Between 2010 and 2012 Gary Rabin, then CEO of the stem cell player Advanced Cell Technology, sold $1.5 million worth of his shares in 27 transactions. But according to the SEC, Rabin never told investors of his stock sales--a strict no-no that is now costing the ex-CEO a $175,000 penalty, with the Marlborough, MA-based biotech company agreeing to fork over $375,000 as it reviews its compliance policy. The company's stock plunged more than 20% on Thursday morning. "It's not merely a technical lapse when executives fail to report their transactions in company stock, because investors are consequently denied important and timely information about how an insider is potentially viewing the company's future prospects," said Michele Wein Layne, Director of the SEC's Los Angeles Regional Office. "Instead of reporting his numerous company stock sales within two days as typically required, Rabin waited more than two years and compromised Advanced Cell Technology's financial reporting obligations." Release