A longtime regulator with CFTC and SEC experience is joining Davis Polk & Wardwell as a new partner in the firm's Washington office.  Susan Ervin is a federal derivatives regulator and will focus on the wave of new rules facing the derivatives industry. Ms. Ervin spent 15 years at the CFTC, including more than 10 years as chief counsel and deputy director of trading and markets.  In these roles, she "helped to design regulatory approaches to the developing markets for swaps and other [OTC] derivative products." She left in 1997 to join Dechert, where she led the firm’s derivatives practice. In 2009, Ms. Ervin then returned to government as an SEC senior adviser, where she is now.  She'll leave the Agency to join Davis Polk on 7/1/11.  While at the SEC, Ms. Ervin helped draft rules;  she also is the incoming chairwoman of the Derivatives and Futures Law Committee of the ABA.   [Dealook, 6/8/11]