He started small, working as a help desk guy during his undergraduate days at Princeton. But in recent years Alexander Macgillivray has held some of the key jobs in technology and Internet litigation.

Before joining Twitter, Inc., as its general counsel in September 2009, the Harvard Law School alumnus worked as Google Inc.’s senior product and IP counsel following a three-year stint in Wilson Sonsini Goodrich & Rosati’s Internet litigation group. Macgillivray, 38, was a key lawyer in the Google Books settlement and in Viacom, Inc.’s pending $1 billion copyright infringement suit against Google, so his move to Twitter made big headlines — “Twitter Nabs Legal Eagle from Google,” as The New York Times put it in July 2009.