A Bay Area real estate firm that’s under investigation by the U.S. Securities and Exchange Commission has asked for, and received, the resignation of all its corporate officers and hired a restructuring specialist.

Investors in Novato-based Professional Financial Investors Inc. received notice of the SEC investigation earlier this month in letters from Ragghianti Freitas partner Eric Sternberger, a lawyer hired to handle the transfer of ownership of the company and an associated fund, Professional Investors Security Fund Inc., after founder Kenneth J. Casey died in May. The letters indicated that the SEC last month opened “a fact-finding inquiry” into Casey and “his companies’ three decades of real estate investments.”