Stock Leaps in Debut

A Laguna Niguel company focusing on Internet-based infomercials began trading as a bulletin board stock Thursday, and, despite not making any regulatory filings, the price of its shares more than doubled.

eCommercial.com offers technology to send downloadable multimedia content, a field already crowded by the likes of RealNetworks Inc., Microsoft Corp., IBM Corp. and AT&T; Corp.

The company’s shares opened at $4.50 and rose as high as $9.50 before closing at $9.25, with 368,500 shares trading hands.