Sources: Seymour dealt to Raiders
In return, the Patriots get a 2011 first-round draft pick, a source told ESPN NFL Insider Adam Schefter.
Seymour, 29, spent the first eight years of NFL career with New England. In that time, he amassed 357 total tackles and 39 sacks in 111 career games. Seymour also has 4.5 sacks in 15 postseason games.
The five-time Pro Bowler and three-time Super Bowl champion matched his career high with eight sacks in 2008.
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