The firm, which has not got a presence in the area, has poached managing partner David Lewis as well as a team of 10 assistants and support staff.
The Lawyer understands Lewis decided to leave Denton Hall because he disagreed with the Wilde Sapte marriage. The merged firm will remain in the region through Wilde Sapte's Tokyo office.
Denton Wilde Sapte international managing partner David Moroney adds Lewis was "disappointed" he was not made head of the Tokyo office.
That role has instead gone to Wilde Sapte's Tokyo managing partner Phil Quirk.
Herbert Smith already has offices in Singapore, Bangkok, Beijing and an associated operation in Jakarta