Herbert Smith Freehills' (HSF) head of advocacy Ian Gatt QC has resigned from the firm to join Stewarts Law as a partner.

Gatt joined legacy Herbert Smith in 2005 from Littleton Chambers to launch the firm's advocacy unit, alongside 11 Stone Buildings' Murray Rosen QC.

Rosen left HSF in 2014 and returned to the Bar, joining 4 New Square. Following Rosen's resignation, HSF hired Tom Leech QC from Maitland Chambers to replace him. Leech will now co-lead the London practice alongside disputes partner Adam Johnson.

In a statement, HSF said: "We can confirm that Ian Gatt QC is retiring from the partnership. We thank him for his contribution to the firm and wish him well for the future. We will continue to invest in our market-leading practice, both by way of nurturing our own talent and significant lateral hires where there is a client demand."

Following Gatt's resignation, the firm's London advocacy unit now comprises eight lawyers, including Leech and Johnson.

Gatt's departure is the latest in a spate of recent exits from the Anglo-Australian firm, following Allen & Overy's hire of London finance partner Nick Bradbury last week, and banking heavyweight Malcolm Hitching's move to Ropes & Gray.

Other recent partner departures include Paris disputes head Isabelle Michou, who is leaving for Quinn Emanuel Urquhart & Sullivan, while last month a 10-partner Asia-Pacific team resigned to launch an Australia practice for White & Case.

However, the firm has also made a number of additions to its partnership this year. In March, HSF hired Gabrielle Wong as a partner in its London finance practice. Wong joined from Shearman & Sterling, where she was a counsel. Meanwhile, this May the firm hired Baker & McKenzie's EMEA M&A chair Soenke Becker for its Duesseldorf office.

Earlier this month, HSF announced that it was phasing out its joint CEO leadership structure, with the global partnership council putting forward Mark Rigotti to take on the post alone. He was confirmed as its sole CEO last week.