Chinese firm Fangda Partners' longtime leader Jonathan Zhou is leaving the firm to join Alibaba-affiliated Ant Financial Services Group as general counsel.

Zhou will oversee the legal and compliance functions for Ant Financial, which operates Alipay, one of the most popular online payment services in China. He will report to Leiming Chen, the company's senior vice president in charge of legal, compliance and anti-money laundering matters.

Zhou, who currently chairs Fangda's management committee, will leave the firm once the committee's term ends and after helping with the transition of a new management team. In 1994, Zhou co-founded Fangda with a group of young lawyers in Shanghai and has since led the firm's growth from a local boutique firm to one of the most premium mainland Chinese law firms, competing directly in many aspects with global legal giants.