Herbert Smith's Asia managing partner is resigning to become chief executive officer of the Hong Kong Securities and Futures Commission (SFC), reports The Asian Lawyer.

Ashley Alder is set to leave Herbert Smith – where he has been Asia head since 2005 – on 30 September, when he will take up the top job at the Hong Kong regulator.

He will succeed Martin Wheatley, who left the SFC in June to head up the UK's new Financial Conduct Authority. Under Wheatley, the SFC took on a more active enforcement stance, aggressively prosecuting insider trading and investigating alleged corporate misconduct.

This will not be the first stint at the SFC for Alder, who joined Herbert Smith in 1984, moved to Hong Kong with the firm in 1989, and made partner in 1994. From 2001 to 2004, he left Herbert Smith to serve as executive director of the SFC's corporate finance division.

Herbert Smith senior partner Jonathan Scott said: "We are delighted for Ashley and honoured that one of our partners has been chosen to head up Hong Kong's chief financial regulatory body. This is a highly prestigious appointment and one which reflects enormous credit on him and the esteem in which he is held at the highest levels in the Hong Kong government."

A capital markets and M&A lawyer, Alder has worked on many of Herbert Smith's biggest deals in the region. He represented Chinese oil producer China National Offshore Oil Corp in its controversial and ultimately unsuccessful $18.5bn (£11.4bn) bid for US oil company Unocal in 2005m while he also led a team advising casino joint venture company MGM China Holdings on its $1.5bn (£920m) Hong Kong initial public offering this May.

"I think the market will welcome Ashley's appointment," said Davis Polk & Wardwell partner Bonnie Chan, previously a senior vice president of Hong Kong Exchanges and Clearing. "He has a well-rounded view, being a market practitioner for many years and also having the benefit of previously working as a regulator," she added.

Unlike most law firm partners shifting to government roles, Alder may not have to take too sharp a pay cut. According to the SFC's 2010 annual report, its chief executive officer earned $1.2m (£736,000) last year, compared to 2010-11 profits per equity partner at Herbert Smith of £892,000. The firm's global revenue for the same period was £465m with an 18% contribution from its Asian offices.