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Form 8-K

sec.gov

8-K — Montauk Renewables, Inc.

Accession: 0001193125-26-335293

Filed: 2026-08-05

Period: 2026-08-05

CIK: 0001826600

SIC: 4932 (GAS & OTHER SERVICES COMBINED)

Item: Results of Operations and Financial Condition

Item: Financial Statements and Exhibits

Documents

8-K — mntk-20260805.htm (Primary)

EX-99.1 (mntk-ex99_1.htm)

XML — IDEA: XBRL DOCUMENT (R1.htm)

8-K

8-K (Primary)

Filename: mntk-20260805.htm · Sequence: 1

8-K

0001826600false00018266002026-08-052026-08-05

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): August 05, 2026

Montauk Renewables, Inc.

(Exact name of Registrant as Specified in Its Charter)

Delaware

001-39919

85-3189583

(State or Other Jurisdiction

of Incorporation)

(Commission File Number)

(IRS Employer

Identification No.)

5313 Campbells Run Road

Suite 200

Pittsburgh, Pennsylvania

15205

(Address of Principal Executive Offices)

(Zip Code)

Registrant’s Telephone Number, Including Area Code: (412) 747-8700

(Former Name or Former Address, if Changed Since Last Report)

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

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

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

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

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

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

Title of each class

Trading

Symbol(s)

Name of each exchange on which registered

Common Stock, par value $0.01 per share

MNTK

The Nasdaq Stock Market

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§ 230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§ 240.12b-2 of this chapter).

Emerging growth company ☒

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Item 2.02 Results of Operations and Financial Condition.

On August 5, 2026, Montauk Renewables, Inc. issued a press release announcing its financial results for the quarter ended June 30, 2026. A copy of the press release is furnished as Exhibit 99.1 to this report.

In accordance with General Instruction B.2 of Form 8-K, the information in Item 2.02 of this Current Report on Form 8-K, including Exhibit 99.1, shall not be deemed to be “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liability of that section, and shall not be incorporated by reference into any registration statement or other document filed under the Securities Act of 1933, as amended, or the Exchange Act, except as shall be expressly set forth by specific reference in such filing.

Item 9.01 Financial Statements and Exhibits.

(d) Exhibits

Exhibit

No. Description

99.1 Press release, dated August 5, 2026 of Montauk Renewables, Inc.

104 Cover Page Interactive Data File (embedded within the Inline XBRL document)

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

MONTAUK RENEWABLES, INC.

Date:

August 5, 2026

By:

/s/ Kevin A. Van Asdalan

Name:

Title:

Kevin A. Van Asdalan

Chief Financial Officer

EX-99.1

EX-99.1

Filename: mntk-ex99_1.htm · Sequence: 2

EX-99.1

Exhibit 99.1

Montauk Renewables Announces Second Quarter 2026 Results

PITTSBURGH, PENNSYLVANIA – August 5, 2026—Montauk Renewables, Inc. (“Montauk” or “the Company”) (NASDAQ: MNTK), a renewable energy company specializing in the management, recovery, and conversion of biogas into renewable natural gas (“RNG”), today announced financial results for the second quarter ended June 30, 2026.

Second Quarter Highlights:

• Revenues of $54.0 million, increased 19.7 % year-over-year

• Net income of $0.2 million, increased 104.1% year-over-year

• Non-GAAP Adjusted EBITDA of $12.3 million, increased 144.5% year-over-year

• RNG production of 1.5 million MMBtu, increased 3% year-over-year

• RINs from operations sold of 14.3 million, increased 29.1% year-over-year

In July 2026, we began generating power for sale from our Turkey, North Carolina facility. This production of power is expected to be eligible to generate both swine RECs and enhanced RECs in subsequent months. As we work to increase the volumes of power and RECs that are able to be generated from our volume of produced syngas, we have identified specific programming modifications to our installed electrical switchgear. The installation of these modifications will provide for both the increase in production volumes as well as enhance protection of our processing equipment and electrical transformers. We expect to have all programming completed by mid-August and consistently generate power and RECs from all available collected feedstock volumes.

We continue to progress with our installation of feedstock collection at our targeted 400 thousand to 450 thousand hog spaces. As of the end of July, we have entered into long term agreements with over fifty separate farming locations providing us access to at least 350 thousand hog spaces. We are currently able to collect from more than 250 thousand hog spaces and will continue farm site collection equipment installations during the second half of 2026.

Second Quarter Financial Results

Total revenues in the second quarter of 2026 were $54.0 million, an increase of $8.9 million (19.7%) compared to $45.1 million in the second quarter of 2025. The increase is primarily related to environmental attribute revenues from RINs sold related to the distribution of RINs from our GreenWave joint venture, which had no RINs distributed and sold in the second quarter of 2025. Our second quarter of 2026 RNG volumes sold under fixed/floor-price contracts decreased approximately 80.0% compared to the second quarter of 2025 due to the expiration of fixed price pathway contracts. Our RNG commodity revenue decreased approximately 63.7% which was offset by an increase in RINs sold of 29.1%. Our RINs generated and unseparated decreased approximately 95.4% as a result of the transition to the Biogas Regulatory Reform Rule in 2025.

Operating and maintenance expenses for our RNG facilities in the second quarter of 2026 were $15.6 million, a decrease of $1.4 million (8.2%) compared to $17.0 million in the second quarter of 2025. Our McCarty facility operating and maintenance expenses decreased approximately $0.9 million primarily due to the timing of maintenance of gas processing equipment. Our Apex facility operating and maintenance expenses decreased approximately $0.5 million primarily due to timing of gas processing preventative maintenance. Our Renewable Electricity Generation operating and maintenance expenses in the second quarter of 2026 were $5.1 million, an increase of $0.3 million (5.3%) compared to $4.8 million in the second quarter of 2025. The increase was primarily driven by an increase in non-capitalizable costs of $1.2 million for our Montauk Ag Renewables project. Our Bowerman facility operating and maintenance expenses decreased approximately $0.7 million, primarily driven by the decreased wellfield operational costs and timing of gas processing preventative maintenance. We recorded approximately $8.3 million of expenses in the second quarter of 2026 related to the cost of RINs distributed from GreenWave and the costs related to pathway dispensing associated with our dispensing RNG in exclusive unique and proprietary pathways. Total general and administrative expenses were $7.7 million in the second quarter of 2026, a decrease of $1.4 million (15.2%) compared to $9.1 million in the second quarter of 2025, driven by one-time accelerated vesting of $1.6 million from certain restricted share awards in 2025.

Operating loss in the second quarter of 2026 was $0.1 million compared to $2.4 million in the second quarter of 2025. We recognized income of $3.8 million from our GreenWave joint venture in the second quarter of 2026. Net

1

income in the second quarter of 2026 was $0.2 million compared to a net loss of $5.5 million in the second quarter of 2025.

Second Quarter Operational Results

We produced 1.5 million Metric Million British Thermal Units (“MMBtu”) of RNG during the second quarter of 2026, an increase of 43 thousand (3.0%) compared to 1.4 million MMBtu produced in the second quarter of 2025. Our McCarty facility produced 53 thousand MMBtu more in the second quarter of 2026 compared to the second quarter of 2025 as a result of landfill host wellfield operational and collection system enhancements. Our Apex facility produced 39 thousand MMBtu more in the second quarter of 2026 as compared to second quarter of 2025 as a result of increased feedstock gas from our improvements related to the landfill collection system. Our Galveston facility produced 26 thousand MMBtu fewer in the second quarter of 2026 compared to the second quarter of 2025 as a result of the landfill host assuming responsibility of wellfield operations and maintenance in 2026. Our Atascocita facility produced 37 thousand MMBtu fewer in the second quarter of 2026 compared to the second quarter of 2025 as a result of landfill host wellfield operational and collection system enhancement project timing and planned facility maintenance. We produced approximately 44 thousand megawatt hours (“MWh”) in Renewable Electricity in the second quarter of 2026, an increase of 2 thousand MWh compared to 42 thousand MWh produced in the second quarter of 2025. Our Bowerman facility produced approximately 3 thousand MWh more in the second quarter of 2026 compared to the second quarter of 2025. The increase is primarily related to increased gas flows due to landfill host wellfield improvements.

2026 Full Year Outlook

RNG revenues are expected to range between $175 and $190 million (unchanged)

RNG production volumes are expected to range between 5.8 and 6.0 million MMBtu (unchanged)

REG revenues are expected to range between $23 and $26 million

REG production volumes are expected to range between 185 and 195 thousand MWh

The reduction in REG revenues and volumes outlook relates to our current expectations on the commencement of revenue and REG generation at our Montauk Ag Renewables facility.

2

Conference Call Information

The Company will host a conference call August 6, 2026 at 8:30 a.m. Eastern time to discuss results. The registration for the conference call will be available via the following link:

• https://register-conf.media-server.com/register/BI0c92589308504408b2dab7f3408891bf

Please register for the conference call and webcast using the above link in advance of the call start time. The webcast platform will register your name and organization as well as provide dial-ins numbers and a unique access pin. The conference call will be broadcast live and be available for replay at https://edge.media-server.com/mmc/p/6xvvvg5h/ and on the Company’s website at https://ir.montaukrenewables.com after 11:30 a.m. Eastern time on the same day through August 6, 2027.

Use of Non-GAAP Financial Measures

This press release and the accompanying tables include references to EBITDA and Adjusted EBITDA, which are Non-GAAP financial measures. We present EBITDA and Adjusted EBITDA because we believe the measures assist investors in analyzing our performance across reporting periods on a consistent basis by excluding items that we do not believe are indicative of our core operating performance.

In addition, EBITDA and Adjusted EBITDA are financial measurements of performance that management and the board of directors use in their financial and operational decision-making and in the determination of certain compensation programs. EBITDA and Adjusted EBITDA are supplemental performance measures that are not required by or presented in accordance with GAAP. EBITDA and Adjusted EBITDA should not be considered alternatives to net income (loss) or any other performance measure derived in accordance with GAAP, or as an alternative to cash flows from operating activities or a measure of our liquidity or profitability.

About Montauk Renewables, Inc.

Montauk Renewables, Inc. (NASDAQ: MNTK) is a renewable energy company specializing in the management, recovery and conversion of biogas into 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, develops, operates and manages landfill methane-fueled renewable energy projects. The Company has current operations at 13 operating projects and on going development projects located in California, Idaho, Ohio, Oklahoma, Pennsylvania, North Carolina, South 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. For more information, visit https://ir.montaukrenewables.com

Company Contact:

John Ciroli

Chief Legal Officer (CLO) & Secretary

investor@montaukrenewables.com

(412) 747-8700

Investor Relations Contact:

Georg Venturatos

Gateway Investor Relations

MNTK@gateway-grp.com

(949) 574-3860

3

Safe Harbor Statement

This release contains “forward-looking statements” within the meaning of U.S. federal securities laws that involve substantial risks and uncertainties. All statements other than statements of historical or current fact included in this report are forward-looking statements. Forward-looking statements refer to our current expectations and projections relating to our financial condition, results of operations, plans, objectives, strategies, future performance, and business. Forward-looking statements may include words such as “anticipate,” “assume,” “believe,” “can have,” “contemplate,” “continue,” “strive,” “aim,” “could,” “design,” “due,” “estimate,” “expect,” “forecast,” “goal,” “intend,” “likely,” “may,” “might,” “objective,” “plan,” “predict,” “project,” “potential,” “seek,” “should,” “target,” “will,” “would,” and other words and terms of similar meaning in connection with any discussion of the timing or nature of future operational performance or other events. For example, all statements we make relating to our future results of operations, financial condition, expectations and plans, including those related to the Montauk Ag project in North Carolina, the GreenWave joint venture, the Bowerman RNG Facility, the development of a biogenic carbon dioxide facility and the related offtake, the Emvolon collaboration and pilot project, the Rumpke RNG Relocation project, the Tulsa facility project, the resolution of gas collection issues at the McCarty facility, the delays and cancellations of landfill host wellfield expansion projects, the mitigation of wellfield extraction environmental factors at the Rumpke and Apex facilities, how we may monetize RNG production and weather-related anomalies are forward-looking statements. All forward-looking statements are subject to risks and uncertainties that may cause actual results to differ materially from those that we expect and, therefore, you should not unduly rely on such statements. The risks and uncertainties that could cause those actual results to differ materially from those expressed or implied by these forward-looking statements include but are not limited to: our ability to develop and operate new renewable energy projects, including with livestock farms, and related challenges associated with new projects, such as achieving anticipated levels of energy output on a sustained basis on the announced timeline, identifying suitable locations, obtaining and refinancing or otherwise repaying acquisition financing and unexpected delays in construction and development; reduction or elimination of government loans, subsidies and other economic incentives to the renewable energy market, as a result of the current presidential administration and otherwise; the inability to complete strategic development opportunities; widespread manmade, natural and other disasters (including severe weather events), health emergencies, dislocations, geopolitical instabilities or events (including the current unrest in the Middle East), domestic protests and other forms of civil unrest, terrorist activities, international hostilities, government shutdowns, political elections, security breaches, cyberattacks or other extraordinary events that impact general economic conditions, energy markets, financial markets and/or our business and operating results; taxes, tariffs, duties or other assessments on equipment necessary to generate or deliver renewable energy or continued inflation that raise our operating costs and increase the construction costs of our existing or new projects; rising interest rates increase the borrowing costs of indebtedness; the failure to attract and retain qualified personnel or a possible increased reliance on third-party contractors as a result, and the potential unenforceability of non-compete clauses with our employees; the length of development and optimization cycles for new projects, including the design and construction processes for our livestock farm and other renewable energy projects; dependence on third parties for the manufacture of products and services and our landfill operations; the quantity, quality and consistency of our feedstock volumes from both landfill and livestock farm operations; reliance on interconnections with and access to electric utility distribution and transmission facilities and gas transportation pipelines for our Renewable Natural Gas and Renewable Electricity Generation segments; our ability to renew pathway provider sharing arrangements at historical counterparty share percentages; our projects not producing expected levels of output; potential benefits associated with the combustion-based oxygen removal condensate neutralization technology; concentration of revenues from a small number of customers and projects; our outstanding indebtedness, ability to refinance indebtedness at acceptable rates or at all and restrictions under existing and future indebtedness; our ability to extend our fuel supply agreements prior to expiration; our ability to meet milestone requirements under our power purchase agreements; existing regulations and changes to regulations and policies that effect our operations; expected impacts of the Production Tax Credit and other tax credit benefits under the Inflation Reduction Act of 2022; decline in public acceptance and support of renewable energy development and projects; our expectations regarding Environmental Attribute volume requirements and prices and commodity prices; our expectations regarding the period during which we qualify as an emerging growth company under the Jumpstart Our Business Startups Act (“JOBS Act”); our expectations regarding future capital expenditures, including for the maintenance of facilities; our expectations regarding the use of net operating losses before expiration; our expectations regarding more attractive carbon intensity scores by regulatory agencies for our livestock farm projects; market volatility and fluctuations in commodity prices and the market prices of Environmental Attributes and the impact of any related hedging activity; regulatory changes in federal, state and international environmental attribute programs and the need to obtain and maintain regulatory permits, approvals, and consents; profitability of our planned livestock farm projects; sustained demand for renewable energy; potential liabilities from contamination and environmental conditions; potential exposure to costs and liabilities due to extensive environmental, health and safety laws; impacts of climate change, extreme and changing weather patterns

4

and conditions and natural disasters; failure of our information technology and data security systems; increased competition in our markets; ability to keep up with technology innovations; concentrated stock ownership by a few stockholders and related control over the outcome of all matters subject to a stockholder vote; and other risks and uncertainties detailed in the section titled “Risk Factors” in our latest Annual Report on Form 10-K and our other filings with the SEC.

We make many of our forward-looking statements based on our operating budgets and forecasts, which are based upon detailed assumptions. While we believe that our assumptions are reasonable, we caution that it is very difficult to predict the impact of known factors, and it is impossible for us to anticipate all factors that could affect our actual results. All forward-looking statements attributable to us are expressly qualified in their entirety by these cautionary statements as well as others made in our Securities and Exchange Commission filings and public communications. You should evaluate all forward-looking statements made by us in the context of these risks and uncertainties. The forward-looking statements included herein are made only as of the date hereof. We undertake no obligation to publicly update or revise any forward-looking statement as a result of new information, future events, or otherwise, except as required by law.

5

MONTAUK RENEWABLES, INC.

CONSOLIDATED BALANCE SHEETS

(Unaudited)

(in thousands, except share data)

as of June 30,

as of December 31,

ASSETS

2026

2025

Current assets:

Cash and cash equivalents

$

15,757

$

23,752

Accounts and other receivables

5,554

9,167

Current restricted cash

8

8

Income tax receivable

1,308

702

Current portion of derivative instruments

220

Prepaid insurance and other current assets

4,677

3,306

Total current assets

$

27,304

$

37,155

Non-current restricted cash

$

2,725

$

430

Property, plant and equipment, net

385,624

341,395

Goodwill and intangible assets, net

19,070

19,605

Deferred tax assets

3,455

5,550

Operating lease right-of-use assets

7,358

9,082

Finance lease right-of-use assets

8

39

Equity method investment

3,715

3,824

Other assets

21,447

18,380

Total assets

$

470,706

$

435,460

LIABILITIES AND STOCKHOLDERS' EQUITY

Current liabilities:

Accounts payable

$

25,800

$

15,638

Accrued liabilities

15,998

11,735

Current portion of operating lease liability

2,531

3,287

Current portion of finance lease liability

1

32

Current portion of long-term debt

2,733

Total current liabilities

$

44,330

$

33,425

Long-term debt, less current portion

149,635

126,000

Non-current portion of operating lease liability

4,960

5,880

Non-current portion of finance lease liability

8

8

Asset retirement obligations

7,218

6,960

Other liabilities

25

39

Total liabilities

$

206,176

$

172,312

STOCKHOLDERS’ EQUITY

Common stock, $0.01 par value, authorized 690,000,000 shares; 143,912,811 shares issued at June 30, 2026 and December 31, 2025; 143,244,544 shares outstanding at June 30, 2026 and December 31, 2025

1,431

1,431

Treasury stock, at cost, 2,521,886 shares June 30, 2026 and December 31, 2025

(21,681

)

(21,681

)

Additional paid-in capital

227,453

226,302

Retained earnings

57,327

57,096

Total stockholders' equity

264,530

263,148

Total liabilities and stockholders' equity

$

470,706

$

435,460

6

MONTAUK RENEWABLES, INC.

CONSOLIDATED STATEMENTS OF OPERATIONS

(Unaudited)

(in thousands, except share and per share data)

Three Months Ended June 30,

Six Months Ended June 30,

2026

2025

2026

2025

Total operating revenues

$

54,020

$

45,127

$

100,447

$

87,730

Operating expenses:

Operating and maintenance expenses

29,061

21,864

52,215

39,422

General and administrative expenses

7,666

9,044

15,686

17,798

Royalties, transportation, gathering and production fuel

8,814

9,168

16,851

16,739

Depreciation, depletion and amortization

7,904

7,029

16,277

13,293

Impairment loss

650

377

1,093

2,424

Total operating expenses

$

54,095

$

47,482

$

102,122

$

89,676

Operating loss

$

(75

)

$

(2,355

)

$

(1,675

)

$

(1,946

)

Other expenses (income):

Interest expense

$

1,531

$

1,216

$

2,866

$

2,459

Income from equity investment

(3,772

)

(7,092

)

Loss on extinguishment of debt

944

Other (income) loss

(50

)

40

(316

)

(13

)

Total other (income) expenses

$

(2,291

)

$

1,256

$

(3,598

)

$

2,446

Income (loss) before income taxes

$

2,216

$

(3,611

)

$

1,923

$

(4,392

)

Income tax expense

1,990

1,876

1,692

1,559

Net income (loss)

$

226

$

(5,487

)

$

231

$

(5,951

)

Income (loss) per share:

Basic

$

0.00

$

(0.04

)

$

0.00

$

(0.04

)

Diluted

$

0.00

$

(0.04

)

$

0.00

$

(0.04

)

Weighted-average common shares outstanding:

Basic

143,244,544

143,035,626

143,244,544

142,874,606

Diluted

143,932,316

143,035,626

143,916,829

142,874,606

7

MONTAUK RENEWABLES, INC.

CONSOLIDATED STATEMENTS OF CASH FLOWS

(Unaudited)

(in thousands)

Six Months Ended June 30,

2026

2025

Cash flows from operating activities:

Net income (loss)

$

231

$

(5,951

)

Adjustments to reconcile net income to net cash provided by operating

activities:

Depreciation, depletion and amortization

16,277

13,293

Provision for deferred income taxes

2,095

1,596

Loss on extinguishment of debt

944

-

Stock-based compensation

1,151

3,639

Derivative mark-to-market adjustments and settlements

220

341

Net (gain) loss on sale or disposal of assets

(13

)

36

Decrease in earn-out liability

360

Accretion of asset retirement obligations

258

239

Amortization of debt issuance costs

482

195

Impairment loss

1,093

2,424

Non-cash expense - RINs from equity method investment

7,201

Income from equity method investment

(7,092

)

Cash provided (used) by changes in assets and labilities:

Accounts receivable

3,613

629

Royalty offset long term receivable

(2,921

)

(2,645

)

Critical spare inventory

(204

)

(1,030

)

Prepaid insurance and expenses

(1,371

)

(2,003

)

Income tax payables

(606

)

(606

)

Accounts payable and Accrued liabilities

8,935

7,247

Other

152

(418

)

Net cash provided by operating activities

$

30,445

$

17,346

Cash flows from investing activities:

Capital expenditures

$

(55,560

)

$

(45,298

)

Capital contributions to equity method investments

$

(2,150

)

Cash collateral deposits

$

2

Proceeds from sale of assets

33

Net cash used in investing activities

$

(55,527

)

$

(47,446

)

Cash flows from financing activities:

Repayments of long-term debt

(44,000

)

(6,000

)

Borrowings of long-term debt

155,000

20,000

Repayments of revolver

(105,000

)

Borrowings of revolver

20,000

Debt extinguishment costs

(944

)

Debt issuance costs

(5,644

)

Common stock issuance

4

Treasury stock purchase

(354

)

Finance lease payments

(30

)

(36

)

Net cash provided in financing activities

$

19,382

$

13,614

Net decrease in cash and cash equivalents and restricted cash

$

(5,700

)

$

(16,486

)

Cash and cash equivalents and restricted cash at beginning of period

$

24,190

$

46,004

Cash and cash equivalents and restricted cash at end of period

$

18,490

$

29,518

Reconciliation of cash, cash equivalents, and restricted cash at end of period:

Cash and cash equivalents

$

15,757

$

29,133

Restricted cash and cash equivalents - current

8

8

Restricted cash and cash equivalents - non-current

2,725

377

$

18,490

$

29,518

Supplemental cash flow information:

Cash paid for interest, net of $4,426 and $64 capitalized respectively

$

3,178

$

2,501

Cash paid for income taxes

202

569

Accrual for purchase of property, plant and equipment included in accounts payable and accrued liabilities

17,275

19,367

Non-cash RIN distribution from equity method investment

7,201

8

MONTAUK RENEWABLES, INC.

NON-GAAP FINANCIAL MEASURES

(Unaudited)

(in thousands):

The following table provides our EBITDA and Adjusted EBITDA, as well as a reconciliation to net income (loss) which is the most directly comparable GAAP measure for the three and six months ended June 30, 2026 and 2025, respectively:

Three Months Ended June 30,

2026

2025

Net income (loss)

$

226

$

(5,487

)

Depreciation, depletion and amortization

7,904

7,029

Interest expense

1,531

1,216

Income tax expense

1,990

1,876

Consolidated EBITDA

11,651

4,634

Impairment loss

650

377

Net loss on disposal of assets

21

Adjusted EBITDA

$

12,301

$

5,032

Six Months Ended June 30,

2026

2025

Net income (loss)

$

231

$

(5,951

)

Depreciation, depletion and amortization

16,277

13,293

Interest expense

2,866

2,459

Income tax expense

1,692

1,559

Consolidated EBITDA

21,066

11,360

Impairment loss

1,093

2,424

Loss on extinguishment of debt

944

Net (gain) loss on sale of assets

(13

)

36

Adjusted EBITDA

$

23,090

$

13,820

9

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Aug. 05, 2026

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Entity Registrant Name

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Entity Emerging Growth Company

true

Entity File Number

001-39919

Entity Incorporation, State or Country Code

DE

Entity Tax Identification Number

85-3189583

Entity Address, Address Line One

5313 Campbells Run Road

Entity Address, Address Line Two

Suite 200

Entity Address, City or Town

Pittsburgh

Entity Address, State or Province

PA

Entity Address, Postal Zip Code

15205

City Area Code

(412)

Local Phone Number

747-8700

Written Communications

false

Soliciting Material

false

Pre-commencement Tender Offer

false

Pre-commencement Issuer Tender Offer

false

Entity Ex Transition Period

false

Title of 12(b) Security

Common Stock, par value $0.01 per share

Trading Symbol

MNTK

Security Exchange Name

NASDAQ

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Area code of city

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Cover page.

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For the EDGAR submission types of Form 8-K: the date of the report, the date of the earliest event reported; for the EDGAR submission types of Form N-1A: the filing date; for all other submission types: the end of the reporting or transition period. The format of the date is YYYY-MM-DD.

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- Definition

The type of document being provided (such as 10-K, 10-Q, 485BPOS, etc). The document type is limited to the same value as the supporting SEC submission type, or the word 'Other'.

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- Definition

Address Line 1 such as Attn, Building Name, Street Name

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Address Line 2 such as Street or Suite number

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Name of the City or Town

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Code for the postal or zip code

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Name of the state or province.

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- Definition

A unique 10-digit SEC-issued value to identify entities that have filed disclosures with the SEC. It is commonly abbreviated as CIK.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Exchange Act

-Number 240

-Section 12

-Subsection b-2

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- Definition

Indicate if registrant meets the emerging growth company criteria.

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- Definition

Indicate if an emerging growth company has elected not to use the extended transition period for complying with any new or revised financial accounting standards.

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-Section B

-Subsection 2

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Commission file number. The field allows up to 17 characters. The prefix may contain 1-3 digits, the sequence number may contain 1-8 digits, the optional suffix may contain 1-4 characters, and the fields are separated with a hyphen.

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Two-character EDGAR code representing the state or country of incorporation.

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- Definition

The exact name of the entity filing the report as specified in its charter, which is required by forms filed with the SEC.

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-Publisher SEC

-Name Exchange Act

-Number 240

-Section 12

-Subsection b-2

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- Definition

The Tax Identification Number (TIN), also known as an Employer Identification Number (EIN), is a unique 9-digit value assigned by the IRS.

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Local phone number for entity.

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- Definition

Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act.

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Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act.

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Title of a 12(b) registered security.

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Name of the Exchange on which a security is registered.

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- Definition

Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as soliciting material pursuant to Rule 14a-12 under the Exchange Act.

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-Subsection 12

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Trading symbol of an instrument as listed on an exchange.

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Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as written communications pursuant to Rule 425 under the Securities Act.

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