POWER SOLUTIONS INTERNATIONAL, INC.

CONDENSED CONSOLIDATED BALANCE SHEETS

CONDENSED CONSOLIDATED STATEMENTS OF INCOME

CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS’ EQUITY

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS

Note 1. Summary of Significant Accounting Policies and Other Information

Nature of Business Operations

Power Solutions International, Inc. (“Power Solutions,” “PSI” or the “Company”), a Delaware corporation, is a global producer and distributor of a broad range of high-performance, certified, low-emission power systems, including alternative-fueled power systems for original equipment manufacturers (“OEMs”) of off-highway industrial equipment and large custom-engineered integrated electrical power generation systems.

The Company’s customers include large, industry-leading and multinational organizations. The Company’s products and services are sold predominantly to customers throughout North America as well as to customers located throughout the Pacific Rim and Europe. The Company’s power systems are highly engineered, comprehensive systems which, through the Company’s technologically sophisticated development and manufacturing processes, including its in-house design, prototyping, testing and engineering capabilities and its analysis and determination of the specific components to be integrated into a given power system (driven in large part by emission standards and cost considerations), allow the Company to provide its customers with power systems customized to meet specific OEM application requirements, other customers’ technical specifications and requirements imposed by environmental regulatory bodies.

The Company’s power system configurations range from a basic engine integrated with appropriate fuel system components to completely packaged power systems that include any combination of cooling systems, electronic systems, air intake systems, fuel systems, housings, power takeoff systems, exhaust systems, hydraulic systems, enclosures, brackets, hoses, tubes and other assembled componentry. The Company also designs and manufactures large, custom-engineered integrated electrical power generation systems for both standby and prime power applications. The Company purchases engines from third-party suppliers and produces internally designed engines, all of which are then integrated into its power systems.

Of the other components that the Company integrates into its power systems, a substantial portion consist of internally designed components and components for which it coordinates significant design efforts with third-party suppliers, with the remainder consisting largely of parts that are sourced off-the-shelf from third-party suppliers. Some of the key components (including purchased engines) embody proprietary intellectual property of the Company’s suppliers. As a result of its design and manufacturing capabilities, the Company is able to provide its customers with a power system that can be incorporated into a customer’s specified application. In addition to the certified products described above, the Company sells diesel, gasoline and non-certified power systems and aftermarket components.

Stock Ownership and Control

Weichai America Corp., a wholly-owned subsidiary of Weichai Power Co., Ltd. (HK2338, SZ000338) (herein collectively referred to as “Weichai”), beneficially owns approximately 46.5% of the outstanding shares of the Company’s Common Stock as of August 26, 2025. Weichai has entered into an Investor Rights Agreement (the “Rights Agreement”) with the Company. The Rights Agreement provides Weichai with representation on the Company’s Board of Directors (the “Board”) and management representation rights. Weichai currently hasfour representatives on the Board, which constitutes the majority of the directors serving on the Board. In addition, the Company and Weichai have entered into a Shareholders Agreement with the Company’s founders (the “Founders”), pursuant to which the Founders have agreed to vote in favor of Weichai’s designees to the Board and for certain other matters. The Founders currently beneficially own approximately 6.3% of the Company’s Common Stock as of September 18, 2025. As a result, Weichai is able to exercise control over matters requiring stockholders’ approval, including the election of directors, amendment of the Company’s Certificate of Incorporation (the “Charter”) and approval of significant corporate transactions. This control could have the effect of delaying or preventing a change of control of the Company or changes in management and will make the approval of certain transactions impractical without the support of Weichai. According to the Rights Agreement, during any period when the Company is a “controlled company” within the meaning of the Nasdaq Listing Rules, it will take such measures as to avail itself of the “controlled company” exemptions available under Rule 5615 of the Nasdaq Listing Rules from Rules 5605(b), (d) and (e) to the extent applicable.

Liquidity

During the first nine months of 2025, the Company reported net income of $97.9 million and cash provided by operations of $28.7 million. On July 30, 2025, the Company amended its Uncommitted Revolving Credit Agreement (the “Revolving Credit Agreement”), which extended the maturity date from August 30, 2025 to July 30, 2027 (See Note 6. Debt) and increased the borrowing capacity to$135.0 million. As the Company has achieved profitability, is generating positive cash flows from operating activities, and has amended the Revolving Credit Agreement, the Company has concluded that its existing cash and cash equivalents and cash from operations will be sufficient for the Company for at least twelve months from the issuance of these condensed consolidated financial statements.

Basis of Presentation and Consolidation

The Company is filing this Form 10-Q for the quarterly period ended September 30, 2025, which contains unaudited condensed consolidated financial statements as of September 30, 2025 and for the three and nine months ended September 30, 2025 and 2024.

The condensed consolidated financial statements include the accounts of Power Solutions International, Inc. and its wholly-owned subsidiaries and majority-owned subsidiaries in which the Company exercises control. The condensed consolidated financial statements were prepared in accordance with generally accepted accounting principles in the United States (“U.S. GAAP”) and rules and regulations of the SEC for interim financial reporting. All intercompany balances and transactions have been eliminated in consolidation.

Certain information and note disclosures normally included in the Company’s annual financial statements prepared in accordance with U.S. GAAP have been condensed or omitted. The accompanying unaudited Condensed Consolidated Financial Statements have been prepared in accordance with the instructions to Form 10-Q and Article 8 of Regulation S-X and include all of the information and disclosures required by U.S GAAP for interim financial reporting. These unaudited Condensed Consolidated Financial Statements should be read in conjunction with the Consolidated Financial Statements of the Company and related footnotes for the year ended December 31, 2024, included in the 2024 Annual Report on Form 10-K, filed with the SEC on March 24, 2025 (the “2024 Annual Report”). The Company’s significant accounting policies are described in the aforementioned 2024 Annual Report. The accompanying interim financial information is unaudited; however, the Company believes the financial information reflects all adjustments (consisting of items of a normal recurring nature) necessary for a fair presentation of its financial position, results of operations and cash flows in conformity with U.S. GAAP. Operating results for interim periods are not necessarily indicative of annual operating results.

Segments

The Company operates asone business and geographic operating segment. Operating segments are defined as components of a business that can earn revenues and incur expenses for which discrete financial information is available that is evaluated on a regular basis by the chief operating decision maker (“CODM”). The Company’s CODM is its principal executive officer, who decides how to allocate resources and assess performance. A single management team reports to the CODM, who manages the entire business. The Company’s CODM reviews consolidated statements of income to make decisions, allocate resources and assess performance, and the CODM does not evaluate the profit or loss from any separate geography or product line.

Concentrations

The following table presents customers individually accounting for more than 10% of the Company’s net sales:

The following table presents customers individually accounting for more than 10% of the Company’s trade accounts receivable:

The following table presents suppliers individually accounting for more than 10% of the Company’s purchases:

**Less than 10% of the total

Use of Estimates

The preparation of consolidated financial statements in conformity with U.S. GAAP requires that management make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the consolidated financial statements and the reported amounts of revenue and expenses during the reporting period. Significant estimates and assumptions include the valuation of allowances for credit losses, inventory reserves, warranty reserves, stock-based compensation, evaluation of goodwill, other intangibles, property, plant and equipment for impairment, income tax valuation allowances and determination of useful lives of long-lived assets. Actual results could materially differ from those estimates.

Restricted Cash

Restricted cash consists of funds that are contractually restricted as to usage or withdrawal due to required minimum levels of cash collateral for letters of credits and contractual agreements with customers. As of September 30, 2025 and December 31, 2024, the Company had restricted cash of$3.7 million and$3.2 million, respectively, which includes $1.4 million restricted cash held in escrow which could be required to be refunded to the customer if conditions occur as defined in the agreement with the customer. The Company has not recognized revenue associated with the restricted cash. The deferred revenue is included within Noncurrent Contract Liabilities on the Consolidated Balance Sheets.

Inventories

The Company’s inventories consist primarily of engines and parts. Engines are valued at the lower of cost, including estimated freight-in, or net realizable value. Parts are valued at the lower of cost or net realizable value, except for integral parts provided by customers for installation on custom ordered engines. Such parts are accounted for as noncash consideration which is valued at fair value. Net realizable value approximates replacement cost. Cost is principally determined using the first-in, first-out method and includes material, labor and manufacturing overhead. It is the Company’s policy to review inventories on a continuing basis for obsolete, excess and slow-moving items and to record valuation adjustments for such items in order to eliminate non-recoverable costs from inventory. Valuation adjustments are recorded in an inventory reserve account and reduce the cost basis of the inventory in the period in which the reduced valuation is determined. Inventory reserves are established based on quantities on hand, usage and sales history, customer orders, projected demand and utilization within a current or future power system. Specific analysis of individual items or groups of items is performed based on these same criteria, as well as on changes in market conditions or any other identified conditions.

Inventories consist of the following:

Activity in the Company’s inventory allowance was as follows:

As of September 30, 2025, the Company’s inventory included$2.8 million of raw materials provided by its customers for installation in the fulfillment of its performance obligations to these customers and recorded an associated contract liability. See Note 2. Revenue for further information regarding contract assets and contract liabilities.

Other Accrued Liabilities

Other accrued liabilities consisted of the following:

1 As of September 30, 2025 and December 31, 2024 accrued litigation includes accruals related to various ongoing legal matters including associated legal fees. See Note 10. Commitments and Contingencies for further information regarding the various ongoing legal matters.

2 The Company has an incentive compensation plan, which authorizes the granting of a variety of different types of awards including, but not limited to, non-qualified stock options, incentive stock options, Stock Appreciation Rights (“SARs”), Restricted Stock Awards (“RSAs”), deferred stock and performance units to its executive officers, employees, consultants and Directors. The SAR awards granted for the year ended September 30, 2025 and December 31, 2024 were all liability classified awards and remained outstanding. See Note 13. Stock-Based Compensation in the Company’s 2024 Annual Report for additional information on the SARs and RSAs.

Warranty Costs

The Company offers a standard limited warranty on the workmanship of its products that in most cases covers defects for a defined period. Warranties for certified emission products are mandated by the U.S. Environmental Protection Agency (the “EPA”) and/or the California Air Resources Board (the “CARB”) and are longer than the Company’s standard warranty on certain emission-related products. The Company’s products also carry limited warranties from suppliers. The Company’s warranties generally apply to engines fully manufactured by the Company and to the modifications the Company makes to supplier base products. Costs related to supplier warranty claims are generally borne by the supplier and passed through to the end customer.

Warranty estimates are based on historical experience and represent the projected cost associated with the product. A liability and related expense are recognized at the time products are sold. The Company adjusts estimates when it is determined that actual costs may differ from initial or previous estimates. The Company’s warranty liability is generally affected by failure rates, repair costs and the timing of failures. Future events and circumstances related to these factors could materially change the estimates and require adjustments to the warranty liability. In addition, new product launches require a greater use of judgment in developing estimates until historical experience becomes available.

Accrued product warranty activities are presented below:

*Warranty costs, net of supplier recoveries and other adjustments, were $5.3 million and $5.8 million for the nine months ended September 30, 2025 and 2024, respectively. Supplier recoveries were $0.1 million and $0.7 million for the nine months ended September 30, 2025 and 2024, respectively.

**Changes in estimates for preexisting warranties reflect changes in the Company’s estimate of warranty costs for products sold in prior periods. Such adjustments typically occur when claims experience deviates from historical and expected trends. During thenine months ended September 30, 2025, the Company recorded a cost for changes in estimates of preexisting warranties of $0.7 million, or $0.03 per diluted share. During thenine months ended September 30, 2024, the Company recorded a cost of $2.1 million, or $0.09 per diluted share.

Recently Issued Accounting Pronouncements– Adopted

In November 2023, the FASB issued ASU 2023-07, Improvements to Reportable Segment Disclosures – Segment Reporting (Topic 280). The amendments to this standard require public entities to disclose more detailed information about their reportable segments’ significant expenses on an interim and annual basis. The amendments to this standard do not change how a public entity identifies its operating segments, aggregates those operating segments, or applies the quantitative thresholds to determine its reportable segments. The amendments to this standard apply to all public entities that are required to report segment information in accordance with Topic 280, Segment Reporting and are effective for fiscal years beginning after December 15, 2023, and interim periods within fiscal years beginning after December 15, 2024. The Company adopted this guidance for the year ending December 31, 2024 and subsequent interim periods. See Note 15. Segment Reporting for the new disclosures required by the standard.

Recently Issued Accounting Pronouncements – Not Yet Adopted

In December 2023, the FASB issued ASU 2023-09, Improvements to Income Tax Disclosures - Income Taxes (Topic 740). The amendments to this standard enhances the transparency and decision usefulness of income tax disclosures, primarily related to rate reconciliation and income taxes paid information as well as effectiveness of overall income tax disclosures. The new standard is effective for non-public companies, and public business entities that meet the definition of a smaller reporting company as defined by the SEC, for annual periods beginning after December 15, 2024. The Company is required to adopt the guidance for its 2025 annual report filed on Form 10-K, though early adoption is permitted. The Company is currently evaluating the impact of these amendments on its disclosures, but this standard update will not impact the Company's results of operations or financial position.

In November 2024, the FASB issued ASU 2024-03, Income Statement - Reporting Comprehensive Income: Expense Disaggregation Disclosures (Subtopic 220-40). This update requires entities to provide more detailed disclosures about the components of significant expense categories, enhancing the transparency and decision usefulness of financial statements. The amendments in this update are intended to provide investors with additional information about specific expense categories in the notes to the financial statements at interim and annual reporting periods. The updated standard is effective for annual periods beginning after December 15, 2026, and interim reporting periods thereafter, although early adoption is permitted.

While we anticipate that the adoption of this standard will require additional disclosures, the Company is currently assessing the impact of the amendment to this standard on its consolidated financial statements.

In July 2025, the FASB issued ASU 2025-05, Financial Instruments - Credit Losses: Measurement of Credit Losses for Accounts Receivable and Contract Assets (Topic 326). The update permits entities to elect a practical expedient for estimating expected credit losses on current trade receivables and current contract assets by assuming that conditions existing at the balance sheet date will remain unchanged over the life of those assets. The update standard is effective for fiscal years beginning after December 15, 2025, including interim periods within those fiscal years, with early adoption permitted. The Company is currently assessing the impact of the amendment to this standard on its consolidated financial statements.

Note 2. Revenue

Disaggregation of Revenue

The following table summarizes net sales by end market:

The following table summarizes net sales by geographic area:

Contract Balances

Most of the Company’s contracts are for a period of less than one year; however, extended warranty contracts extend beyond one year. The timing of revenue recognition may differ from the time of invoicing to customers and these timing differences result in contract assets, or contract liabilities on the Company’s Consolidated Balance Sheets. Contract assets include amounts related to the contractual right to consideration for completed performance when the right to consideration is conditional. The Company records contract liabilities when cash payments are received or due in advance of performance. The fair value of noncash consideration of parts provided by customers is recorded in contract liabilities. Contract assets and contract liabilities are recognized at the contract level.

During the nine months ended September 30, 2025 and 2024, the Company recognized $10.6 million and $1.4 million, respectively, of revenue upon satisfaction of performance obligations related to amounts that were included in the net contract liabilities balance as of December 31, 2024 and 2023, respectively. During thethree months ended September 30, 2025 and 2024, the Company recognized $1.7 million and $0.7 million, respectively, of revenue upon satisfaction of performance obligations related to amounts that were included in the net contract liabilities balance as of June 30, 2025 and 2024, respectively.

Remaining Performance Obligations

The Company has elected the practical expedient to not disclose remaining performance obligations that have expected original durations of one year or less. For performance obligations that extend beyond one year, the Company had$2.1 million of remaining performance obligations as of September 30, 2025, primarily related to extended warranties. The Company expects to recognize revenue related to these remaining performance obligations of approximately $0.2 million in the remainder of 2025, $0.2 million in 2026, $1.5 million in 2027, $0.2 million in 2028, andnone in 2029 and beyond.

Note 3. Weichai Transactions

Weichai Shareholder’s Loan Agreements

The Company entered into a $105.0 million Shareholder’s Loan Agreement (the “SLA”) with Weichai in August 2024. The SLA was fully repaid during the second quarter of 2025. See additional discussion of these debt agreements in Note 6. Debt.

Weichai Collaboration Arrangement and Related Party Transactions

The Company and Weichai executed a strategic collaboration agreement (the “Collaboration Agreement”) in March 2017 in order to achieve their respective strategic objectives and enhance the strategic cooperation alliance to share experiences, expertise and resources. Among other things, the Collaboration Agreement established a joint steering committee, permitted Weichai toselect a limited number of certain technical, marketing, sales, procurement and finance personnel to work at the Company and established several collaborations related to stationary natural-gas applications and Weichai diesel engines. The Collaboration Agreement provided for the steering committee to create various sub-committees with operating roles and otherwise governs the treatment of intellectual property of parties prior to the collaboration and the intellectual property developed during the collaboration. On March 22, 2023, the Collaboration Agreement was extended for an additional term ofthree years.

The Company evaluates whether an arrangement is a collaborative arrangement at its inception based on the facts and circumstances specific to the arrangement. The Company also reevaluates whether an arrangement qualifies or continues to qualify as a collaborative arrangement whenever there is a change in either the roles of the participants or the participants’ exposure to significant risks and rewards dependent on the ultimate commercial success of the endeavor. For those collaborative arrangements where it is determined that the Company is the principal participant, costs incurred and revenue generated from third parties are recorded on a gross basis in the financial statements. Purchases of inventory from Weichai were $3.1 million and $35.4 million for the three and nine months ended September 30, 2025, respectively. Purchases of inventory from Weichai were $13.2 million and $19.9 million for the three and nine months ended September 30, 2024, respectively.

In January 2022, PSIand Societe Internationale des Moteurs Baudouin (“Baudouin”), a subsidiary of Weichai, entered into an international distribution and sales agreement that enables Baudouin to bring PSI’s power systems line of products into the European, Middle Eastern, and African markets. In addition to sales, Baudouin will manage service, support, warranty claims, and technical requests. Refer to the Consolidated Balance Sheets and Statements of Income for detailed related party information.

See Note 14. Related Party Transactionsfor information regarding the purchase agreement with Shandong Weichai Import & Export Corporation, an affiliate of Weichai (“SWIEC”), and a manufacture of record (“MOR”) agreement with Weichai.

Note 4. Property, Plant and Equipment

Property, plant and equipment by type were as follows:

Note 5. Goodwill and Other Intangibles

Goodwill

The carrying amount of goodwill at both September 30, 2025 and December 31, 2024 was $29.8 million. Accumulated impairment losses at both September 30, 2025 and December 31, 2024 were $11.6 million.

Other Intangible Assets

Components of intangible assets are as follows:

Note 6. Debt

The Company’s outstanding debt consisted of the following:

Revolving Credit Agreement and Shareholder’s Loan Agreement

On August 30, 2024, the Company closed on the Revolving Credit Agreement, with Standard Chartered Bank (“Standard Chartered”) and two other lenders. The Revolving Credit Agreement allowed the Company to borrow up to$120.0 million and had a maturity date of August 30, 2025. The Revolving Credit Agreement was subject to customary events of default and covenants, including minimum consolidated EBITDA and Consolidated Interest Coverage Ratio covenants for the third and fourth quarters of 2024 and the first and second quarters of 2025. Borrowings under the Revolving Credit Agreement incurred interest at the applicable Secured Overnight Financing Rate (“SOFR”) plus 2.00% per annum. The obligations under the Revolving Credit Agreement were unconditionally guaranteed, on a joint and several basis, by certain wholly-owned, existing and subsequently acquired or formed direct and indirect subsidiaries of the Company, subject to customary exceptions. The obligations under the Revolving Credit Agreement were secured by substantially all assets of the Company and the Company’s wholly-owned subsidiaries. In addition, the Company paid fees of $0.6 million related to the Revolving Credit Agreement which were deferred and amortized over the term of the Revolving Credit Agreement. As part of the closing of the Revolving Credit Agreement, the Company made an initial draw in the amount of$100.0 million. The Company utilized the amount drawn under the Revolving Credit Agreement (i) to repay the outstanding balance of approximately $40.0 million under the Company’s Fourth Amended and Restated Uncommitted Revolving Credit Agreement, dated March 22, 2024, by and among the Company and Standard Chartered; and (ii) to prepay approximately $60.0 million under previous shareholder loan agreements between PSI and Weichai.

In connection with the Revolving Credit Agreement, on August 30, 2024, the Company also entered into a new SLA with Weichai, which allowed the Company to borrow up to$105.0 million and expired August 31, 2025. Borrowings under the SLAincurred interest at the applicable SOFR, plus 4.05% per annum. If the interest rate for any loan was lower than Weichai’s borrowing cost, the interest rate for such loan would be equal to Weichai’s borrowing cost plus 1.0%. The borrowing requests made under the SLA were subject to Weichai’s discretionary approval. The payment of the borrowings under the SLA was subordinated in all respects to the Revolving Credit Agreement with the exception that the Company was allowed to make a single payment of $10.0 million to Weichai. The $60.0 million portion of the initial advance under the Revolving Credit Agreement was applied to pay all principal, interest, and other amounts outstanding under the Shareholder’s Loan Agreements that the Company was previously party to with Weichai except for $25.0 million. In January 2025, the Company amended the Revolving Credit Agreement. After the amendment date, the Company was able to repay the outstanding balance under the

SLA in principal and interest provided there are no new borrowings under the SLA. In June 2025, the Company made payments totaling $10.2 million and fully repaid the outstanding balance under the SLA.

On July 30, 2025, the Company closed on the Second Amendment (the “Amendment”) to the Revolving Credit Agreement with Standard Chartered and three other lenders. The Amendment continues to enable the Company to borrow under a revolving line of credit secured by substantially all the Company’s tangible and intangible assets. The amended Revolving Credit Agreement extended the maturity to July 30, 2027, and increased the borrowing capacity of the revolving line of credit to a maximum of$135.0 million to the Company. The Amendment is subject to customary events of default and quarterly covenants, including minimum consolidated EBITDA, consolidated interest coverage ratio, and consolidated leverage ratio covenants for each fiscal quarter ending hereafter. Borrowings under the Amendment will incur interest at the applicable Secured Overnight Financing Rate (“SOFR”) plus 2.10%. In the event the Company’s majority shareholder, Weichai, holds less than fifty percent (50%) of the common equity of the Company, the interest rate under the Amended Credit Agreement will increase to the applicable SOFR plus 2.60% per annum. The obligations under the Amendment remain unconditionally guaranteed, on a joint and several basis, by certain wholly-owned, existing and subsequently acquired or formed direct and indirect subsidiaries of the Company, subject to customary exceptions. The obligations under the Amendment continue to be secured by substantially all assets of the Company and the Company’s wholly-owned subsidiaries. In addition, the Company paid fees of $1.2 million related to the Amendment which are deferred and amortized over the term of the Amendment. As of September 30, 2025, the Company had $95.0 million outstanding under the amended Revolving Credit Agreement.

As of September 30, 2025, the Company’s total outstanding debt obligations under the Revolving Credit Agreementand for finance leases and other debt were $96.7 million in the aggregate. The Company's total accrued interest for the Revolving Credit Agreement was $0.3 million and $1.2 million as of September 30, 2025 and December 31, 2024, respectively. Accrued interest is included within Other Accrued Liabilities on the Consolidated Balance Sheets.

Note 7. Other Non-current Liabilities

On June 14, 2024, the Company executed a non-interest bearing note payable of $4.5 million upon settlement of a legal matter. The note payable is due May 2028 and is discounted based on an imputed interest rate of 6.66%. The note payable includes an option for the Company to extend maturity of the note to September 2029 upon written notice before the thirty-seventh payment and, if such option is exercised, the maximum payment amount of the note increases to $4.8 million.

As of both September 30, 2025 and December 31, 2024 the current portion of the note of $0.7 million is included in other accrued liabilities in the Company’s Consolidated Balance Sheets.

The following table presents remaining maturities for the note payable as of September 30, 2025:

The Company recorded $0.3 million and $0.1 million discount amortization as interest expense as of September 30, 2025 and 2024, respectively.

Note 8. Leases

Leases

The Company has obligations under lease arrangements primarily for facilities, equipment and vehicles. These leases have original lease periods expiring between September 2025 and March 2036. The following table summarizes the lease expense by category in the Consolidated Statements of Income:

The following table summarizes the components of lease expense:

The following table presents supplemental cash flow information related to leases:

As of September 30, 2025 and December 31, 2024, the weighted-average remaining lease term was 8.2 years and 5.3 years for operating leases, respectively, and 4.3 years and 1.2 years for finance leases, respectively. As of September 30, 2025 and December 31, 2024, the weighted-average discount rate was 7.1% and 7.5% for operating leases, respectively, and 7.0% and 6.5%, respectively, for finance leases.

The following table presents supplemental balance sheet information related to leases:

1. Included in Property, plant and equipment, net for finance leases on the Consolidated Balance Sheets.

The following table presents maturity analysis of lease liabilities as of September 30, 2025:

Note 9. Fair Value of Financial Instruments

For assets and liabilities measured at fair value on a recurring and nonrecurring basis, a three-level hierarchy of measurements based upon observable and unobservable inputs is used to arrive at fair value. Observable inputs are developed based on market data obtained from independent sources, while unobservable inputs reflect the Company’s assumptions about valuation based on the best information available in the circumstances. Depending on the inputs, the Company classifies each fair-value measurement as follows:

•Level 1 – based on quoted prices in active markets for identical assets or liabilities;

•Level 2 – based on other significant observable inputs for the assets or liabilities through corroborations with market data at the measurement date; and

•Level 3 – based on significant unobservable inputs that reflect management’s best estimate of what market participants would use to price the assets or liabilities at the measurement date.

Financial Instruments Measured at Carrying Value

Current Assets

Cash and cash equivalents (Level 1) are measured at carrying value, which approximates fair value because of the short-term maturities of these instruments.

Debt

The Company measured its material debt obligations and notes payable at original carrying value. The fair value of the Revolving Credit Agreement and other short-term financing approximated carrying value, as it consisted primarily of variable rate loans. The Company measured its non-interest bearing note payable using a rate which the Company could obtain financing of similar nature from other sources at the date of the transaction. The unamortized discount is reported in the Consolidated Balance Sheets as a deduction from the face amount of the note payable. The Company measured its material debt obligations and note payable using Level 2 inputs as follows:

Other Financial Assets and Liabilities

In addition to the methods and assumptions used for the financial instruments discussed above, accounts receivable, net income tax receivable, accounts payable, and certain accrued expenses are measured at carrying value, which approximates fair value because of the short-term maturities of these instruments.

Note 10. Commitments and Contingencies

Legal Contingencies

The legal matters discussed below and others could result in losses, including damages, fines, civil penalties and criminal charges, which could be substantial. The Company records accruals for these contingencies to the extent the Company concludes that a loss is both probable and reasonably estimable. Regarding the matters disclosed below, unless otherwise disclosed, the Company has determined that liabilities associated with these legal matters are reasonably possible; however, unless otherwise stated, the possible loss or range of possible loss cannot be reasonably estimated. Given the nature of the litigation and investigations and the complexities involved, the Company is unable to reasonably estimate a possible loss for all such matters until the Company knows, among other factors the following:

•what claims, if any, will survive dispositive motion practice;

•the extent of the claims, particularly when damages are not specified or are indeterminate;

•how the discovery process will affect the litigation;

•the settlement posture of the other parties to the litigation; and

•any other factors that may have a material effect on the litigation or investigation.

However, the Company could incur judgments, enter into settlements or revise its expectations regarding the outcome of certain matters, and such developments could have a material adverse effect on the Company’s results of operations in the period in which the amounts are accrued and/or liquidity in the period in which the amounts are paid.

Jerome Treadwell v. the Company

In October 2018, a putative class-action complaint was filed against the Company and NOVAtime Technology, Inc. (“NOVAtime” or “Plaintiff”) in the Circuit Court of Cook County, Illinois. In December 2018, NOVAtime removed the case to the U.S. District Court for the Northern District of Illinois, Eastern Division (the “Court”) under the Class Action Fairness Act. Plaintiff has since voluntarily dismissed NOVAtime from the lawsuit without prejudice and filed an amended complaint in April 2019. The operative, amended complaint asserts violations of the Illinois Biometric Information Privacy Act (“BIPA”) in connection with employees’ use of the time clock to clock in and clock out using a finger scan and seeks statutory damages, attorneys’ fees, and injunctive and equitable relief. An aggrieved party under BIPA may recover (i) $1,000 per violation if the Company is found to have negligently violated BIPA or (ii) $5,000 per violation if the Company is found to have intentionally or recklessly violated BIPA plus reasonable attorneys’ fees. In May 2019, the Company filed its motion to dismiss the

Plaintiff’s amended complaint. In December 2019, the court denied the Company’s motion to dismiss. In January 2020, the Company moved for reconsideration of the Court’s order denying the motion to dismiss, or in the alternative, to stay the case pending the Illinois Appellate Court’s ruling in McDonald v. Symphony Healthcare on a legal question that would be potentially dispositive in this matter. In February 2020, the Court denied the Company’s motion for reconsideration, but required the parties to submit additional briefing on the Company’s motion to stay. In April 2020, the Court granted the Company’s motion to stay and stayed the case pending the Illinois Appellate Court’s ruling in McDonald v. Symphony Healthcare. In October 2020, after the McDonald ruling, the Court granted the parties’ joint request to continue the stay of the case for 60 days. The Court also ordered the parties to schedule a settlement conference with the Magistrate Judge in May 2021 which went forward without a settlement being reached. On May 22, 2023, the Company filed the answer to the amended complaint. Plaintiff and PSI have since reached a preliminary settlement of the case, and Plaintiff filed an Unopposed Motion for Preliminary Approval of Class Action Settlement on February 23, 2024. On February 5, 2025 Plaintiff filed an Unopposed Motion for Final Approval of the Class Settlement, which the Court granted on February 7, 2025. As of December 31, 2024, the Company had recorded an estimated liability of $2.4 million, recorded within Other accrued liabilitieson the Consolidated Balance Sheets related to the potential settlement of this matter. During the first quarter of 2025, the final settlement amount of $2.4 million was paid to the Plaintiff, of which $0.7 million was paid by the Company and $1.7 million was paid by the Company’s insurance carrier.

Mast Powertrain v. the Company

In February 2020, the Company received a demand for arbitration from Mast Powertrain, LLC (“Mast”) pursuant to a development agreement entered into in November 2011 (the “Development Agreement”). Mast claimed that it was owed more than$9.0 million in past royalties and other damages for products sold by the Company pursuant to the Development Agreement. The Company disputed Mast’s damages, denied that any royalties are owed to Mast, denied any liability, and counterclaimed for overpayment on invoices paid to Mast. Mast subsequently clarified its claim for past royalties owed to be approximately$4.5 million. In July 2021, the Company reached a settlement with Mast to resolve past claims for royalties owed for $1.5 million which the Company had previously recorded within Selling, general and administrative expenses in the Consolidated Statement of Income for the year-ended December 31, 2020. The Company fully paid the settlement as of December 31, 2022. In September 2023, Mast filed a lawsuit against the Company in the Eastern District of Texas Federal Court (“Court”), alleging, among other things, damages of approximately $6.0 million for fraudulent inducement leading to the 2021 arbitration settlement agreement and breach of said settlement agreement. Upon court order, the Company participated in separate mediations in May 2024 and December 2024, and no settlement was reached. The Company has filed a motion to stay the lawsuit and compel it to arbitration, and the Court granted that motion on January 31, 2025. As of both September 30, 2025 and December 31, 2024, the Company had recorded an estimated liability of $0.9 million, recorded within Other accrued liabilities on the Consolidated Balance Sheets related to the potential settlement of this matter.

Gary Winemaster v. The Company

In August 2021, the Company’s former Chairman of the Board and former Chief Executive Officer and President, Gary Winemaster (“Winemaster”), filed suit in the Court of Chancery of the State of Delaware against the Company and Travelers Casualty and Surety Company of America (“Travelers”) alleging the Company’s breach of its advancement obligations under Winemaster’s indemnification agreement and Travelers’ breach of the side A policy between Traveler’s and the Company of which Winemaster is a beneficiary. In his complaint, Winemaster was seeking reimbursement under his indemnification agreement in excess of $7.2 million of attorney’s fees plus interest incurred by Winemaster in his defense of the Department of Justice (“DOJ”) case, U.S. v. Winemaster et al. Since the filing of the complaint, the Company estimates that Travelers has paid approximately $8.8 million to Winemaster’s attorneys, Latham and Watkins, under the Company’s side A policy to settle existing outstanding attorney’s fees. Travelers is seeking reimbursement from the Company for those advances pursuant to the terms of the side A policy. In October 2021, the Company and Winemaster entered into a Stipulation and Advancement Order to handle all future attorney’s fees relating to his DOJ and SEC cases, to the extent not reimbursed by Travelers under the side A policy. In June 2024, the Company reached a settlement with Travelers for $4.5 million. As of both September 30, 2025 and December 31, 2024, the Company recorded the aforementioned settlement liability within Other noncurrent liabilities with the current portion within Other accrued liabilitieson the Consolidated Balance Sheets. Refer to Note 7. Other Non-current Liabilitiesfor additional information related to this settlement.

Indemnification Agreements

The Company holds a directors’ and officers’ liability insurance policy, which is renewed annually and currently expires in July 2026. The insurance policy includes standard exclusions including for any previously pending litigation.

Other Commitments and Contingencies

At September 30, 2025, the Company hadfour outstanding letters of credit totaling $1.8 million. The letters of credit primarily serve as collateral for certain facility leases and insurance policies. As discussed in Note 1. Summary of Significant Accounting Policies and Other Information, the Company had restricted cash of $3.7 million as of September 30, 2025, related to these letters of credit and cash held in escrow due to a customer agreement.

Note 11. Income Taxes

On a quarterly basis, the Company computes an estimated annual effective tax rate considering ordinary income and related income tax (benefit) expense. Ordinary income refers to income before income tax (benefit) expense excluding significant, unusual or infrequently occurring items. The tax effect of an unusual or infrequently occurring item is recorded in the interim period in which it occurs.

Through March 31, 2025, the Company maintained a full valuation allowance against its deferred tax assets due to significant negative evidence, about realizability of the assets, including cumulative losses and substantial doubt about its ability to continue as a going concern. Due to the successful refinancing of its debt in July 2025, the Company concluded that substantial doubt about its ability to continue as a going concern no longer exists. After evaluating all available evidence, including the alleviation of substantial doubt about the Company’s ability to continue as a going concern, recent and forecasted earnings, historical performance, and the Company’s improved financial condition, management determined that it is more likely than not that its deferred tax assets will be realized. As a result, the Company released an additional $29.2 million of the valuation allowance in the second quarter of 2025 and recognized an additional $7.0 million tax benefit in the third quarter of 2025. As of September 30, 2025 and December 31, 2024, the Company had net deferred tax assets (liabilities) of $19.5 million and $(1.6) million, respectively.

The effective tax rate for the three and nine months ended September 30, 2025 was (3.3)% and (21.3)%, respectively, compared to an effective tax rate for the three and nine months ended September 30, 2024 of 1.6% and 2.9%. The negative effective tax rates in 2025 reflect the impact of the valuation allowance reversal. The Company did not pay any income taxes during the three months ended September 30, 2025, and paid approximately $8.1 million in income taxes during the nine months ended September 30, 2025.

Recent Tax Legislation

The One, Big, Beautiful Bill Act (the “Act”) was signed into law on July 4, 2025. The Act contains significant tax law changes with various effective dates affecting business taxpayers. Among the tax law changes that will impact the Company relate to the timing of certain tax deductions including depreciation expense, research and development (“R&D”) expenditures and interest expense. The Company implemented the provisions of the Act in the third quarter of 2025. As a result, the Company recognized incremental tax timing benefits primarily related to the restoration of 100% bonus depreciation and the ability to immediately expense R&D costs under Section 174. These changes affected the mix between current and deferred taxes but did not have a material impact on the Company’s overall income tax expense for the quarter.

Note 12. Stockholders’ Equity

Common and Treasury Stock

The changes in shares of Common and Treasury Stock are as follows:

Note 13. Earnings Per Share

The Company computes basic earnings per share by dividing net income by the weighted-average common shares outstanding during the year. Diluted earnings per share is calculated to give effect to all potentially dilutive common shares that were outstanding during the year. Weighted-average diluted common shares outstanding primarily reflect the additional shares that would be issued upon the assumed exercise of stock options and the assumed vesting of unvested share awards. The treasury stock method has been used to compute diluted earnings per share for the three and nine months ended September 30, 2025 and 2024.

The Company issued SARs and RSAs, all of which have been evaluated for their potentially dilutive effect under the treasury stock method. See Note 13. Stock-Based Compensation in the Company’s 2024 Annual Report for additional information on the SARs and the RSAs.

The computations of basic and diluted earnings per share are as follows:

The aggregate number of shares excluded from the diluted earnings per share calculations, because they would have been anti-dilutive, were none for both the three months ended September 30, 2025 and 2024 andnone and 0.1 million for thenine months ended September 30, 2025 and 2024, respectively. For the three and nine months ended September 30, 2025 and 2024, SARs and RSAs were not included in the diluted earnings per share calculations as they would have been anti-dilutive because the Company’s average stock price was less than or equal to the exercise price of the SARs or the grant price of the RSAs.

Note 14. Related Party Transactions

Weichai Transactions

See Note 3. Weichai Transactions for information regarding the Weichai Shareholder’s Loan Agreement and Collaboration Agreement.

Other Related Party Transactions

See Note 10. Commitments and Contingencies for information regarding the Company’s indemnification obligations related to certain former directors and officers of the Company.

In January 2025, the Company entered into afive-year purchase agreement with SWIEC, for the exclusive purchase and distribution of certain engine and engine components for the fulfillment of a contract with a customer in North America. The supply agreement includes annual minimum requirements of products ordered during the initial term. If all minimum targets are met within the first three-year periods, the contract may be negotiated to extend beyond thefive-year initial term. The annual minimum requirements are as follows:

In February 2025, the Company entered into a MOR agreement with Weichai. The MOR agreement requires the Company to pay Weichai a fee of 1.75% of gross revenues generated by the sale of certain engines manufactured by Weichai. Fees are due on a quarterly basis. The MOR agreement further requires the 1.75% fee to be paid for applicable sales of these engines beginning January 2024. As of September 30, 2025, the Company had recorded an estimated liability of $0.1 million, recorded within Other accrued liabilitieson the Consolidated Balance Sheets for the fee due to Weichai. The MOR agreement expires in December 2029.

Note 15. Segment Reporting

Operating segments are defined as components of a business that can earn revenues and incur expenses for which discrete financial information is available that is reviewed on a regular basis by the chief operating decision maker (“CODM”). The Company operatesasone business and geographic operating and reportable segment.

Chief Operating Decision Maker

The Company’s CODM is its Chief Executive Officer (“CEO”). The CEO oversees the strategic planning and direction of the Company, and the CEO has final approval in assessing the Company’s performance and allocating its resources.

Identification of Reportable Segment

The Company’s single reportable segment derives revenues primarily in North America from customers by designing, engineering, manufacturing, marketing and selling a broad range of advanced, emission-certified engines and power systems that are powered by a wide variety of clean, alternative fuels, including natural gas, propane, and biofuels, as well as gasoline and diesel options, within the power systems, industrial and transportation end markets. Revenue is attributed to geographic areas based on the country of sale. The sources of external revenue by end market and geographic area are previously disclosed in Note 2. Revenue.

The Company evaluated the basis for the CODM's decisions about the allocation of Company resources as well as the basis for the CODM's assessments of the evaluation of the Company's (segment) performance. Specifically, the Company evaluated the financial information that is generally provided and / or is available to the CODM. The Company’s CODM reviews consolidated statements of income to make decisions, allocate resources and assess performance.

Measurement

The CODM assesses performance and decides how to allocate resources primarily using consolidated revenue by end market and consolidated net income (loss). The CODM uses consolidated net income (loss) to monitor budget and forecast information to actual results. The CODM reviews cash, accounts receivable, inventory, accounts payable, and total debt; however other long-lived asset information is not reviewed by the CODM.

The accounting policies of the Company’s single reportable segment are the same as those described in the Note 1. Summary of Significant Accounting Policies and Other Information. The measure of segment assets is consolidated total assets presented in the Company’s Consolidated Balance Sheets. Note 1 Concentrations discloses customers individually accounting for more than 10% of the Company’s consolidated net sales.

Significant Expenses

Significant segment expenses are presented in the Consolidated Statements of Income.