Mathieu Schneider - 10 Teams (Montreal, Islanders, Toronto, Rangers, Kings, Detroit, Anaheim, Atlanta, Vancouver, Phoenix)
Speaking of regrettable trades, defenseman Mathieu Schneider had spent eight seasons in Montreal and won a Stanley Cup with the Canadiens in 1993 when he was traded along with Kirk Mueller to the Islanders for Pierre Turgeon and Vladimir Malakhov in April 1995. The trade to Long Island was the first move in what would be many in the back half of Schneider's 21-year NHL career.
After representing the Islanders in the 1996 All-Star Game, Schneider and Wendel Clark were traded to the Toronto Maple Leafs in a deal that landed the Islanders the fourth overall pick in the 1997 NHL Draft (Roberto Luongo) and defenseman Kenny Jonsson. The Leafs traded him in 1998 to the New York Rangers, where he played 155 games for the Blueshirts before being selected by the Columbus Blue Jackets in the 2000 Expansion Draft. He signed as a free agent with the Los Angeles Kings in 2000 and was moved to the Detroit Red Wings for a 1st round pick, 2nd round pick, and two players ahead of the 2003 deadline.
From there, he signed as a free agent with Anaheim and was traded to the Atlanta Thrashers, who dealt him back to Montreal in 2009. Schneider signed as a free agent with the Vancouver Canucks before the 2009-10 season and was dealt for the final time to the Phoenix Coyotes, where he finished his career at the age of 40.