What changed in this filing

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Item 1. Business

2026-03-02 compared with 2025-03-24 · 48 added, 44 removed, 227 unchanged (29% of the section changed)

3 unchanged sentences

The Company’s products are primarily used by global original equipment manufacturers (“OEMs”) and end-user customers across a wide range of applications and equipment that includes standby and prime power generation, demand response, microgrid, combined heat and power, arbor equipment, material handling (including forklifts), agricultural and turf, construction, pumps and irrigation, compressors and utility vehicles.

As of January 1, 2024, the Company no longer sells emissions-certified engines into the on-road market.

The Company provides highly engineered, comprehensive solutions designed to meet specific customer application requirements and technical specifications, including those imposed by environmental regulatory bodies, including the U.S.

Environmental Protection Agency (“EPA”), the California Air Resources Board (“CARB”) and regulatory bodies within the European Union (“EU”).

Environmental Protection Agency (“EPA”), the California Air Resources Board (“CARB”), the People’s Republic of China’s Ministry of Ecology and Environment (“MEE”) and regulatory bodies within the European Union (“EU”).

The Company’s products include both sourced and internally designed and manufactured engines that are engineered and integrated with associated components.

72 unchanged sentences

• the worldwide growth of intermittent sources of energy, such as wind and solar, and an aged electric grid in the United States, coupled with power outage activity due to weather or power shutdowns, are driving increased demand for generators, microgrids and demand response equipment;

• increasingly stringent regulations and growing efforts to reduce emissions are driving demand for clean energy and alternatives to diesel power engines in several markets such as the power generation market for microgrids, oil and gas applications, and arbor care markets, among others;

• stringent regulations and growing efforts to reduce emissions are driving demand for clean energy and alternatives to diesel power engines in several markets such as the power generation market for microgrids, oil and gas applications, and arbor care markets, among others;

• growth in data centers and their increasing demand for electricity, which is driving growth for backup power (commercial generators/microgrids);

8 unchanged sentences

Leverage the Company’s relationship with Weichai

In March 2017, the Company executed a share purchase agreement (the “SPA”) with Weichai America Corp.

Under the terms of the SPA, Weichai invested $60.0 million in the Company (the “Weichai Transactions”) by purchasing a combination of newly issued Common Stock and preferred stock, par value $0.001 (the “Preferred Stock”), as well as a stock purchase warrant, which significantly strengthened the Company’s financial condition and contributed to the extinguishment of its $60.0 million term loan in 2017.

Weichai has also provided support for PSI’s business and operations through various shareholder loan agreements as described in Part II, Item 7.

Liquidity and Capital Resources .

The Company and Weichai also entered into a strategic collaboration agreement (the “Collaboration Agreement”) under which they have been working together to accelerate market opportunities for each company’s respective product lines across various geographic and end-user markets.

On March 22, 2023, the Collaboration Agreement was extended for an additional term of three years.

In March 2017, the Company and Weichai executed a strategic collaboration agreement (the “Collaboration Agreement”) under which they have been working together to accelerate market opportunities for each company’s respective product lines across various geographic and end-user markets.

On March 22, 2023, the Collaboration Agreement was extended for an additional term of three years, expiring in March 2026.

The Company received a renewal notice from Weichai and is in the process of negotiating the renewal of the Collaboration Agreement;

however, no formal extension has been executed as of the date of this filing.

The Collaboration Agreement provides the Company with strategic benefits and opportunities, including the ability to leverage Weichai’s strengths and capabilities in R&D, manufacturing, procurement and distribution and its widespread sales channels in China and other emerging markets.

2 unchanged sentences

Expand global business

Through the expansion of its product lineup and the entry into new markets, the Company has a history of growing its product offerings internationally beyond North America.

Through the expansion of its product lineup and the entry into new markets, the Compa ny has a history of growing its product offerings internationally beyond North America.

The Company sees long-term opportunity in continuing to grow its business worldwide with further R&D investment including new-product development and offerings.

14 unchanged sentences

The largest customer changes from time to time as a result of various factors, including prevailing market conditions, customers’ strategies and inventory of the Company’s power systems.

Each of the Company’s end markets have a variety of competitors, including engine manufacturers, independent suppliers and distributors of engines, fuel systems and component providers, manufacturers of power generation equipment, engine packagers and integrators, and the in-house operations of certain OEMs, some of which have longer operating histories, strong brand recognition and significantly greater financial and marketing resources.

and integrators, and the in-house operations of certain OEMs, some of which have longer operating histories, strong brand recognition and significantly greater financial and marketing resources.

Notwithstanding significant competition, the Company believes that the following factors provide it with a differentiated value proposition that allows the Company to compete effectively:

32 unchanged sentences

From time to time, the Company enters into agreements with its customers to fund a portion of the research, development and engineering costs of a particular project.

These reimbursements are accounted for as a reduction of the related research,

development and engineering expenditure.

These reimbursements are accounted for as a reduction of the related research, development and engineering expenditure.

The Company’s net research, development and engineering expenditures for 2025 and 2024 were $18.2 million and $20.1 million, respectively.

12 unchanged sentences

The Company entered into this supply agreement to source certain engines previously supplied by Shenyang Aerospace Mitsubishi Motors Engine Manufacturing Co., Ltd.

(“SAME”), whose ability to supply product was suspended because of the intensified enforcement and expansion of the UFLPA near the end of 2023.

(“SAME”), whose ability t o supply product was suspended because of the intensified enforcement and expansion of the UFLPA near the end of 2023.

Beginning December 2024, the supply agreement automatically extends for additional one-year terms unless a notice of termination is provided by either party six months prior to scheduled expiration.

14 unchanged sentences

It approves, through its human resources department, the replacement of key positions that it believes are critical to sustaining improved business performance and analyzes departure data to continually improve upon the experience of employees.

Turnover for salaried employees in 2024 was approximately 9.5%.The Company’s talent management and succession planning process includes the identification of key

positions based on current and future business strategies, the identification of potential successors, and a plan for talent development.

Turnover for salaried employees in 2025 was approximately 18.0% .The Company’s talent management and succession planning process includes the identification of key positions based on current and future business strategies, the identification of potential successors, and a plan for talent development.

The Company focuses on attracting and retaining the best employees by providing market competitive pay and benefits.

4 unchanged sentences

Employees participate in training sessions focused on these topics and are encouraged to promote behaviors that protect others from risk of injury.

The Company sets annual targets for its Total Recordable Incident Rate (“TRIR”) and Days Away, Restricted or Transferred (“DART”) and regularly reviews these metri cs.

For 2024, the Company achieved an overall TRIR of 4.418, meaning that for every 100 employees, 0.40 employees incurred an injury that resulted in recordable medical treatment.

The DART was 3.96 in 2024, meaning that for every 100 employees, 0.039 individuals experienced an incident that resulted in days away from work or restricted work tasks.

The Company sets annual targets for its Total Recordable Incident Rate (“TRIR”) and Days Away, Restri cted or Transferred (“DART”) and regularly reviews these metrics.

For 2025, the Company achieved an overall TRIR of 7.42, meaning that for every 100 full-time employees, 7.42 employees incurred an injury that resulted in recordable medical treatment.

The DART Rate was 4.22 in 2025, meaning that for every 100 full-time employees, 4.22 individuals experienced an incident that resulted in lost time or modified duty.

Environmental Matters

29 unchanged sentences

Once a power system is certified, regulatory agencies impose ongoing compliance requirements, which include testing newly produced power systems on a regular quarterly schedule to ensure ongoing compliance with applicable regulations.

In addition, there are field audit requirements, which require the removal of power systems from service at specified stages of their useful lives to perform confirmatory exhaust emissions testing and/or on-board diagnostic (“OBD”) system audits and testing.

In addition, there are field audit requirements, which require the removal of power

systems from service at specified stages of their useful lives to perform confirmatory exhaust emissions testing and/or on-board diagnostic (“OBD”) system audits and testing.

All of the Company’s emission-certified power systems meet existing exhaust emission standards of the EPA and CARB.

1 unchanged sentence

Information about the Company’s Executive Officers

The following selected information for each of the Company’s current executive officers was prepared as of March 17 2025 .

The following selected information for each of the Company’s current executive officers was prepared as of February 26, 2026 .

Executive Officer Since

2 unchanged sentences

Xun (Kenneth) Li 56 2022 Chief Financial Officer

Lehner 53 2024 General Counsel

Zhaoying (Dorothy) Du 48 2025 General Counsel and Corporate Secretary

(Dino) Xykis was appointed as the Chief Executive Officer on April 24, 2023, after serving as Interim CEO since June 2, 2022.

8 unchanged sentences

in Structural/Applied Mechanics from the University of Minnesota, Minneapolis.

Xun (Kenneth) Li was appointed as the Chief Financial Officer on August 26, 2022.

Li is an accomplished executive who has more than 20 years of professional experience in the areas of finance, accounting, financial planning & analysis, internal controls and strategy, among others.

Most recently, Mr.

Li served as Chief Financial Officer for ND Paper, a leading pulp, packaging and paper company, from 2020 to August 2022, where he was a member of the executive leadership management team with primary responsibility for finance, accounting, tax, auditing, treasury, risk management, internal audit, and strategic planning, among other areas, and served as a strategic advisor to the Chief Executive Officer.

Prior to this role, Mr.

Li was with Caterpillar Inc., a publicly traded company on the NYSE, from 2008 through 2020, where he served in various financial leadership positions, the most recent of which was chief financial officer of the global mining machine product group from 2013 to 2020.

Prior to Caterpillar, Mr.

Li was with Ford Motor Company, a publicly traded company on the NYSE, where he held finance leadership roles of increasing responsibility, from 2003 to 2008.

Li earned the Masters in Business Administration degree with high distinction and a Master of Science (M.S.) degree in Accounting, both from the University of Michigan.

He also holds an M.S.

in Mechanical Engineering from the University of Oklahoma and a Bachelors of Science degree in Mechanical Engineering from Shanghai JiaoTong University.

Li is also a certified public accountant in the state of Illinois.

Lehner was appointed as the General Counsel on March 4, 2024.

Lehner is an accomplished legal advisor who has more than 25 years of legal experience in the areas of corporate and board governance, dispute resolution, regulatory compliance, internal controls and strategy, among others.

Most recently, from May 2020 to February 2024, Mr.

Lehner served as associate general counsel and deputy general counsel for Guaranteed Rate, LLC, a leading mortgage company, where he was a member of the legal leadership team with primary responsibility for litigation and risk management.

Prior to this role, from 2015 through 2020, Mr.

Lehner was a partner with Kelley Drye & Warren LLP, where his practice focused on commercial litigation, regulatory and internal investigations and government enforcement actions.

Prior to Kelley Drye & Warren LLP, from 1997 to 2014, Mr.

Lehner worked at several other prestigious law firms.

Lehner holds a Juris Doctor degree from Duke University with high honors.

He also holds a Bachelor of Arts degree in political science from the University of Michigan with high honors.

Xun (Kenneth) Li was appointed Chief Financial Officer of Power Solutions International, Inc.

on August 26, 2022.

As Chief Financial Officer, Mr.

Li has responsibility for the Company’s finance, accounting, financial planning and analysis, treasury, tax, risk management, internal audit, and related functions, and supports the Chief Executive Officer and Board of Directors on financial and strategic matters.

From 2020 to August 2022, Mr.

Li served as Chief Financial Officer of ND Paper, a pulp, packaging, and paper company.

He was a member of the executive leadership team with responsibility for finance and accounting functions and strategic planning.

From 2008 to 2020, Mr.

Li held financial leadership positions at Caterpillar Inc., a publicly traded company, including serving as Chief Financial Officer of machine product group from 2013 to 2020.

From 2003 to 2008, Mr.

Li held finance leadership roles at Ford Motor Company, a publicly traded company.

Li holds a Master of Business Administration with high distinction and a Master of Science in Accounting from the University of Michigan, a Master of Science in Mechanical Engineering from the University of Oklahoma, and a Bachelor of Science in Mechanical Engineering from Shanghai Jiao Tong University.

He is a Certified Public Accountant in the state of Illinois.

Zhaoying (Dorothy) Du was appointed General Counsel and Corporate Secretary of Power Solutions International, Inc.

on September 15, 2025.

As General Counsel and Corporate Secretary, Ms.

Du has responsibility for the Company's legal affairs, corporate governance, compliance, risk management, securities, and related functions, and supports the Chief Executive Officer and Board of Directors on legal and strategic matters.

Du has 20 years of experience providing strategic legal counsel to U.S.

and multinational companies, leading initiatives to address complex commercial and regulatory matters, helping businesses manage risks, drive innovation, and implement pragmatic legal solutions that support business success.

From March 2025 to September 2025, Ms.

Du led the global supply chain legal team of Lenovo, a publicly traded company.

She was a member of the Lenovo global supply chain executive leadership team, advising on procurement, factory setup, trade compliance, regulatory risks, and contract negotiations across global operations.

From February 2016 to March 2025, Ms.

Du served as Global Head of Legal of Motorola Mobility, a Lenovo company, where she was a member of the executive leadership team, overseeing matters including artificial intelligence, R&D, commercial contracts, intellectual property, compliance, data privacy and information security, corporate governance, corporate secretary, litigation, and other legal functions.

From 2013 to 2016, she served as General Counsel of the China operations and Senior Counsel for compliance and risk management at The Warranty Group (now part of Assurant, Inc.).

From 2005 to 2012, Ms.

Du served as Co-Chair of the APAC Practice Group at Freeborn & Peters (now part of Smith, Gambrell & Russell, LLP) and as an attorney at Sonnenschein Nath & Rosenthal, LLP (now Dentons LLP), advising on cross-border transactions, securities, corporate governance, mergers and acquisitions, financing, compliance, and other complex matters.

Du holds a Juris Doctor degree from the University of Missouri - Kansas City School of Law, a Master of Arts degree in Political Science from the University of Georgia, and a Bachelor of Law degree from Sun Yat-Sen University Law School.

She is licensed to practice law in Illinois and is admitted to practice law in China.

Compared sentence by sentence after normalising whitespace, quotation marks, case and digits, so re-formatting and restated figures do not read as changed language. Wording changes appear as one removal and one addition. The current filing and the prior one are authoritative.

What changed 10-K

Item 1. Business