Per Soxprospects
Player Options Explained
Governing Rules. Options are governed by Rule 11 of the Major League Rules.
Overview. In general, a team may only send a player in the minor leagues for three seasons after that player is added to the team's 40-man roster. Each of those years is considered an "option year." Thus, a player is said to have three "options" or "option years." Once a player has burned all three options, that player may generally not be sent to the minor leagues without first being designated for assignment, clearing waivers, and accepting an outright assignment.
Minor League Contract. Prior to being placed on a team's 40-man roster, a player is not on optional assignment, but instead just on minor leage contract. Options are not burned in seasons before the player is on the 40-man roster.
Burning Options. Once the player has spent twenty days on optional assignment in a given season, that player's "option year" will burn at the end of that season. However, it is important to note that during an option year, the club is free to option the player up to five times that season, while only burning one "option" for that season. If a player spends less than twenty days on option in a given season, the option does not burn for that season.
Fourth Option Year. Players are eligible for a fourth option season if they have been optioned in three seasons but have not yet amassed five full seasons of professional service time. This is rare.
Ten-Day Rule. A club may not recall an optioned player until ten days of the season have passed since the optioned player reported to the minors, unless one of the following conditions applies: (a) the player is replacing a player placed on the disabled list or the bereavement list; ( the affiliate’s minor league season, including playoffs, has concluded during the 10-day period; or © the optioned player is being assigned to the active list of another MLB club.