(Renton, WA) -- Marshawn Lynch's retirement from the Seattle Seahawks is official. The team says the star running back has been placed on the reserve/retired list. SeattlePI.com says it's not clear whether he's submitted his retirement papers to the NFL. Lynch, who's 30-years-old, made his intention to retire known, via Twitter, during the Super Bowl on February 7th, but had not submitted his retirement paperwork as of last week.