Linklaters' US structured finance and derivatives chief Gary Barnett has left the firm to take a newly-created role at the US Commodity Futures Trading Commission (CFTC).

Barnett – who has spent seven years at the magic circle firm since joining in 2004 from Shearman & Sterling – has been appointed to head up the Division of Swap Dealer and Intermediary Oversight, a new subdivision of the CFTC charged with policing complex securities.

The agency recently created the division with new powers granted under the Dodd-Frank financial regulatory legislation, which was enacted last year. The appointment comes at a pivotal time for the agency, as it plans to bulk up its securities division.

At Linklaters, Barnett was involved in the development and implementation of clearing systems for the derivatives markets and has advised clients on the implementation of Dodd-Frank and other regulatory reforms affecting the derivatives and securitisation markets.

He is also a former partner at US law firms Cadwalader Wickersham and Taft and O'Melveny & Myers.

The magic circle firm has yet to appoint a replacement for Barnett. A spokesperson commented: "We thank Gary for his contribution to the firm and we wish all the best in his future career."

The news comes as former acting US solicitor general Neal Katyal joins Hogan Lovells in Washington DC.

Katyal served as acting solicitor general from May 2010, when Elena Kagan left to become a US Supreme Court justice, until June, when Donald Verrilli was sworn in as Kagan's permanent successor.

High-profile roles Katyal has taken include serving as lead counsel for Guantanamo Bay detainees in Hamdan v Rumsfeld, which resulted in the 2006 Supreme Court ruling that the Bush administration's military tribunals had violated prisoners' human rights.

Katyal's other credentials include serving as a national security adviser in the Justice Department under President Bill Clinton and as Al Gore's co-counsel in the case over the disputed Florida election results in 2000 that went to the Supreme Court.