A San Francisco Bay Area real estate firm under investigation by the U.S. Securities and Exchange Commission reported that it had insufficient equity to return the total principal for some of its investors, after finding that six of its 30 properties have no equity, according to an investor update Wednesday.

The SEC launched a fact-finding inquiry into Novato-based Professional Financial Investors Inc. after company founder Kenneth J. Casey died in May. Last month, the firm had all of its corporate officers resign and tapped Michael Hogan of Armanino as PFI’s chief restructuring officer. In a June 28 investor update, Hogan verified that the company had engaged in “serious misconduct” in the three decades years prior to Casey’s death.