Company Description
ClearSign Technologies Corporation (NASDAQ: CLIR) is a Delaware corporation that designs and develops technologies aimed at decarbonization and improving the performance of industrial and commercial combustion and fuel safety systems. According to its SEC registration statements and company disclosures, ClearSign focuses on enhancing emissions performance, operational efficiency, energy efficiency, safety, hydrogen fuel use and overall cost-effectiveness in combustion applications across multiple industrial markets.
The company’s primary technologies are branded as ClearSign Core™ and ClearSign Eye™, along with other sensing configurations. These patented technologies are embedded in established original equipment manufacturer (OEM) products and are designed to enhance the performance of combustion systems and fuel safety systems. ClearSign states in its SEC filings that its ClearSign Core™ technology can improve combustion systems in a broad range of markets, including energy (upstream oil production, midstream gas processing and transportation, and downstream refining), institutional, commercial and industrial boilers, and the chemical and petrochemical industries.
Business focus and technology
In its S‑1 registration statement, ClearSign describes its business as designing and developing technologies for industrial and commercial combustion systems to improve emission and operational performance, energy efficiency and cost-effectiveness. The company explains that its ClearSign Core™ technology uses a specialized flame holder device to significantly reduce flame length and achieve low emissions without relying on external flue gas recirculation, selective catalytic reduction or high excess air systems. This positions the technology for applications where low-NOx and other emission control objectives are important to operators and regulators.
ClearSign’s public disclosures and press releases also describe advanced sensing technologies that support combustion and fuel safety, marketed under the ClearSign Eye™ brand and other sensing configurations. These technologies are intended to help operators monitor and manage flames and combustion conditions in industrial systems, contributing to safety and performance improvements.
Industry and markets served
ClearSign is classified under the industry category “Instruments and Related Products Manufacturing for Measuring, Displaying, and Controlling Industrial Process Variables” within the broader manufacturing sector. Company materials and SEC filings state that its technologies target a range of industrial markets where combustion and process heating are critical, including:
- Energy – upstream oil production, midstream gas processing and transportation, and downstream refining
- Commercial and industrial boilers
- Chemical and petrochemical industries
- Transport and power industries
Press releases further indicate that ClearSign’s technologies are used or evaluated in applications such as process heaters, hot oil heaters, retrofit projects at refineries and gas processing facilities, and low-emission flare retrofits for energy producers. Orders described in recent news items include engineering and burner projects for refineries in California, gas processing facilities in New Mexico and West Texas, and enclosed flare retrofits in California’s San Joaquin Valley.
Products and solutions
According to the company’s public descriptions and Polygon’s profile, ClearSign offers combustion and sensing technologies and related products that are applied through OEM partners and retrofit projects. These include:
- ClearSign Core™ process burners, including the “M” Series such as the ClearSign Core™ M25, used in process heaters and hot oil heaters
- Boiler and process burners based on ClearSign Core™ technology
- Low-emission flare burners and flare retrofit solutions, including enclosed flare retrofits with upgraded structure components and control systems
- ClearSign Eye™ and other sensing configurations for combustion and fuel safety systems
News releases also note that ClearSign conducts testing, engineering, flares and service work for customers, including comprehensive burner testing over a range of operating conditions and fuel blends, and computational fluid dynamics (CFD) analysis and engineering orders as the first phase of multi-burner retrofit projects.
Role in decarbonization and hydrogen-capable combustion
Across multiple press releases, ClearSign describes itself as a company whose technologies help industrial operators reduce emissions, increase efficiency and safety, and support the use of cleaner fuels including hydrogen. The company highlights an expanded portfolio of low-NOx burners, including Department of Energy-tested, 100% hydrogen-capable flexible fuel process burners. ClearSign has also reported orders for comprehensive testing of hydrogen-capable burners from petrochemical clients seeking performance mapping for potential deployment at processing facilities.
By focusing on low-emission combustion and hydrogen-capable burners, ClearSign positions its technologies for operators facing stricter environmental standards and exploring lower-carbon fuel options. Company communications emphasize that these technologies are intended to support decarbonization efforts while maintaining or improving operational performance and safety.
Corporate structure and listing
ClearSign Technologies Corporation is incorporated in Delaware, as disclosed in its S‑1 and S‑1/A registration statements. The company’s principal executive offices are located in Tulsa, Oklahoma. ClearSign’s common stock is listed on the Nasdaq Capital Market under the ticker symbol “CLIR”, as stated in SEC filings and registration statements.
In an 8‑K dated September 30, 2025, the company reported that Nasdaq granted an extension to regain compliance with the $1.00 minimum bid price requirement under Nasdaq Listing Rule 5550(a)(2). The filing notes that ClearSign’s common stock continues to trade on the Nasdaq Capital Market under the symbol “CLIR” while the company evaluates options to regain compliance, including the potential use of a reverse stock split if needed.
Capital markets activity and warrants
ClearSign’s S‑1 and S‑1/A filings describe a registration of shares of common stock underlying redeemable warrants that were issued in connection with a prior underwritten public offering. These filings explain that the company is registering shares issuable upon the exercise of warrants that have a specified exercise price and term, and that any proceeds from warrant exercises are intended for working capital, research and development, marketing and sales, and general corporate purposes. The registration statements also confirm that ClearSign is a smaller reporting company and a non-accelerated filer under SEC rules.
Governance and regulatory disclosures
Recent 8‑K filings detail governance and compliance matters, including:
- Changes in board and committee composition, such as appointments to the Audit and Risk Committee, Human Capital and Compensation Committee, and Nominating and Corporate Governance Committee
- Board determinations regarding independent director status under Nasdaq rules and Rule 10A‑3 under the Exchange Act
- Adoption of Amended and Restated Bylaws that, among other things, establish voting standards for director elections and modify procedures for stockholder proposals and nominations
- Modifications to forms of equity award agreements under the company’s 2021 Equity Incentive Plan, including changes to governing law and jurisdiction to align with Delaware incorporation
- Notices from Nasdaq regarding board independence and audit committee composition requirements and subsequent actions taken by the company to regain compliance
These filings provide investors with information about ClearSign’s corporate governance framework, listing compliance, and equity compensation arrangements.
Financial reporting and operating updates
ClearSign regularly reports its financial results through quarterly and annual filings and related 8‑K press release disclosures. For example, 8‑K filings dated August 15, 2025 and November 21, 2025 reference press releases and conference call transcripts discussing results for quarters ended June 30, 2025 and September 30, 2025. The company also issues press releases with preliminary, unaudited financial information, such as the January 7, 2026 announcement of expected record fourth quarter and full-year revenues for 2025.
Operational updates in company news highlight order flow, engineering projects, burner and flare orders, and testing engagements with energy producers, refiners, and petrochemical customers. These updates illustrate how ClearSign’s technologies are being applied in field installations, retrofit projects, and evaluation programs across its target markets.
Position within the manufacturing and industrial technology landscape
Within the manufacturing sector, ClearSign operates at the intersection of industrial combustion equipment, process control, and environmental performance. Its classification as an instruments and related products manufacturer for measuring, displaying, and controlling industrial process variables reflects the company’s focus on technologies that influence combustion behavior, emissions, and safety in industrial systems.
By embedding its patented technologies into OEM products and working directly with industrial operators on retrofit and engineering projects, ClearSign seeks to address regulatory and operational demands related to emissions, efficiency, and fuel flexibility. The company’s public disclosures emphasize applications in energy production and processing, boilers, chemical and petrochemical facilities, transport-related combustion systems, and power industry installations.