Boston Bruins general manager Peter Chiarelli announced on Monday that forward Shawn Thornton will not be returning to the team next season.
Thornton, 36, joined the Bruins as an unrestricted free agent in 2007 after spending one season with the Anaheim Ducks.
In 559 career NHL games, Thornton has compiled 906 penalty minutes while contributing 38 goals and 50 assists.
"Today I met with Shawn and I informed him that we will not be re-signing him," said Chiarelli. "I told him that he was one of the most significant acquisitions that we made."
Thornton was selected 190th overall in the seventh round of the 1997 NHL Entry Draft by the Toronto Maple Leafs.
He made his NHL debut with the Chicago Blackhawks during the 2002-03 season.