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Companies

ClearSign Technologies

Ultra-low NOx burner technology for refineries and boilers

Raised to date

$1.8M

of $1.8M offered across 1 Form D filing

Investors
1
Last filed
Jul 31, 2026

About

ClearSign Technologies Corporation is a Tulsa, Oklahoma-based public company (Nasdaq: CLIR) that develops industrial combustion and flame-sensing technologies. Its patented ceramic-based ClearSign Core technology is embedded in process burners, boiler burners, and flares to cut NOx emissions to ultra-low levels, as low as under 2.5 ppm in boiler applications, while improving energy efficiency. The company commercializes through partnerships with established burner and heater OEMs, and its ClearSign Eye product provides non-contact electrical flame sensing for industrial fuel-safety systems. Customers span refining, petrochemical, chemical, oil and gas production, and commercial/industrial boiler markets.

Patented ceramic-core combustion architecture achieves ultra-low NOx (sub-5 ppm) without the efficiency penalties of conventional low-emission burners, delivered through OEM partnerships with established heater manufacturers rather than direct sales.

Funding

  • EquityFiled Jul 31, 2026Form D
    $1.8M/ $1.8M

Product

ClearSign Core

Industrial combustion hardware

A patented ceramic-based combustion technology embedded in OEM equipment as process burners, boiler burners, flares, and midstream/power burners, including the M1 series burner ordered by heater manufacturer Tulsa Heaters Midstream.

  • Ultra-low NOx emissions, below 2.5 ppm in boiler applications
  • Ceramic-core burner architecture
  • Available as process burners, boiler burners, and flares

Built for

Refining, petrochemical, chemical, oil and gas production, and commercial/industrial boiler operators, reached via burner and heater OEMs

People on file