Law firm Wolf Popper, LLP announced Monday it has filed a class action lawsuit against investment bank Goldman Sachs on behalf of investors who purchased securities, options or common stock between August 2009 and April 2010. The suit claims Goldman Sachs did not disclose to shareholders that it was under investigation by the Securities Exchange Commission.

The SEC began investigating Goldman in 2008 for its role in the sale of a package of mortgage-related securities that were allegedly constructed and sold with the knowledge it would perform poorly. More recently, the SEC filed formal charges of fraud against the bank and one of its officials.

When the news of the SEC’s suit went public in mid-April, Goldman stock fell 13% in one day. Two weeks later, Goldman’s stock fell more than 9% in a single day.

According to Wolf Popper, Goldman never disclosed to its shareholders the SEC investigation, and knowingly misled investors to think Goldman was committed to its clients’ best interests.

The Wolf Popper press release did not specify a court date or contain any additional information on the suit.