A Kirkland & Ellis London corporate partner is leaving the firm to join a private equity investment firm.

According to two people familiar with the move, partner Joel Arnell is leaving the U.S. firm’s London office to join investment firm Triton Partners, one of Kirkland’s key clients.

Arnell specializes in advising private equity sponsors on M&A and portfolio work and joined Kirkland as a partner in 2016 from Linklaters, where he was a managing associate.

A Kirkland receptionist confirmed he had left the firm. Arnell did not respond to requests for comment.

He recently advised Triton on its acquisition of European online tour operator Sunweb Group.

Arnell’s move follows a flurry of departures from Kirkland’s London office in recent months, including Kirkland tax partner Mark Ingram who joined alternative asset manager Intermediate Capital Group (ICG) this month, and private equity partners Gavin Gordon and David Arnold, who joined U.S. rival Willkie Farr & Gallagher in May.

Recent corporate hires for Kirkland in the City include private equity heavyweight Adrian Maguire from Freshfields Bruckhaus Deringer in January, a year after fellow Freshfields private equity star David Higgins joined Kirkland as the firm’s London co-managing partner.

The firm also hired Weil Gotshal & Manges tax partner David Irvine at the beginning of the year.

Triton and Kirkland declined to comment.