Penson GHCO Announces PFIX API For Advanced Trading CHICAGO — Penson GHCO, the futures and derivatives clearing subsidiary of Penson Worldwide, Inc. (NASDAQ: PNSN), announced today the launch of PFIX API, an advanced electronic trading capability based on the securities industry FIX standard protocol. PFIX API supports sophisticated customers trading in multiple asset classes via their own trading software who are seeking an execution venue around the clock for futures trading... (click here to read more)