and the IPO, the Company entered into the third amendment to the Credit Agreement (the “Third Amendment”). This amendment permitted the change of control provisions, as defined in the underlying agreement, to permit the Reorganization Transactions and the IPO to be completed.

On December 21, 2021, MEH entered into the Fourth Amendment to the Second Amended and Restated Revolving Credit and Term Loan Agreement. The current credit agreement, which is secured by a lien on substantially all assets of the Company and certain of its subsidiaries, provides for a $80,000 term loan and a $120,000 revolving credit facility. The term loan amortizes in quarterly installments of $2,000 through 2024, then increases to $3,000 from 2025 to 2026 with a final payment of $32,000 in late 2026.

The Company accounted for the Fourth amendment as both a debt modification and debt extinguishment in accordance with ASC 470, Debt (“ASC 470”). In connection with the Credit Agreement, the Company paid $2,027 in fees. Of this amount, $326 was expensed and $1,701 was capitalized and will be amortized over the life of the Credit Agreement. Amortized debt issuance expense in the amount of $391, $360 and $367 for the years ended December 31, 2025, 2024 and 2023, respectively, was recorded in interest expense in the Consolidated Statement of Operations. Unamortized debt issuance cost on the revolver was $601 and $479 as of December 31, 2025 and 2024, respectively.

On November 8, 2024, MEH entered into the Fifth Amendment to the Second Amended and Restated Revolving Credit and Term Loan Agreement. The Fifth amendment replaced the Bloomberg Short-Term Bank Yield Index Rate utilized for interest rates with the Secured Overnight Financing Rate Index ("SOFR"), plus applicable margin.

On December 31, 2025, MEH entered into the Sixth Amendment to the Second Amended and Restated Revolving Credit and Term Loan Agreement. The Sixth Amendment redefined the Total Net Leverage Ratio and accelerated the presentment of monthly unaudited financial statements to Comerica, along with the requirement of an engineering study and independent engineer's certificate as it relates to operations in North Carolina by June 3, 2026. As part of the Sixth Amendment, the Company was required to pay $515 to Comerica and the bank syndicate. Of this amount, $120 was expensed and the remainder amount was capitalized and will be amortized over the life of the Credit Agreement.

As of December 31, 2025, $44,000 and $85,000 was outstanding under the term loan and revolver, respectively. In addition, the Company had $2,571 of outstanding letters of credit as of December 31, 2025. Amounts available under the revolving credit facility are reduced by any amounts outstanding under letters of credit. As of December 31, 2025, the Company’s capacity available for borrowing under the revolving credit facility was $32,429. Borrowings of the term loan and revolving credit facility bear interest at the Secured Overnight Financing Rate plus an applicable margin. Interest rates as of December 31, 2025 and 2024 were 6.44% and 6.01%, respectively.

As of December 31, 2025, the Company was in compliance with all applicable debt covenants related to the Credit Agreement with Comerica Bank. Please refer to Note 22 – Subsequent Events for discussion of the New Senior Credit Facility that the Company entered into on March 9, 2026.

Annual Maturities of Long-Term Debt

The following is a summary of annual principal maturities of long-term debt as of December 31, 2025:

NOTE 14—INCOME TAXES

The Company is subject to income taxes in the U.S. federal jurisdiction and various state and local jurisdictions. Tax regulations within each jurisdiction are subject to the interpretation of the related tax laws and regulations and require significant judgment to apply.

-75-

The following table details the components of the Company’s income tax provision for the years ended December 31, 2025, 2024 and 2023:

The following table illustrates the deferred tax assets and liabilities as of December 31, 2025 and December 31, 2024:

As of December 31, 2025, the Company has $2,727 (tax affected) of federal net operating losses carryforwards that are not expected to be realizable due to restrictive loss limitation rules. As such a full valuation allowance has been recorded to offset the value of the related carryforward. As of December 31, 2025, the Company has $1,335 state net operating loss carryforwards. A partial valuation allowance has been recorded to recognize that some attributes may expire before utilization. Additionally, the Company has $17,339 of federal tax credit carryforwards that expire 20 years from the date earned. The credits available as of December 31, 2025 will begin to expire in 2039.

The following table details the components of the Company’s income tax provision for the years ended December 31, 2025, 2024 and 2023:

-76-

State taxes in Pennsylvania and Texas comprise the majority of the state and local income taxes, net of federal effect category in all presented years.

As of December 31, 2025, the tax years 2022, 2023 and 2024 are open for examination by the IRS.

Valuation Allowance

The Company annually reviews its deferred tax assets for the possibility they will not be realized. A valuation allowance will be recorded if it is determined more than a 50% likelihood exists that a deferred tax asset will not be realized. A $4,542 valuation allowance exists as of December 31, 2025 and 2024, which represents the Company’s deferred tax assets that are not expected to be realized. $565 of the valuation allowance represents MNK's investment deferred tax assets that the Company does not expect to realize. Refer to Note 17, Related Party Transactions for further information regarding the consolidation of MNK on December 31, 2024.

Uncertain Tax Position

The calculation of the Company’s tax liabilities involves dealing with uncertainties in the application of complex tax laws and regulations in both federal and state jurisdictions. ASC 740 states that a tax benefit from an uncertain tax position may be recognized when it is more likely than not that the position will be sustained upon examination, including resolutions of any related appeals or litigation processes, on the basis of each situation’s technical merits.

At this point in time the Company is not aware of any tax positions taken that would give rise to recording an uncertain tax position. As such, the Company has not recorded any liability for unrecognized tax benefits as of December 31, 2025 or 2024. The Company records interest and penalties as a component of income tax expense. However, as there areno unrecognized tax benefits for the years ended December 31, 2025 and December 31, 2024, the Company hasno penalties or interest accrued at December 31, 2025 and 2024, respectively.

-77-

NOTE 15—SHARE-BASED COMPENSATION

The board of directors of Montauk Renewables adopted the Montauk Renewables, Inc. Equity and Incentive Compensation Plan (“MRI EICP”) in January 2021. Following the closing of the IPO, the board of directors of Montauk Renewables approved the grant of non-qualified stock options, restricted stock units and restricted share awards to the employees of Montauk Renewables and its subsidiaries in January 2021. In connection with the restricted share awards, the officers of the Company made elections under Section 83(b) of the Code. Pursuant to such elections, the Company withheld 950,214 shares of common stock from such awards at a price of $11.38 per share from such awards. The Company records and reports restricted shares and restricted stock units when vested and in the case of options, when such awards are settled in the Company’s common stock. Stock compensation expense related to these awards was $718, $1,470 and $1,723 for the years ended December 31, 2025, 2024 and 2023, respectively.

In connection with a May 2021 asset acquisition,1,250,000 restricted share awards (“RS Awards”) were granted totwo employees that were hired by the Company in connection with the acquisition. The RS Awards were to vest over a five-year period and subject to the achievement of time and performance-based vesting criteria over such period. In May 2022, the RS Awards were amended to remove the performance-based vesting criteria and were only subjected to time-based vesting requirements over a five-year period. The awards were revalued at $15,500. Stock compensation expense related to the two awards was $1,862, $5,866 and $4,908 for the year ended December 31, 2025, 2024 and 2023, respectively. Due to two employee terminations, $1,550 and $2,911 in accelerated noncash stock compensation expense was recognized in 2025 and 2024, respectively, within the line item General and administration expense. No additional compensation expense remains for these RS awards.

In 2023, the board of directors of the Company approved the grant of non-qualified stock options to the executive officers of the Company, which vest ratably over a period of three to five years. Stock compensation expense related to these awards was $1,869, $2,629 and $1,692 for the years ended December 31, 2025, 2024 and 2023, respectively.

The restricted shares, restricted stock units and option awards are subject to vesting schedules and are subject to the terms and conditions of the MRI EICP and related award agreements including, in the case of the restricted share awards, each officer having made an election under Section 83(b) of the Code.

Options granted under the MRI EICP allow the recipient to receive the Company’s common stock equal to the appreciation in the fair market value of the Company’s common stock between the grant date and the exercise and settlement of options into shares as of the exercise date(s). The fair value of the MRI EICP options was estimated using the Black-Scholes option pricing model with the following weighted-average assumptions (no dividends were expected):

-78-

The following table summarizes the restricted shares, restricted stock units and options outstanding under the MRI EICP for the years ended December 31, 2025, 2024 and 2023:

Unrecognized MRI EICP compensation expense for awards the Company expects to vest as of December 31, 2025, was $2,945 and will be recognized over approximately 2.3 years.

NOTE 16—DEFINED CONTRIBUTION PLAN

The Company maintains a 401(k) defined contribution plan for eligible employees. The Company matches 50% of an employee’s deferrals up to 4%. The Company also contributes 3% of eligible employee’s compensation expense as a safe harbor contribution. The matching contributions vest ratably over four years of service, while the safe harbor contributions vest immediately. Incurred expense related to the 401(k) plan was $867, $796 and $640 for the years ended December 31, 2025, 2024 and 2023, respectively.

NOTE 17—RELATED-PARTY TRANSACTIONS

Related Party Loan

On January 26, 2021, the Company entered into a Loan Agreement and Secured Promissory Note (the “Initial Promissory Note”) with Montauk Holdings Limited (“MNK”). MNK is currently an affiliate of the Company and certain of the Company’s directors are also directors of MNK. Pursuant to the Initial Promissory Note, the Company advanced a cash loan of $5,000 to MNK for MNK to pay its dividend's tax liability arising from the Reorganization Transactions under the South African Income Tax Act, 1962 (Act No. 58 of 1962), as amended (the “South African Income Tax Act”). On February 22, 2021, the Company and MNK entered into an Amended and Restated Promissory Note (the “Amended Promissory Note”) to increase the principal amount of the loan to a total of $7,140, in the aggregate, on December 22, 2021 entered into the Second Amended and Restated Loan Agreement and Secured Promissory Note (the “Second Amended Promissory Note”) to increase the principal amount of the loan to a total of $8,940, in the aggregate, and on December 22, 2022 entered into the First Amendment of the Second Amended and Restated Loan Agreement and Secured Promissory Note (the “First Amendment of Second Amended Promissory Note”) to amend the maturity date to June 30, 2023, and on June 21, 2023 entered into the Third Amended and Restated Loan Agreement and Secured Promissory Note (the "Third Amended and Restated Loan Agreement and Secured Promissory Note") to increase the principal amount of the loan to a total of $10,040, in the aggregate and extend the maturity date of the loan to December 31, 2023 and on December 27, 2023 entered into the Fourth Amended and Restated Loan Agreement and Secured Promissory Note to extend the maturity date of the loan to December 31, 2033, and on March 5, 2025 entered into the Fifth Amended and Restated Loan Agreement and Secured Promissory Note (the "Fifth Amended and Restated Loan Agreement and Secured Promissory Note") to increase the principal amount of the loan to a total of $10,690, in the aggregate, each in accordance with the Company’s obligations set forth in the TIA entered into by and among the Company, MNK and the other party thereto, dated November 6, 2020, and amended on January 14, 2021 and on December 31, 2024.

-79-

The"Third Amended and Restated Loan Agreement and Secured Promissory Note" increased the security interest of the Company from 800,000 shares of the common stock of the Company owned by MNK to 976,623 shares of the Company. MNK is required to use the proceeds of any such sale of the shares to repay the note. The Amended Promissory Note has default provisions where MNK will deliver any unsold shares of the Company back to the Company to satisfy repayment of the note No other terms were amended under the Fifth Amended and Restated Loan Agreement and Secured Promissory Note and the security interest of the Company from MNK remains 976,623 shares of the Company and the maturity remains December 31, 2033.

In December 2021, Rivetprops 47 Proprietary Limited (“RP47”) entered into an agreement to loan MNK up to 10,000 South African Rand (the “RP47 Loan”). The principal balance and accrued interest as of December 31, 2024 was 11,713 Rand or approximately $650 US Dollars. There was no collateral pledged for this loan. This loan became due on December 31, 2024 (“Maturity Date”) when MNK and RP47 did not extend the maturity of the loan agreement. Associated with a modification on December 31, 2024 of the TIA between us and MNK, we became obligated to repay the RP47 Loan on MNK’s behalf as MNK did not have sufficient funds to repay the RP47 Loan. On February 2, 2025, our Board of Directors approved the repayment of the RP47 Loan under the TIA. On March 5, 2025 and in connection with the Fifth Amended and Restated Loan Agreement and Secured Promissory Note", the Company repaid the RP47 loan as required under the TIA.

Variable Interest Entities

Under ASC 810-10-25-38A and 38B, a reporting entity is deemed to have a controlling financial interest in a VIE if it possesses both of the following characteristics: the power to direct the activities of the VIE that most significantly impact its economic performance, and the obligation to absorb losses of the VIE that could potentially be significant or the right to receive benefits from the VIE that could potentially be significant.

Under ASC 810, the Company determined that MNK is a variable interest entity. The Company does not hold any equity interest in MNK but has entered into the Fifth Amended and Restated Loan Agreement and Secured Promissory Note between the Company and MNK.

Prior to the RP47 Loan repayment, we concluded that RP47, a related party of us through RP47’s ownership of MNK, was the primary beneficiary of MNK under the variable interest entity model. In connection with the modification under the TIA, RP47 retained its power over MNK but no longer held significant benefits in MNK. Substantially all of MNK’s activities are conducted on our behalf as MNK’s only asset is the 976,623 shares of our common stock held as security for the Fifth Amended and Restated Loan Agreement and Secured Promissory Note. MNK’s only obligation is its loan to us and thus, we became the primary beneficiary of MNK on December 31, 2024. In accordance with ASC 810, we consolidated MNK on December 31, 2024. The Fifth Amended Promissory Note became an intercompany loan and was eliminated in consolidation. MNK’s investment of $10,178 in the Company was also eliminated in consolidation. There was no gain or loss on the initial consolidation of MNK as the transaction is a common control transaction. We also recorded a noncash acquisition of Treasury stock ($8,309) related to the consolidation of the 976,623 shares of our Common stock collateralizing the Fifth Amended Promissory Note. As of December 31, 2025, MNK amounts consolidated into MRI's consolidated balance sheet were $66 cash, $45 other current assets, $32 accrued liabilities and $39 in other long term liabilities.

Employment Transactions

The Company signed a long-term immaterial lease in December 2023 with a landowner in North Carolina. This lease enabled the Company to construct a feedstock collection system on the property which is owned by the Company. In September 2024, the Company hired the landowner as an employee to assist in the procuring of additional long-term leases on farms for additional collection system installations related to feedstock in North Carolina.

NOTE 18—SEGMENT INFORMATION

The Company’s reportable segments for the years ended December 31, 2025, 2024 and 2023 are Renewable Natural Gas and Renewable Electricity Generation. Renewable Natural Gas includes the production of RNG. Renewable Electricity Generation includes generation of electricity at biogas-to-electricity plants. The Corporate entity is not determined to be an operating segment and though not an operating segment, certain corporate costs are disclosed as reconciling items to the Company’s consolidated results. The following tables are consistent with the manner in which the Chief Executive Officer, who is the Company's chief operating decision maker ("CODM"), evaluates the performance of each segment and allocates the Company's resources. The CODM evaluates the performance of the segments based on segment operating income (loss). The Company maintains discrete financial information for its operating sites, which meet the definition of an operating segment, but are aggregated into reportable segments based on the type of commodity produced, as these operating sites have similar economic characteristics, including production processes, customer types and regulatory environments. Total Assets and Capital expenditures by segment are also provided within the tables below, as these

-80- amountsare regularly reviewed by the CODM. “RNG” refers to Renewable Natural Gas and “REG” refers to Renewable Electricity Generation.

(3)The majority of operating expenses for Corporate and other are payroll and related expenses of $19,152, insurance of $4,646 and professional and IT fees of $4,843.

(4)The majority of other expense (income) for Corporate and other are interest expense of $4,816 and income from equity investment of ($1,485).

-81-

(3)The majority of operating expenses for Corporate and other are payroll and related expenses of $23,847, insurance of $5,488 and professional and IT fees of $4,141.

(4)The majority of other expense (income) for Corporate and other is interest expense of $5,276.

-82-

(3)The majority of operating expenses for Corporate and other are payroll and related expenses of $20,396, insurance of $5,951 and professional and IT fees of $5,399.

(4)The majority of other expense (income) for Corporate and other is interest expense of $5,753.

-83-

For the years ended December 31, 2025, 2024 and 2023, two, four and three customers, respectively, made up greater than 10% of our total revenues.

NOTE 19—LEASES

The Company leases office space and other office equipment under operating lease arrangements (with initial terms greater than twelve months), expiring in various years through 2033. These leases have been entered into to better enable the Company to conduct business operations. Office space is leased to provide adequate workspace for all employees in Pittsburgh, Pennsylvania and Houston, Texas. Landfill site operating leases include gas monitoring devices that serve to improve production efficiencies and alert technicians to issues and safety concerns occurring at the well head. Office space, office equipment and gas monitoring equipment agreements that exceed 12 months are accounted for as operating leases in accordance with ASC 842, Leases.

The Company also leases safety equipment for the various operational sites in the United States. The term of certain equipment exceeds twelve months and is accordingly classified as a finance lease under ASC 842. The finance leases expire in 2026 and were entered into in order to provide a safe work environment for operational employees.

The Company determines if an arrangement is, or contains, a lease at inception based on whether that contract conveys the right to control the use of an identified asset in exchange for consideration for a period of time. For all operating and finance lease arrangements, the Company presents at the commencement date: a lease liability, which is a lessee’s obligation to make lease payments arising from a lease, measured on a discounted basis; and a right-of-use asset, which is an asset that represents the lessee’s right to use, or control the use of, a specified asset for the lease term.

The Company has elected, as a practical expedient, not to separate non-lease components from lease components, and instead account for each separate component as a single lease component for all lease arrangements, as lessee. In addition, the Company has elected, as a practical expedient, not to apply lease recognition requirements to short-term lease arrangements, generally those with a lease term of less than twelve months for all classes of underlying assets. In determination of the lease term, the Company considers the likelihood of lease renewal options and lease termination provisions.

The Company uses its incremental borrowing rate, as the basis to calculate the present value of future lease payments, at lease commencement. The incremental borrowing rate represents the rate of interest a lessee would have to pay to borrow an amount equal to the total lease payments on a collateralized basis over a similar term in a similar economic environment.

As of December 31, 2025, there were no leases entered into which have not yet commenced and that would entitle the Company to significant rights or create additional obligations. The total lease cost included in our consolidated financial statements of operations for the years ended December 31, 2025, 2024 and 2023 were $3,080, $859, and $695, respectively.

Leases with an initial term of 12 months or less are not recorded on the Consolidated Balance Sheet and the lease expense for those leases is recognized on a straight-line basis. The short-term lease expense for the years ended December 31, 2025, 2024 and 2023 were $3,711, $3,927 and $2,960, respectively.

-84-

Supplemental information related to operating lease arrangements was as follows as of and for the year ended December 31, 2025, 2024 and 2023:

Future minimum operating lease payments for the years ending December 31, are as follows:

Supplemental information related to finance lease arrangements was as follows:

Future minimum finance lease payments are as follows:

NOTE 20—COMMITMENTS AND CONTINGENCIES

Concentrations

A substantial portion of the Company’s revenues are generated from five locations in 2025, 2024, and 2023, each in separate areas of the country. For the years ended December 31, 2025, 2024 and 2023,68%,69% and 68%, respectively, of operating revenues were derived from these locations. In addition, five customers make up 77% and 76% of trade receivables as of December 31, 2025 and December 31, 2024, respectively.

Environmental

The Company is subject to a variety of environmental laws and regulations governing discharges to the air and water, as well as the handling, storage and disposing of hazardous or waste materials. The Company believes its operations currently comply in all material respects with all environmental laws and regulations applicable to its business. However, there can be no assurance that environmental requirements will not change in the future or that the Company will not incur significant costs to comply with such requirements.

-85-

Contingencies

The Company, from time to time, may be involved in litigation. At December 31, 2025, management does not believe there are any matters outstanding that would have a material adverse effect on the Company’s financial position or results of operations.

Note 21—INCOME PER SHARE

Basic and diluted income per share was computed using the following common share data for the years ended December 31, 2025, 2024 and 2023, respectively:

NOTE 22—SUBSEQUENT EVENTS

The Company evaluated subsequent events related to its December 31, 2025 consolidated financial statements through the date the financial statements were issued. The Company is not aware of any subsequent events which would require recognition or disclosure in the financial statements, except for the matters discussed below.

On March 9, 2026, the Company entered into a new, five year Senior Credit Facility with CCH1 MEH Lender LLC (a wholly owned subsidiary of Hannon Armstong Capital LLC “HASI”, “New Senior Credit Facility”) that consists of up to $200,000 in senior indebtedness, of which $155,000 is outstanding as of March 11, 2026. These proceeds were used to repay all outstanding debt of the Company at the date of closing. Subject to various requirements as defined in the underlying agreement, the Company expects to have an additional $25,000 in proceeds drawn upon the conclusion of an engineering review over its Montauk Ag Renewables Acquisition. Also subject to various requirements as defined in the underlying agreement, the Company expects the final proceeds to be dispensed at the commissioning and operation of its Montauk Ag Renewables Ag Acquisition. Finally, the Company maintains a cash collateralized facility with an entity not related to the HASI New Senior Credit Facility and still has issued $2,190 of letters of credit. The New Senior Credit Facility matures in March 2031. The New Senior Credit Facility includes various affirmative and negative covenants that require the Company to meet specified financial ratios and financial tests, as defined in the underlying agreement. Under the New Senior Credit Facility, the Company is required to maintain:

•

Total Net Leverage Ratio (as defined in the Senior Credit Facility) of note more than 4.00 to 1.00, and

•

As of the end of each fiscal quarter, a Fixed Charge Coverage Ratio (as defined in the Senior Credit Facility)of not less than 1.20 to 1.00; and

•

Various other financial covenants or mandatory prepayments (as defined in the Senior Credit Facility).

The New Senior Credit Facility is subject to customary events of default and contemplates that the Company would be in default if, for any fiscal quarter (x) the average monthly D3 RIN price is less than $1.00 per RIN and (y) the consolidated average quarterly trailing EBITDA over the previous four quarters is less than $10,000.

The New Senior Credit Facility has a 24 month availability period during which only interest is payable quarterly. After the availability period, the Company is required to make quarterly principal payments equal to 1.25% of the total outstanding principal. The interest rate of the Senior Credit Facility is 10.25%.

In accordance with ASC 470-10-45-12 through 45, the Company classified $2,733 of its debt as short term debt, net of debt issuance costs, and $126,000 as long term debt as of December 31, 2025, based on management’s intent and demonstrated ability to refinance such obligations on a long term basis through the execution of the New Senior Credit Facility prior to issuance of the financial statements. The execution of the New Senior Credit Facility is disclosed as a non-recognized subsequent event.

-86-