Singapore’s Allen & Gledhill has recruited six new partners for its arbitration practice, including five from local rival Rajah & Tann.

The group from Rajah & Tann specializes in energy, infrastructure and construction disputes and is headed by Chong Yee Leong, the firm’s former international arbitration practice head. He and fellow partners Chong Boon Leong, Kamilah Kasim, Allen Choong and Chua Kee Loon will join Allen & Gledhill May 1.

Allen & Gledhill, which has 300 lawyers, and Rajah & Tann, which has 370, are Singapore’s two largest law firms and major competitors. In a statement, Rajah & Tann said the firm was sad to see the partners leave but said the departures were due to "professional disagreements."

"The five partners left because they had different views of how certain initiatives within the firm should be pursued and handled," the firm said. Senior disputes partner Andre Yeap SC will take over as head of the firm’s arbitration practice, which still counts 11 partners. The firm says it has 130 disputes lawyers who also handle arbitrations.

Allen & Gledhill did not respond to requests for comment by press time.

In addition to the Rajah & Tann partners, former Singapore International Arbitration Center chief executive officer Minn Naing Oo is joining Allen & Gledhill June 1. Lucien Wong, Allen & Gledhill’s chairman and senior partner, told Singapore’s Business Times Thursday that Minn, who was born in Myanmar, will help spearhead a practice focusing on that newly opened market.

This is not the first big move for the five Rajah & Tann partners. They were all part of a 20-lawyer group that left the firm in 2003 to join the Singapore office of Jones Day. Four years later, 12 of the defectors returned to Rajah & Tann, including the five now leaving for Allen & Gledhill.

Chong Yee Leong first joined Rajah & Tann in 1995 from WongPartnership, where he had also been a partner. In Jones Day’s Singapore office, he had been head of the projects and infrastructure group as well as the international litigation and arbitration practice.

Chong Boon Leong also first joined Rajah & Tann in 1995 and became an equity partner in 2007. Choong and Chua were both promoted to equity partner at Rajah & Tann in 2011. Kasim, who is only qualified in Malaysia, was made a foreign law partner in 2011. She and Chong Yee Leong are also the principal partners in Kamilah & Chong, Rajah & Tann’s associated Kuala Lumpur firm. Chong Boon Leong and Choong are also concurrent partners in Kamilah & Chong.

Minn practiced at Rajah & Tann as an associate before joining the Singapore Ministry of Trade & Industry in 2002. He left the ministry, where he headed trade negotiations, to join SIAC in 2008.