O'Melveny & Myers' sole resident Singapore partner Nathan Bush has left the firm to join DLA Piper.

Bush is joining DLA Piper's Singapore office as Asia head of investigations and Asia head of antitrust.

A disputes specialist, Bush focuses on investigations and regulatory compliance issues with an emphasis on competition law. He joined O'Melveny in 2001 and made partner in 2009. He was based in the firm's Beijing office between 2004 and 2012, when he started to split his time between the Chinese capital and Singapore.

In late 2015, Bush became the only O'Melveny partner primarily based in the Singapore office after capital markets partner Andrew Hutton decided to relocate to Hong Kong to be closer to clients. Before that, in early 2014, Bush changed his primary residence from Beijing to Singapore, where the firm would lose more than a dozen senior lawyers in the following two years.

The departures included three former Singapore partners: disputes partner Dean Collins left to open a Singapore office for Dechert in early 2014, and restructuring partners Bertie Mehigan and Joel Hogarth left for Ashurst later that year. Both have since moved on from the British firm.

In 2014, The Asian Lawyer reported that ex-O'Melveny partners cited management's lack of understanding of Asian clients' unique needs for flexible fee arrangements, and the firm's emphasis on disputes work as reasons for leaving. O'Melveny chairman Brad Butwin denied both claims and maintained that the firm focused more on connecting its Asia practice with the US practice than growing headcounts in individual offices. In October, our most recent Asia 100 survey found that in 2015, O'Melveny's Asia lawyer headcount of 53 was less than half the 114 lawyers it reported five years ago.

The exits spread into Hong Kong this year when the former office head – international arbitration partner Friven Yeoh – left for Sidley Austin with two counsel.

DLA Piper is also home to several ex-O'Melveny lawyers. Most recently, the firm hired Hong Kong-based restructuring partner Andrew Payne, who will reunite with two of his O'Melveny colleagues Mark Fairbairn and Ashley Bell. Both Fairbairn and Bell joined DLA in early 2014.

In June 2016, former O'Melveny Shanghai managing partner Li Qiang also quit the firm for DLA Piper alongside former counsel Stewart Wang, who became a partner at his new firm.

In Singapore, O'Melveny is now is left with two associates – Ning Qiao, who moved to the city-state from Beijing with Bush, and Wincen Santoso, an Indonesia-qualified disputes lawyer who had worked closely with Bush. According to its website, Hong Kong partner Hutton and Menlo Park partner David Makarechian both spend time in Singapore.

Elsewhere in Asia, Han Kun Law Offices has recruited White & Case China head Li Xiaoming as a partner in its Beijing headquarters. Li had led White & Case's China practice since 2005 when he joined the US firm from legacy King & Wood, where he had been a partner since 1999.