Timothy Alger is leaving his job as head of litigation at Google Inc. to join Perkins Coie as a litigation partner in Palo Alto, Calif.

Alger joined Google in 2008 as deputy general counsel for litigation, and under his watch the company won favorable rulings in several noteworthy cases. In June 2010, a federal judge in New York sided with Google’s YouTube in a $1 billion copyright infringement suit filed by Viacom Inc., and in April 2010, a federal judge in Virginia dismissed a trademark infringement lawsuit filed by language software maker Rosetta Stone Inc.