The team announced the move Tuesday. Cooper is the first free agent the Raiders have signed this offseason who did not play for the team last year.
Cooper does have a history in Oakland. He was a sixth-round pick by the Raiders in 2001 and spent three seasons with the team. He has played for Dallas, San Francisco and Arizona since leaving the Raiders.
He spent the 2008 season on injured reserve for the Seattle Seahawks and played in the United Football League last season.
He has 8½ sacks in 78 career games.