Montauk Renewables, Inc. (MNTK) Business

ITEM 1. BUSINESS.

Unless the context requires otherwise, references to “Montauk,” the “Company,” “we,” “us” or “our” refer to Montauk Renewables, Inc. and its consolidated subsidiaries. Additionally, amounts are in thousands unless indicated otherwise.

Overview

We are a renewable energy company specializing in the recovery and processing of biogas from landfills and other non-fossil fuel sources to beneficial use as a replacement to fossil fuels. We develop, own, and operate RNG projects, using proven technologies that supply renewable fuel into the transportation and electrical power sectors. We are one of the largest U.S. producers of RNG, having participated in the industry for over 30 years. We established our currently operating portfolio of eleven RNG and two Renewable Electricity projects and development projects through self-development, partnerships, and acquisitions that span seven states.

In January 2021, we closed the initial public offering of our common stock on the Nasdaq Capital Market with the shares traded under the symbol “MNTK.” Our common stock is also secondarily listed on the Johannesburg Stock Exchange under the trading symbol “MKR.”

Products Sold

The revenues Montauk receives from selling renewable energy consist of two main components. The first component consists of revenues from the commodity value of the natural gas or electricity generated, which we sell through a variety of term-length agreements. The second component consists of revenues from the Environmental Attributes derived from the production of RNG and Renewable Electricity.

Our current operating projects produce either RNG or Renewable Electricity by processing biogas from landfill sites or agricultural waste from livestock farms. Biogas is produced by microbes as they break down organic matter in the absence of oxygen (during a process called anaerobic digestion). Our two current sources of commercial scale biogas are LFG or ADG. We typically secure our biogas feedstock through long-term fuel supply agreements and property lease agreements with biogas site hosts. Once we secure long-term fuel supply rights, we design, build, own, and operate facilities that convert the biogas into RNG or use the processed biogas to produce Renewable Electricity. Once collected, biogas can be processed into pipeline-quality RNG or converted into electricity. The conversion facility is typically located on landfill property away from the active fill operations where additional waste is added to the landfill site. Because we are capturing waste methane and making use of a renewable source of energy, the RNG and Renewable Electricity we produce also generates valuable Environmental Attributes which we can monetize under federal and state renewable initiatives.

RNG

The RNG we process is pipeline-quality and can be used for transportation fuel when compressed or liquefied. Virtually all of the RNG we produce is used as a transportation fuel because this market generally provides the most value for our RNG production. CNG has been the most common fuel used by fleets where medium-duty trucks are close to the fueling station, such as city fleets, local delivery trucks and waste haulers. Additionally, landfill gas and gas from livestock digesters can be processed into pipeline-quality RNG by removing the majority of the non-methane components including carbon dioxide, water, sulfur, nitrogen, and other trace compounds.

RNG, like traditional natural gas, is traded nationally. Once in an interstate pipeline, RNG can be transported to vehicle fueling stations to be used as a transportation fuel, to utilities to generate power, or for use in generating fuel cell energy anywhere within the North American pipeline system. This flexibility enables us to capture value from the renewable attributes of biogas by delivering RNG to markets and customers that place a premium on renewable energy. Although RNG has the same chemical composition as natural gas from fossil sources, government incentive programs assign unique Environmental Attributes to it due to its origin from low-carbon, renewable sources, which we also monetize.

RNG is priced in-line with the wholesale natural gas market, based on Henry Hub pricing, with regional variation according to demand. We sell the RNG produced from our projects under a variety of short-term and medium-term agreements to counterparties, with tenures generally varying from three to five years. Our contracts with counterparties are typically structured to be based on varying natural gas price indices for the RNG produced. We also share a portion of our Environmental Attributes with certain pathway providers as consideration for the counterparty using our RNG as a transportation fuel.

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Renewable Electricity

Renewable electricity is generated using gas-fueled engines or turbine-driven electrical generators, which are designed to operate efficiently on medium-Btu gas. As such, electricity generation typically involves producing medium-Btu gas, which is then pumped into a generating facility. Electricity is a commodity that trades and is priced on a regional basis in and among regional control areas. Pricing for commodity-sold electricity can be based on day-ahead prices for scheduled deliveries or hourly, real-time prices for unscheduled deliveries. Prices vary across the country based on weather, load patterns and local or regional power and transmission restrictions. The Renewable Electricity produced at our biogas-to-electricity projects is sold under long-term contracts to creditworthy counterparties, typically under a fixed price with escalators. The terms of these contracts range up to 18 years, excluding renewal periods, with a weighted average remaining tenure of 16 years, based on 2025 electricity production.

Environmental Attributes

When used as a transportation fuel or to produce electricity, RNG can generate additional revenue streams through the generation and sale of Environmental Attributes under various programs, including the national renewable fuels standard and state-level California LCFS. The Environmental Attributes that we generate and sell are composed of RINs and LCFS credits, which are generated from the conversion of biogas to RNG that is used as a transportation fuel, as well as RECs generated from the conversion of biogas to Renewable Electricity. In addition to revenues generated from our product sales, we also generate revenues by providing various value-added services to certain of our biogas site partners. In 2025 and 2024, our projects generated approximately 4.6% and 6.2%, respectively, of all CNG and LNG D3 RINs in the United States. During 2021, we entered into an agreement to sell a portion of our production as a renewable component of refinery fuel exports into the European Union’s Renewable Energy Directive from certain RNG production facilities that have achieved International Sustainability & Carbon Certification registration. This diversification strategy accounted for approximately 0.9% of the reduction in generation of D3 RINs in 2025. We continue to sell a portion of our production as a renewable component of refinery fuel exports.

We seek to mitigate our exposure to commodity and Environmental Attribute pricing volatility. Through contractual arrangements with our site hosts and counterparties, we typically share pricing and production risks while retaining our ability to benefit from potential upside. A portion of the RNG volume we produce is sold under bundled fixed-price arrangements for the RNG and Environmental Attributes, some of which include a sharing arrangement where we benefit from prices above certain thresholds. For our remaining RNG projects, our partners may receive a cash payment instead of in-kind sharing arrangements where our partners receive the Environmental Attributes, thereby sharing in Environmental Attribute pricing risk.

On the electricity side of our business, all of our products and related Environmental Attributes are sold under fixed-price contracts with escalators, limiting our pricing risk. Finally, our contracts with site hosts often require payments to our site hosts in the form of royalties based on realized revenues, direct development contributions, or, in some select cases, based on production volumes.

D3 RINs

RNG has the same chemical composition as natural gas from fossil sources, but has unique Environmental Attributes assigned to it due to its origin from organic sources. These attributes qualify RNG as a renewable fuel under the federal RFS program, established pursuant to the EPACT 2005 and EISA, allowing RNG to generate renewable fuel credits called RINs when the RNG is used as a transportation fuel.

RINs are saleable regulatory credits that represent a quantity of qualifying fuel and are used by refiners and importers to evidence compliance with their RFS obligations. Given that the RFS is a national program, the price of a RIN is the same anywhere in the United States. The RFS program originally contemplated 1.75 billion gallons of fuel from cellulosic biofuels by 2014, the use of which would be tracked through D3 RINs. However, cellulosic biofuel production grew slower than expected and prompted the EPA to expand the definition of biofuels that could qualify for D3 RINs to include fuels from cellulosic biogas, including biogas from landfills, livestock farms, and WRRFs. This significantly increased the quantity of D3 RINs produced, with production increasing to approximately 33 million net RINs in 2014 and approximately 923 million net RINs in 2024. In addition, given the historic shortage in supply of D3 RINs to meet blending requirements, the EPA allows obligated refiners to satisfy RFS compliance obligations for D3 RINs by either purchasing CWC plus D5 RINs or by purchasing D3 RINs. CWC prices were set annually and were typically published by the EPA each November. Historically, the value of a D3 RIN is therefore a derivative of the market price for D5 RINs and CWCs, which in turn, are inversely linked to the wholesale price of gasoline. On July 12, 2023, the EPA issued final rules in the Federal Register which indicated that it will not be utilizing its cellulosic waiver authority to reduce cellulosic biofuel volume for 2023-2025, thus CWCs will not be available unless actual production is lower than the RVO. On December 5, 2024, the EPA proposed rules to partially waive the 2024 cellulosic biofuel volume requirement using the general waiver authority and revise the associated percentage standard under the RFS. This rule was finalized on July 7, 2025. The EPA made CWCs available for purchase under the final rule along with the partial waiver of the 2024 cellulosic biofuel volume requirement. The final rule also requires the use of a new data source for the average wholesale price of gasoline to be used in the calculation of the CWC price.

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The EPA proposed the 2026 and 2027 RVOs, and a Partial Waiver of the 2025 Cellulosic Biofuel Volume Requirement on June 17, 2025. On August 22, 2025, the EPA issued decisions on 175 Small Refinery Exemptions (SREs) for the years 2023-2025. EPA subsequently proposed a Supplemental Rule (referred to as the SRE reallocation volume) on September 18, 2025, which would account for the for 2023-2025 exempted RVOs. EPA co-proposed SRE reallocation volumes that would account for 100 percent or 50 percent of the exemptions granted for the 2023-2025 compliance years. EPA is aiming to finalize new biofuel mandates for 2025, 2026 and 2027 along with the Supplemental Rule in late March 2026.

We have been active in the RFS program since 2014 and expect to remain a significant contributor to the overall generation of RINs from RNG. We monetize our portion of the RINs, directly, at auction or through third-party agents or marketers.

CA LCFS

CA LCFS credits are environmental credits generated in California in order to stimulate the use of cleaner, low-carbon fuels. This program encourages the production of low-carbon fuels by setting annual CI standards, which are intended to reduce GHG emissions from the state’s transportation sector. One of the key aspects of the program is that it encourages the use of low-carbon transportation fuel, such as CNG, in vehicles instead of gasoline. This program further encourages use of renewable fuels in vehicles over CNG from fossil fuels.

The value of an CA LCFS credit varies according to the CI value of the fuel source as determined by CARB. Fuels that have a lower CI score benefit from a higher percentage of a CA LCFS credit. RNG from LFG and livestock digester biogas that are used as a transportation fuel both qualify for CA LCFS credits. The number of CA LCFS credits for RNG from livestock digesters is significantly higher than the number of CA LCFS credits for RNG from landfills, due to the relative CI scores of the two fuels. Fuel that is eligible for RINs can also receive CA LCFS credits. As a result, CA LCFS credits represent a revenue stream incremental to the value RNG producers receive for RINs. For livestock digester RNG projects, CA LCFS credits are a substantial revenue driver. We have one project that is currently approved and eligible to earn CA LCFS credits, which is a livestock digester RNG project. Because of the growth in the number of RNG projects developed in 2023-2025, the CA LCFS program has been saturated in credits. As a result, the lower CI score projects (e.g. livestock digester RNG projects) have the financial advantage of being accepted into the LCFS program. The revenue generated by CA LCFS credits will increase as we continue to develop dairy or livestock manure projects as long as construction on these type of projects is started before December 31, 2029. The LCFS program includes a targeted phase-out of all “avoided methane” credits for dairy and livestock manure projects by 2040.

On January 3, 2025, CARB submitted to the State of California Office of Administrative Law proposed amendments to the LCFS regulations. California’s amended LCFS regulations officially took effect on July 1, 2025, setting more aggressive carbon intensity reduction targets, 30% by 2030 and 90% by 2045.

Several states in the United States also have or are considering adopting this model. Oregon’s Clean Fuels Program, enacted in 2009 and implemented in 2016, operates using a credit system similar to the CA LCFS program. Washington’s Clean Fuel Standard was passed in 2021 and implemented in 2023 utilizing a similar credit system as Oregon and California. New Mexico’s Clean Fuel Standard was passed in 2024 with plans to finalize implementation in 2026. Similar to RINs, LCFS credits can be sold separately from the RNG fuel sold, allowing us to monetize LCFS credits for fuel produced and purchased outside of states that have LCFS programs.

RECs

The primary Environmental Attributes derived from the production of electricity from renewable resources are RECs, which translate into additional revenues for units of Renewable Electricity produced. Biogas is considered to be a renewable resource in all 37 states that encourage or mandate the use of renewable energy. Thirty states, the District of Columbia, and Puerto Rico have RPS that require utilities to supply a percentage of power from renewable resources, and seven states have a Renewable Portfolio Goal that is similar to RPS, but it is an objective or goal and not a requirement. Many states allow utilities to comply with RPS through tradable RECs, which provide an additional revenue stream to RNG projects that produce electricity from biogas.

The value of a REC is dependent on each state’s renewable energy requirements as mandated by its RPS. REC values are higher in states that require a percentage of total electricity to come from renewable resources. In states with no renewable energy requirements, RECs can have no value at all. In some markets, we have entered into PPAs under which we sell RECs bundled with the power being sold at a combined price. This occurs where the utility off-take counterparty offers a combined rate for the renewable energy it needs to satisfy RPS or other business requirements that is the best combined price for one of our projects.

Strategic Overview

Our business strategy focuses on the following three areas that we believe present the greatest growth opportunities for the Company at this time.

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Continued Expansion into Agricultural Feedstocks for RNG Production

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Optimize Existing Assets and Project Portfolio and Opportunistically Develop New Projects

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Valued-added Service Offerings

Continued Expansion into Agricultural Feedstocks for RNG Production

As part of our long-term strategy, we are focused on diversifying our project portfolio beyond LFG through expansion into additional methane producing assets, while opportunistically adding third-party developed technology capabilities to boost financial performance and our overall cost competitiveness. We are commercially operating our first agricultural waste project (dairy manure), actively pursuing new fuel supply opportunities in WRRFs, and looking at long-term organic waste and sludge opportunities for the generation of biogas.

We view dairy farms and other forms of organic agricultural waste as a significant opportunity for us to expand our RNG business, as processing biogas from dairy farms and from other forms of organic agricultural waste requires similar expertise and capabilities as processing biogas from landfills. Many of the existing biogas processing in these industries is for electricity production, which creates additional opportunities for acquisition and conversion to higher-value RNG facilities.

Pico Facility

We undertook an agricultural project when we closed on the acquisition of Pico, the anaerobic digester and two Jenbacher engines at the Bettencourt dairy farm in Jerome, Idaho in September 2018. The project sources manure from a dairy farm with up to approximately 18,500 milking cows. While Pico was initially a Renewable Electricity site, we brought an RNG facility at that location online in 2020. The facility sells transportation fuel into the California transportation market. The collection of the fuel supply is potentially easier at dairy farms than at landfills due to higher quality, more uniform feedstock, and potentially less volatility in inlet gas and biogas collection in a more controlled environment. During the second quarter of 2021, we amended our Pico feedstock agreement (“Pico Feedstock Amendment”). The amendment increased the amount of feedstock supplied to the facility for processing over a four-year period.

As part of our overall capacity expansion at the Pico facility, in 2021 and 2024, we undertook significant efforts to improve the performance of the existing digestion process at our Pico facility. We temporarily idled RNG production at this facility in order to clean out settled solids in the digester, replace the cover of the digester, and make various other efficiency improvements. The dairy began delivering the first and second increases in feedstock during the third quarter of 2022 and we have made two payments to the dairy as required in the Pico Feedstock Amendment. The improved efficiencies of our existing digestion process and the water management improvements have enabled us to process the increased feedstock volumes. We completed the design of the digestion capacity expansion project in 2022, commenced construction of the digestion expansion, and commissioned the digestion expansion project in 2024. In 2025, we made the final payment to the dairy as required under the Pico Feedstock Amendment and the dairy began delivering the final increase in feedstock volumes.

CARB finalized in the first quarter of 2023 Pico's initial CI Score Pathway model. We have been recognizing revenues from RINs and LCFS credits since the fourth quarter of 2022.

As a result of the 2025 Annual Fuel Pathway Report ("AFPR") review, our CI score worsened. The worsening CI score is primarily due to increased biogas upgrading and fugitive emissions from the biogas upgrading process. We are currently conducting an analysis to determine the benefit of installing a combustion device to eliminate fugitive emissions. As a result of this, we may be subject to a claw back of LCFS credits related to the overgeneration of LCFS credits using the old CI Score. While we do not believe the penalty applies to us, the legislation does allow for a penalty of four times the number of LCFS credits to be taken away from a producer as a penalty if its score is lowered. As a result, the number of LCFS credits for RNG generated at our dairy farm project will decline.

Montauk Ag Renewables

In 2021, Montauk Ag Renewables purchased technology and assets (the “Montauk Ag Renewables Acquisition”) to recover residual natural resources from swine waste and to refine and recycle such waste products through proprietary and other processes to produce high quality renewable natural gas, renewable electricity, North Carolina swine RECs and micronutrient organic fertilizer alternatives. Upon completion of the first phase of the project, we expect that it will annually produce 41 MWh of electric power, approximately 120 RECs and 870 tons of organic fertilizer alternative. We have entered into a ten-year agreement to sell all of the renewable electricity generated by the project. Furthermore, we have signed a REC agreement with Duke Energy for 47 RECs. We currently expect the first phase capital investment to be approximately $200,000 and have spent approximately $140,000 as of December 31, 2025. We expect our production and revenue generation activities to commence in April 2026.

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Other Opportunities

Other industries that present opportunities of scale for biogas conversion include swine farms and WRRFs. Biogas production from swine farms is a nascent biogas industry with great growth potential because swine manure is the second largest source of manure methane from livestock and only a small percentage of farms currently have biogas conversion capabilities. Additionally, while a larger percentage of WRRFs have biogas processing facilities, many process biogas for electricity production creating additional opportunities for acquisition and conversion to RNG facilities. As with LFG and dairy farms, biogas from both swine farms and WRRFs qualify for D3 RINs under the RFS program. We believe our demonstrated versatility to operate processing facilities using multiple fuel supply sources will give us a competitive advantage in these markets relative to other new entrants who have only demonstrated capabilities with one fuel supply source. The drive toward voluntary and most likely regulatory-required organic waste diversion from landfills is of particular interest as we leverage our current experience base. As our biogas processing technology continues to improve and the required energy intensity of the RNG and Renewable Electricity production process is reduced, we expect that we will be able to enter new markets for our products.

Optimize Existing Assets and Project Portfolio and Opportunistically Develop New Projects

Expanding Operations at Existing Project Sites. We monitor biogas supply availability across our portfolio and seek to maximize production at existing projects by expanding operations when economically feasible. Most of our landfill locations continue to accept waste deliveries and the available LFG at these sites is expected to increase over time, which we expect to support expanded production. In 2025, this has allowed us to maintain average production availability of approximately 89% at our RNG projects and 92% at our Renewable Electricity projects.

We treat our existing assets as an integrated portfolio rather than a collection of individual projects. This allows us to utilize any new business practices or technologies across our entire project portfolio quickly, including advances with respect to troubleshooting, optimization, cost savings, and host site interaction. Our integrated, pro-active and value-add approach helps us maintain strong relationships with our partners, which we seek to leverage to optimize the performance of our existing projects.

In addition to monitoring biogas supply, we are incorporating similar collection and processing used for our biogas supply to our byproduct streams to capture, clean, and liquefy biogenic carbon dioxide at our existing projects. In 2024, we announced our first agreement for certain of our Texas facilities related to biogenic carbon dioxide collection.

We also experience organic growth in production at our existing projects as a result of increases in biogas supply at our projects and on-going optimization initiatives. We size our projects to account for this increase in the biogas supply curve over time. For example, at many of our newer projects, such as Apex and Galveston, we expect gradual increases in production as those landfill sites continue to grow. Additionally, many of our capacity expansion efforts to date, such as those at McCarty, Rumpke, and Pico, have helped to optimize our project capacity to take advantage of excess biogas at older landfills that are still open and growing. Not only have our projects achieved an initial increase in production following the capacity expansion project, but we also expect to see continued gradual increases in production over time.

Converting Existing Renewable Electricity Projects to RNG. We periodically evaluate opportunities to convert existing projects from electricity generation to RNG production. These opportunities tend to be attractive for our merchant electricity projects given the favorable economics for RNG plus RIN sales relative to merchant electricity rates plus REC sales. To date, we have converted two projects from LFG-to-electricity to LFG-to-RNG and a third project from ADG-to-electricity to ADG-to-RNG. We will continue to explore the feasibility of other opportunities across our remaining Renewable Electricity portfolio.

Opportunistic Development of New RNG Projects. We apply a financially disciplined model toward new project development that considers the relative risk of a given project and associated feedstock costs, offtake contracts and any other related Environmental Attributes that can be monetized. We are currently developing two project expansion opportunities at existing project sites and one project at a new project site. We regularly analyze potential new projects that are at various stages of negotiation, engineering design and financial review. The potential projects typically include a mix of new project sites and strategic acquisitions. Currently, no new potential projects are subject to definitive agreements and each potential opportunity is subject to competitive market conditions.

Developing LFG to Renewable Electricity Projects. We continue to analyze for future development to include sites from which we would generate renewable electricity. This evaluation of potential new renewable electricity projects would be reviewed with the same financially disciplined model we use to evaluate new LFG-to-RNG projects.

The RNG industry remains highly fragmented. We believe continued industry fragmentation presents an opportunity for further industry consolidation. We are well-positioned to take advantage of this consolidation opportunity because of our scale, operational and managerial capabilities, and execution track record in integrating acquisitions. Over the last ten years, we have acquired 13

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projects and members of our current management team have led all of those acquisitions. We expect that as we continue to scale up our business, our increased size, capabilities and access to capital will provide us with increased strategic acquisition opportunities.

Valued-Added Service Offerings

Over our three decades of experience, we have developed the full range of RNG project related capabilities from engineering, construction, management and operations, through EHS oversight and Environmental Attributes management. By vertically integrating across RNG services, we are able to reduce development and operations costs, optimize efficiencies and improve operations. Our full suite of capabilities allows us to serve a multi-project partner for certain project hosts across multiple transactions, including through strategic transactions. To that end, we actively identify and evaluate opportunities to acquire entities that will further our vertically-integrated services.

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Our Current Operating Portfolio

We currently own and operate 13 projects, 11 of which are RNG projects and two of which are Renewable Electricity projects. We are currently in the process of expanding two RNG projects from LFG. We are also working on other projects which will repurpose equipment from existing biogas facilities for use at new project sites. The below graphic does not include the Montauk Ag project, which is currently under development.

(1)
“COD” refers to the commercial operation date of each site.

(2)
This is equivalent to the project’s design capacity and assumes inlet methane content of 56% for all sites other than Pico, which assumes inlet methane content of 62%, and process efficiency of 91%.

(3)
All of our landfill sites are accepting waste except our Shade site. Our Shade site is closed to accepting new waste, but is currently expected to continue to generate a commercial level of RNG for an additional ten years. Our operating RNG projects have an average expected remaining useful life of approximately 17 years.

We have a long history of operating our projects with partners, with our oldest relationship going back nearly 50 years. On average, we have had an approximate 20-year history with our current project site owners. As of December 31, 2025, our operating RNG projects have an average expected remaining useful life of approximately 17 years and our operating Renewable Electricity projects have an average expected remaining useful life of approximately 33 years, including renewal periods.

Approximately 63% of our 2025 RNG production has been monetized under fuel supply agreements with expiration dates more than 15 years from December 31, 2025. Approximately 94% of our 2025 Renewable Electricity production has been monetized under fuel supply agreements with expiration dates more than 15 years from December 31, 2025. Concurrent with our fuel supply agreements, we typically enter into property leases with our project hosts, which govern access rights, permitted activities, easements and other property rights. We own all equipment and facilities on each leased property, other than equipment provided by utility companies providing services on-site. Lease termination typically requires the restoration of the leased area to its original condition. We have successfully ended leases on six of our former facilities.

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Our RNG projects currently utilize three of the four proven commercial technologies available to process raw biogas into RNG, including: pressure swing absorption (“PSA”), Membrane Filtration and solvent scrubbing. We are capable of working with virtually all available biogas processing technologies at our sites. We attend industry conferences and maintain an ongoing dialogue with key equipment providers to ensure we stay informed of the latest technology that could be deployed at our current and future facilities.

Stated capacity reflects the design capacity of each facility. Several of our projects have reserve capacity when comparing design capacity to available biogas feedstock. Several previous acquisitions are gas limited and therefore do not operate at their design capacity. Our larger projects have expansions planned or are being evaluated for future expansions dependent on the availability of excess biogas feedstock.

RNG Projects

We currently own and operate 11 RNG projects across four states: Ohio (two), Pennsylvania (four), Texas (four) and Idaho (one) which, in the aggregate, have a total design capacity of approximately 35,9522 MMBtu/day.

RNG Projects

(1) Includes the capacity for our second Apex Facility, which was commissioned in 2025.

* Assumes inlet methane content of 56% for all sites other than Pico, which assumes inlet methane content of 62%, and process efficiency of 91%.

Renewable Electricity Projects

We currently own and operate the following two Renewable Electricity projects in California and Oklahoma, which, in the aggregate, have a total design capacity of approximately 29.1 MW. Our Renewable Electricity projects utilize reciprocating engine generator sets to generate electricity at landfills. This does not include the Montauk Ag Renewables project in North Carolina, which is not yet operational.

Renewable Electricity Projects

(1)
Beginning in October 2020, we began reporting the result of operations of Pico within RNG, but Pico continues to generate electricity.

* Assumes inlet methane content of 56% and process efficiency of 91%,

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A critical component of our business is our ability to negotiate and maintain long-term fuel supply agreements at our project sites. We have developed strong working relationships with our landfill site owners, including eight of 13 operating projects and other potential development projects each with Waste Management and Republic Services, the two largest waste companies in the United States, and actively seek to strategically extend our tenure at our project sites.

Our projects provide our landfill and agricultural partners a solution to monetize biogas from their sites, support their regulatory compliance and provide them with environmental services. We have had working relationships with Republic Services since 1986 and with Waste Management since 2004 and we enable monetization of their biogas while maintaining regulatory compliance. We seek to differentiate ourselves from our competitors through our extensive experience across a variety of commercialized beneficial uses of processed biogas, including pipeline-quality natural gas, power generation and boiler fuel gas products. To date, we have not had any fuel supply agreement terminated by any site partner once we have established a facility on the site, which we believe serves as evidence of our operational expertise, reliability and consistent value delivered to our site partners. The table below is a summary of the expiration periods of those agreements. We are consistently reviewing and pursuing extensions for all of our fuel supply agreements well before their expirations and for future agreements, we continue to target contracts with expirations of 20 years from commencement of operation with options for extension.

Fuel Supply Agreement Summary

RNG Projects

Renewable Electricity Projects

(1)
Our Pico project continues to generate both RNG and Renewable Electricity and is accounted for above in the RNG Projects summary.

Customers

Our customers for RNG and RINs typically include large, long-term owner-operators of landfills and livestock farms, local utilities, and large refiners in the natural gas and refining sectors. Royalty structures included in our agreements, as well as the large size of our counterparties, limit their credit risk. Valero and Exxon represented approximately 17.4% and 11.3%, respectively, of our operating revenues in 2025 from the sale of Environmental Attributes. We sell RINs to numerous RIN off-take parties and our largest RIN off-taker as a percentage of revenue can vary year to year given the short-term nature of these contracts. In addition to revenues from sales of RNG and RINs, we also share a portion of our Environmental Attributes with our pathway providers as in-kind consideration for the counterparty using our RNG as a transportation fuel.

Our customers for electricity typically include investor-owned and municipal electricity utilities. For the sale of Renewable Electricity and RECs, the City of Anaheim represented approximately 9.3% of our operating revenues in 2025. These sales occurred under a PPA between us and the City of Anaheim, in which electricity and RECs are sold at fixed prices. In 2025, we converted 100% of the monetization of our Renewable Electricity production and Environmental Attributes under fixed-price agreements. For our electricity sales, all of our customers with whom we have off-take agreements are investment-grade entities with low credit risk.

No other single customer represented more than 10% of our total 2025 operating revenues.

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Suppliers and Equipment Vendors

The major technologies used by our projects for gas processing include solvent scrubbing PSA and membrane separation. For electricity generation, we use reciprocating engines. This affords Montauk experience with substantially all major vendors in the sector, and technical expertise in numerous technologies.

We source equipment from a variety of major suppliers with specialties in each technology. We enter into written ordinary-course agreements with suppliers to obtain industry-standard equipment for use in our operations. The contracts generally do not include any intellectual property rights other than for the intended use of the equipment. Membrane separation equipment is primarily provided by UOP and Air Liquide. PSA equipment is primarily provided by Xebec, Guild, Air Products, and BioFerm. Solvent scrubbing is primarily provided by Selexol. RNG ancillary constituent removal is done using equipment provided by Iron Sponge, MV Technologies, Thiopaq, Guild Associates, and PSB Industries. Electricity generation equipment is provided by Solar Turbines, Caterpillar, and Jenbacher.

In 2025, we made a substantial investment in a centralized Enterprise Resource Planning (“ERP”) system Microsoft Dynamics 365. It allows us to better integrate operations across our projects. This system centralizes maintenance operations across all of our projects. Our proactive approach to maintenance, corrective maintenance, root cause analysis, failure reporting, project management, and budgeting are all completed using the ERP system.

Competition

There are several other companies operating in the renewable energy and waste-to-energy space, ranging from other project developers to service or equipment providers.

Our primary competition is from other companies or solutions for access to biogas from waste. Evolving consumer preferences, regulatory conditions, ongoing waste industry trends, and project economics have a strong effect on the competitive landscape and our relative ability to continue to generate revenues and cash flows. We believe that our status as one of the largest operators of LFG-to-RNG projects, our 30-year track record of operating and developing projects, and our deep relationships with some of the largest landfill owners and dairy farms in the country position us very well to continue to operate and grow our portfolio, and respond to competitive pressures. We have demonstrated a track record of strategic flexibility across our 30-year history which has allowed us to pivot towards projects and markets that we believe deliver optimal returns and stockholder value in response to changes in market, regulatory and competitive pressures.

The biogas market is highly fragmented. We believe our size relative to many other LFG companies and our capital structure puts us in a strong position to compete for new project development opportunities or acquisitions of existing projects. However, competition for such opportunities, including the prices being offered for fuel supply, will impact the expected profitability of projects to us, and may make projects unsuitable to pursue. Likewise, prices being offered by our competitors for fuel supply may increase the royalty rates that we pay under our fuel supply agreements when such agreements expire and need to be renewed or when expansion opportunities present themselves at the landfills where our projects currently operate. It is also possible that more landfill owners may seek to install their own LFG projects on their sites, which would reduce the number of opportunities for us to develop new projects. Our overall size, reputation, access to capital, experience and decades of proven execution on LFG project development and operation leave us well-positioned to compete with other companies in our industry.

We are aware of several competitors in the United States that have a similar business model to our own, including Clean Energy Fuels Corp, Opal Fuels, U.S. Gain, Brightmark, Gevo Inc., and AMP Energy, as well as companies with biogas-to-energy facilities as a segment or subsidiary of their operations, including DTE, Ameresco, and British Petroleum (bp, acquired Archaea Energy in 2022). In addition, certain landfill operators, such as Waste Management, have also chosen to selectively pursue biogas conversion projects at their sites. Finally, Republic has entered into a joint venture with bp (formerly through Archaea Energy) to develop certain of its LFG locations.

Government Regulation

Our projects are subject to a range of federal, state and local environmental, health and safety laws and regulations, depending on the nature and configuration of the project, as well as where the project is located. We have established processes and procedures to comply with laws and regulations applicable to our operations, and have partnered with external experts, as needed, to meet applicable compliance requirements. As a renewable energy company, we are committed to being good stewards of the environment and to positively impacting the communities in which we operate.

All of our current Renewable Electricity projects are QFs. As a result, the facilities are exempt from rate regulation under Sections 205 and 206 of the Federal Power Act. We are required to document the QF status of each of our facilities in applications or self-certifications filed with FERC, which typically require disclosure of upstream facility ownership, fuel and size characteristics,

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power sales, interconnection matters, and related technical disclosures. Failure to maintain QF status may subject the project to additional regulatory requirements and may require the payment of refunds to customers and other costs or penalties.

We are subject to the Clean Air Act, which regulates the emissions of air pollutants to protect the environmental and public health. The combustion of biogas results in emissions of carbon monoxide, oxides of nitrogen, sulfur dioxide, volatile organic compounds and particulate matter. Federal, state and local laws may require us to obtain permits or impose other burdens, including monitoring, testing, recordkeeping and reporting by us in order for us to conduct operations. In addition, our operations and the operations of landfills may be subject to additional air emissions laws and regulations, such as those designed to address the emission of methane, a potent GHG.

Among other laws, we are subject to Subtitle D of the Resource Conservation and Recovery Act and other federal, state and local laws, which impose conditions on the handling of hazardous and non-hazardous waste, including the emission of methane in landfills. Likewise, we are subject to the Comprehensive Environmental Response Compensation and Liability Act of 1980 and other federal, state and local laws, which govern the investigation and cleanup of sites contaminated with hazardous substances. We have not been identified as a potentially responsible party with respect to environmental remedial costs at any site to date. We also may be required to obtain permits to discharge wastewater and stormwater pursuant to the Clean Water Act’s National Pollutant Discharge Elimination System and other federal, state and local laws governing such discharges.

Our RNG projects are subject to federal RFS program regulations, including the Energy Policy Act of 2005 and the Energy Independence and Security Act. The EPA administers the RFS program with volume requirements for several categories of renewable fuels. The EPA’s RFS regulations establish rules for fuel supplied and administer the RIN system for compliance, trading credits and rules for waivers. The EPA calculates a blending standard for each year based on estimates of gasoline usage from the Department of Energy’s Energy Information Agency. Separate quotas and blending requirements are determined for cellulosic biofuels, BBD, advanced biofuels and total renewable fuel. Further, we are required to register each RNG project with the EPA and relevant state regulatory agencies.

We qualify our RINs through a voluntary Quality Assurance Plan, which typically takes from three to five months from first injection of RNG into the commercial pipeline system. Further, we typically make a large investment in the project prior to receiving the regulatory approval and RIN qualification. In addition to registering each RNG project, we are subject to quarterly audits under the Quality Assurance Plan of our projects to validate our qualification.

Our RNG projects are also subject to state renewable fuel standard regulations. The CA LCFS program requires producers of petroleum-based fuels to reduce the CI of their products, beginning with a quarter of a percent in 2011, a 10% total reduction in 2020, and a 30% total reduction in 2030. Petroleum importers, refiners and wholesalers can either develop their own low-carbon fuel products, or buy CA LCFS credits from other companies that develop and sell low-carbon alternative fuels, such as biofuels, electricity, natural gas or hydrogen. We are subject to a qualification process for CA LCFS credits that is similar to that for RINs, including verification of CI levels and other requirements.

Our RNG projects are also impacted by state and federal gas quality standards. State regulators determine whether RNG may be purchased by the state’s local gas utilities, and whether a site operator may directly sell gas to a retail, or direct end-use, customer. FERC regulates the natural gas pipelines that transport gas in interstate commerce, and specifies or approves a gas pipeline’s tariff that sets the rates, terms and conditions, gas quality, and other requirements applicable to transportation of natural gas on the pipelines, including shipping RNG. Our sites are not permitted, and may not be physically able, to deliver RNG to a FERC regulated pipeline unless the pipeline’s receipt of the gas is consistent with the standards adopted in the pipeline’s FERC tariff. RNG-related gas quality standards may vary by pipeline and may be revised at any time, subject to all required regulatory approvals. We routinely test the RNG produced at our facilities in order to ensure compliance with applicable pipeline gas quality standards.

We monitor regulatory trends and developments in the U.S. regarding the regulation of greenhouse gas emissions. The EPA published final regulations for methane emissions, a greenhouse gas, from oil and gas facilities in March 2024. The regulation does not apply to our operations and could, combined with another public policy and private sector initiatives, increase interest in developing more renewable energy projects in the U.S. We will continue to monitor greenhouse gas regulatory initiatives in the U.S. and assess their potential relevance to our business and operations.

We routinely conduct compliance audits on our projects to proactively identify and correct potential compliance deficiencies or risks. Additionally, we closely monitor emerging regulatory developments that may impact our operations or business strategy. Montauk also participates in industry trade groups, such as the RNG Coalition and American Biogas Council, to advocate policies and regulatory frameworks that support continued expansion of renewable energy in the United States.

The operation of our business may expose us to certain liabilities and compliance costs related to environmental matters. These liabilities or compliance costs did not have a material effect on our capital expenditures or competitive position for fiscal 2024, nor do

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we expect them to have a material effect in the future. We believe we are in material compliance with all environmental regulations applicable to our operations.

Tax Regulation. The Inflation Reduction Act ("IRA" or the "Act") will be administered by multiple federal agencies including EPA, U.S. Department of Energy and the Internal Revenue Service of the U.S. Department of the Treasury. The goals of the IRA include incentivizing the development and production of renewable energy. We cannot speculate on exactly how the IRA will be implemented; however, the Act does contain numerous incentives for the production of clean energy which may impact our products. President Trump signed Executive Order 14154 in January 2025, which immediately paused the disbursement of funds under the IRA. The funding pause has been challenged by several states and the District of Columbia. The One Big Beautiful Bill Act was signed into law in July 2025 and, while we are still analyzing its potential impacts, we do not think that it will materially impact us.

Employees and Human Capital Resources

Employee Profile

We employed 189 people on December 31, 2025, located in California, Idaho, Ohio, Oklahoma, Pennsylvania, North Carolina and Texas. Our employee population is comprised of a mix of field operations personnel and office-based professionals. As of December 31, 2025, none of our employees were represented by a collective bargaining unit or labor union. We consider our employee relations to be good across our organization.

Health and Safety

Safety, including the health of our employees, is one of our core values and a priority across our operations. We are committed to developing a strong health and safety culture that reduces injuries and illness whenever possible. Our health and safety strategy is designed to proactively identify, mitigate and eliminate conditions that could result in serious injury or fatality. We also routinely train our employees on health and safety practices applicable to their job function and provide them all necessary personal protective equipment to perform their job in a safe manner.

Our recordable cases and total recordable incident rate (“TRIR”), excluding COVID-19 related incidents, was 1.06 and 2.89 in 2025 and 2024, respectively. The 2024 TRIR national average was 2.4 for all industries. We continue to focus on practices and measures to lower our TRIR.

Employee Development and Training

The success and growth of our business is significantly correlated with our ability to recruit, train, promote and retain talented individuals at all levels of our organization. To succeed in a competitive labor market, we have developed and implemented various recruitment and retention strategies. These include competitive salary structures, bonus programs and competitive benefits, as well as paid time off, sick leave, disability coverage, group term life insurance, and a retirement savings program. We also offer our employees tuition reimbursement for job-related education and training opportunities. We continue to provide leadership and developmental training for our executive, director and manager level employees.

Intellectual Property

We rely on a combination of patent, trademark, copyright and trade secret laws, employee and third-party nondisclosure/confidentiality agreements and non-compete and license agreements to protect our intellectual property. We acquired certain technology in the Montauk Ag Renewables Acquisition for which we received a patent during 2021 with a term of 20 years. In 2022, we filed a provisional patent application pertaining to a combustion-based oxygen removal condensate neutralization technology we developed. The provisional patent covers a new low pH neutralization technology designed to mitigate unfavorable pH condensate that is produced when wastewater is removed from the biogas conversion process. In 2024, we filed a provisional patent application pertaining to a renewable natural gas processing skid that we developed. In 2025, we filed a provisional patent application pertaining to a mobile swine waste separation, collection and removal apparatus and method as well as a provisional patent application for a mixing and solids removal system that we developed for our manure digester in Jerome, Idaho. Further, GreenWave Energy Partners, LLC (“GreenWave”), of which we own 51%, has a provisional patent application filed in 2025 for dispensing of RNG through expanded Transportation Fuel uses under the RFS.

Segments and Geographic Information

We have two operating segments: Renewable Natural Gas and Renewable Electricity Generation. For information regarding revenues and other information regarding our results of operations for each of our last two financial years, please refer to our financial

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statements included in this report and within “Item 7.—Management’s Discussion and Analysis of Financial Condition and Results of Operations” of this report.

Corporate Information

Montauk Renewables, Inc. is incorporated in the State of Delaware. Our principal executive offices are located at 5313 Campbells Run Road, Suite 200, Pittsburgh, PA 15205. Our telephone number is (412) 747-8700.

We are required to file annual, quarterly and current reports, proxy statements and other information with the SEC. The SEC maintains an Internet site that contains reports, proxy and information statements, and other information regarding issuers that file electronically with the SEC at http://www.sec.gov.

We also make financial information, news releases and other information available on our corporate investor relations website at www.ir.montaukrenewables.com. Our annual reports on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K, and any amendments to those reports filed or furnished pursuant to Section 13(a) or 15(d) of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), are available free of charge on this website as soon as reasonably practicable after we file these reports and amendments with, or furnish them to, the SEC. The information contained on or connected to our website is not incorporated by reference into this Annual Report on Form 10-K and should not be considered part of this or any other report filed with the SEC.

We are an “emerging growth company” as defined in the Jumpstart Our Business Startups Act of 2012. As an emerging growth company, we may take advantage of certain reduced reporting requirements that are otherwise applicable generally to public companies. We currently intend to take advantage of several of these reduced reporting requirements, including the extended transition periods for complying with new or revised accounting standards. See “Item 1A. Risk Factors—Emerging Growth Company Risks” for certain risks related to our status as an emerging growth company.

We are a “controlled company” within the meaning of the Nasdaq Stock Market LLC (“Nasdaq”) corporate governance standards. Certain stockholders, which are affiliates of two of our directors, Mr. John A. Copelyn and Theventheran G. Govender, own approximately 52.3% of our common stock and have entered into a Consortium Agreement (the “Consortium Agreement”) whereby the parties thereto will agree to act in concert with respect to voting our common stock, including in the election of directors, among other matters. As a controlled company, we may elect not to comply with certain Nasdaq corporate governance standards. See “Item 1A. Risk Factors—Common Stock Risks” for certain risks related to our status as a controlled company.

This report includes estimates, projections, and other information concerning our industry and market data, including data regarding the estimated size of the market, projected growth rates, and perceptions and preferences of consumers. We obtained this data from industry sources, third-party studies, including market analyses and reports, and internal company surveys. Industry sources generally state that the information contained therein has been obtained from sources believed to be reliable. Although we are responsible for all of the disclosure contained in this report, and we believe the industry and market data to be reliable as of the date of this report, this information could prove to be inaccurate.

Information About Our Executive Officers

Below is a list of the names, ages, and positions of our executive officers, and a brief summary of the business experience of our executive officers (ages as of March 1, 2026).

Sean F. McClain. Mr. McClain has served as our President and Chief Executive Officer and a member of our Board of Directors since January 2021. Prior to the Reorganization Transactions, Mr. McClain served as President and Chief Executive Officer of Montauk Holdings USA and as a member of its Board of Directors. From April 2011 until September 2019, Mr. McClain served as Chief Financial Officer of Montauk Holdings USA and Montauk Energy Holdings. Prior to joining Montauk in 2011, he held various management positions with BPL Global Limited, Bayer and Dick’s Sporting Goods and was in public accounting at Arthur Andersen LLP. He is a certified public accountant and has over 25 years of business and financial management experience.

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Kevin A. Van Asdalan. Mr. Van Asdalan has served as our Chief Financial Officer and Treasurer since January 2021. Prior to the Reorganization Transactions, Mr. Van Asdalan served as Chief Financial Officer of Montauk Holdings USA and as a member of its Board of Directors. From March 2018 until September 2019, Mr. Van Asdalan served as Controller of Montauk Energy Holdings and Montauk Holdings USA. Prior to joining Montauk in 2018, Mr. Van Asdalan served as a lines of business controller and manager of external reporting at L.B. Foster Company, a manufacturer, distributor and service provider for transportation and energy infrastructure, from July 2011 to March 2018. Prior to L.B. Foster, Mr. Van Asdalan held senior associate accounting positions at PricewaterhouseCoopers LLP and Sisterson & Co LLP. He is a certified public accountant and chartered global management accountant with nearly 25 years of business and financial management experience and holds a Master of Business Administration from the University of Pittsburgh Katz Graduate School of Business.

James A. Shaw. Mr. Shaw has served as our Chief Operating Officer since October 2025. He served as our Vice President of Operations from January 2021 until September 2025 and as the Vice President of Operations of Montauk Energy Holdings from September 2019 until December 2020. He previously served as North Region Manager of Montauk Energy Holdings from May 2016 until September 2019 and held positions of increasing responsibility as a site manager from 2010 until 2016. Prior to joining Montauk, Mr. Shaw was a facility manager for SONY Electronics at the world’s first vertically integrated television manufacturing facilities. Mr. Shaw has more than 25 years of experience in facilities operations and management.

John Ciroli. Mr. Ciroli has served as our Chief Legal Officer since January 2023. He served as our Vice President, General Counsel and Secretary from January 2021 until January 2023 and in the same role with Montauk Energy Holdings upon joining in July 2020. From July 2016 to July 2020, Mr. Ciroli was the North American Counsel and HR Manager for the North American subsidiaries of FAAC Group, a company that designs solutions for pedestrian and vehicle needs, representing the entities in their American and Canadian portfolio. From 2014 to July 2016, Mr. Ciroli was a Senior Litigation Counsel with the Housing Authority of the City of Pittsburgh. Mr. Ciroli has over 25 years of experience representing and advising domestic and international corporations and government entities in the areas of contracts, mergers and acquisitions, litigation, employment and governmental procurement and regulatory affairs. He was also a professor for Concord Law School, now Purdue Global, in the areas of Contracts, Constitutional Law, Torts and Evidence and is a member of the Pennsylvania State Bar and the bar of the U.S. Supreme Court.

Sharon Frank. Ms. Frank has served as our Vice President of Environmental, Health and Safety since October 2021. She served as our Director of Environmental, Health and Safety from April 2020 until October 2021 and as Manager of Environmental Compliance from June 2007 until April 2020. Prior to joining Montauk, from 2000 to 2007, Ms. Frank was Manager of Environmental Affairs for Duquesne Light Company’s unregulated business group. Ms. Frank has over 30 years of regulatory and environmental compliance experience.

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