K&L Gates LLP is an American multinational corporation law firm based in the United States, with international offices in Asia, Australia, Europe, the Middle East, and South America. Its namesake firms are Kirkpatrick & Lockhart, a Pittsburgh-based firm founded as Kirkpatrick, Pomeroy, Lockhart & Johnson in 1946, and Preston Gates & Ellis, a Seattle firm founded in 1883 whose prominent partners included William H. Gates Sr., the attorney, philanthropist, and father of Microsoft co-founder Bill Gates. Kirkpatrick & Lockhart merged with Preston Gates in 2007 to form K&L Gates, LLP.