1999 Major League Umpires Association mass resignation

The 1999 Major League Umpires Association mass resignation was a labor tactic used by 68 Major League Baseball (MLB) umpires, including 66 members of the Major League Umpires Association (MLUA), the official umpires union at the time. Unable to strike because they had a labor agreement in place at the time, 54 umpires formally resigned by orchestrated letters in an attempt to force negotiations with MLB for a new labor agreement. MLB instead immediately accepted the resignations of 22 umpires and hired new ones. The union membership became fractured on the issue, and 42 of the umpires tried to rescind their resignations, but the MLUA was unsuccessful in retaining the jobs of the 22 umpires and the resignations were seen as final. The incident led to the decertification of the MLUA and the formation of a new union, the World Umpires Association (WUA).

Entering the 1999 MLB season, the union was dealing with disagreements with MLB on a variety of issues. The league sought to make it easier to replace umpires, and proposed a restructuring of the umpiring system; instead of MLUA members answering to the American and National Leagues, MLB wanted them under the control of the commissioner. In addition, MLB wanted changes in the strike zone that umpires called during games, to which the umpires and MLUA leadership objected. The MLUA also had a complaint against the Major League Baseball Players Association, when it released a survey of players, which included umpire ratings, publicly. During the season, there were numerous disputes between umpires and MLB owners. One involved Tom Hallion, who was suspended for three days by NL president Leonard Coleman after bumping a player. Another regarded the amount of pay owed to umpires who officiated the exhibition game between the Baltimore Orioles and Cuban national baseball team.

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