King, who joined Shearman from Linklaters in 2003, was responsible for developing Shearman’s City M&A and capital markets practice. His departure leaves Shearman’s London corporate practice with four partners and no head.
King is known for his big-ticket work, particularly for German corporates such as banks Depfa and Dresdner.
At Weil, which is renowned for its private equity practice, he will work in a team that includes M&A partner Ian Hamilton.
Weil managing partner Mike Francies said: “Peter’s one of a small number of English M&A lawyers who’s very highly regarded across the market by bankers and corporates alike. This is a great opportunity for the London office and the firm.”
Shearman London managing partner Anthony Ward said the firm would name a replacement corporate chief in due course.
A number of high-profile London corporate partners have left in the past few years. Jonathan Coppin joined Hogan & Hartson in 2006 and Adrian Knight joined Skadden Arps Slate Meagher & Flom in 2005.