Triple Repetition Draw
In chess there is a “draw by triple repetition” if the same position occurs three times in the game. It doesn’t have to occur sequentially, so long as the same position has occurred three times at any point in the game (no matter how many moves ago).
Triple repetition most commonly occurs with “perpetual check”. There are lots of positions where a Queen can keep checking the enemy King, going back and forth forever. At the third iteration of this, it can be officially drawn by the rule of triple repetition. Note that not all cases of perpetual check end in triple repetition, such as if a Queen is chasing a King all over the board with checks (usually that’s drawn by agreement or drawn by a “no progress rule”).
Not all cases of triple repetition involve perpetual check. There are various situations where it may be necessary for players to repeat moves, or they would otherwise suffer some losing disadvantage on the board. It doesn’t have to be check for a draw by triple repetition to be claimed. Sometimes they can even occur by accident with one player not realizing the position is being repeated.
A draw by triple repetition is not automatic, but must be actually “claimed” by a player. The official procedure in tournaments is quite tricky. The draw can be claimed for either player to move: if the position is repeated already (by the opponent’s last move), or if the player claiming the draw is about to play a move that will result in a repeated position (in which case the player must actually then make that move on the board if the draw request is denied by the adjudicator). Some of the procedural aspects of a draw claim include that it is inherently an offer of a draw, that the clocks must be stopped, that the official referee must be summoned, and then the referee must either allow or deny the claim of repetition.
The requirement for the repetition of the “same position” is also quite restrictive. The “same position” means that it must be the same player to move on all three of the positions. And there must also be the same “castling right” (rarely occurs) and even the same “en passant right” (surely this never occurs).
Related Chess Tactics
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