ClearSign Combustion in Seattle, Washington, is one of the first small “early-stage” companies to raise public capital under the JOBS Act enacted in early April. The company’s core expertise is in using computer technology to make boilers, furnaces, turbines, and other combustion systems more efficient. It sold three million shares at $4 each, raising $12 million in the process. After expenses and underwriters’ fees, the company expects to net about $9.5 million. But without the JOBS Act it might not even have bothered.