10 and 5 rule

The 10 and 5 rule is a standard clause in the Collective Bargaining Agreement that was first introduced in 1973. It allows any player who is a ten-year major league veteran, including the last five with his current team, to veto a trade to another team. No reason needs to be given and there is no need for the player to have a no-trade clause in his contract.

The clause was introduced following the Flood v. Kuhn court case in which OF Curt Flood opposed having been trade from the St. Louis Cardinals to the Philadelphia Phillies after the 1969 season. Flood refused to report to his new team and sued Major League Baseball (under the name of Commissioner Bowie Kuhn) to have the trade canceled and baseball's antitrust exemption overturned. While Flood lost his court case, the Players Association considered that his opposition was justified and fought to have a clause preventing the unwanted trade of well-established players be included in the next CBA.

Ron Santo was the first player to invoke the clause when he refused to be dealt from the Chicago Cubs to the California Angels on December 5, 1973. Instead, the Cubs had to work out a deal acceptable to Santo - a trade to the crosstown Chicago White Sox, for whom he played the final season of his Hall of Fame career. Other players who have invoked the clause include Steve Rogers and Dennis Martinez.