56
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Why did this legendary game of Carlsen vs Nakamura not trigger threefold-repetition after move 5?
While the position might seem like it has been reached 3 times at that point, that is actually only the second time they have reached that position because the first time they were in this position, ...
- 829
46
votes
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Why do GMs repeat moves instead of offering a draw?
A repetition giving the opponent the opportunity to claim a draw is a de facto draw offer but not a de jure draw offer.
What does that mean? Well the "de facto" part means that in practice ...
- 99.9k
19
votes
Why do GMs repeat moves instead of offering a draw?
In many top level tournaments you are not allowed to offer a draw before a certain number of moves are played (often 30 or 40). The purpose of such a rule is to prevent very quick draws.
However, one ...
- 3,646
16
votes
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Does threefold repetition take into account the side to move?
You quote an extract from the FIDE Laws of Chess which includes the simple instruction "see Article 9.2" yet you don't bother to "see Article 9.2" where your question is answered -
9.2.1 The game ...
- 99.9k
16
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Rules: Is this position a draw?
This is a better question than it seems at first glance.
Intuitively it seems possible to claim a draw, since the position appears to have occurred three times.
However, according to a strict ...
- 5,040
14
votes
Accepted
Programming three-fold repetition for my chess engine
Threefold-repetition is about a position (not moves) occurring three times. Those positions do not have to be reached by the same moves.
Also (as this also seems to be confused sometimes) it is ...
- 20.9k
13
votes
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What if threefold repetition occurs in WCC 2018?
Draw by mutual agreement is not allowed before move 30. But a draw by threefold repetition can be claimed at any point if it occurs.
- 16.6k
13
votes
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Does threefold repetition apply in a rapid game?
TL;DR: Claiming draws based on threefold repetition or the fifty-move rule is possible in rapid and blitz games as well. Contrary to RemcoGerlich's answer, it is not strictly necessary to record the ...
- 1,789
12
votes
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What is the order of actions in chess under FIDE rules?
The FIDE Laws of Chess provide some guidance.
Rule 6.2.1 says you must move the piece before hitting the clock:
During the game each player, having made his move on the chessboard, shall stop his ...
- 19.9k
12
votes
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Meaning of the phrase "the same player has the move"
In short, it means that either both positions must be "white to move" (white's turn) or both positions must be "black to move (black's turn). If the pieces are in the same places, but ...
- 781
11
votes
Accepted
Does permanent loss of castling rights reset three fold repetition?
According to the FIDE Laws of Chess:
9.2.2 Positions are considered the same if and only if the same player has the move, pieces of the same kind and colour occupy the same squares and the possible ...
- 99.9k
10
votes
Accepted
50-move rule: FIDE wording seems weird
Hi thanks for the question!
Yes this is what FIDE are saying. If you are about to play the 50.0th move of the sequence, or to cause a position to occur for the third time, then you need to claim ...
- 13.4k
10
votes
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Can you claim a draw, after the position has changed, if threefold repetition occurred earlier?
(I consider the FIDE rules to be the "the rules of chess" and this answer is only about them)
No, you cannot claim. In fact your right to claim ends as soon as you touch a piece.
Here's what ...
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9
votes
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FIDE threefold repetition and possible moves
Hi I have clarified this over the years with the senior FIDE International Arbiter at the time, Stewart Reuben, who is busy now writing the definitive book on the History of the Laws of Chess.
You ...
- 13.4k
9
votes
Accepted
Threefold repetition: what's the minimum number of pieces and/or material points required?
4 pieces is the minimum, and is attained by this position though Black has the option of trading Q for N to a bare-king draw:
[Title "Draw by perpetual check or insufficient material"]
[FEN &...
- 8,294
8
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Why don't engines show explicitly that a certain move takes to a threefold repetition (instead of just showing 0.00)?
It's easy enough to make the engine say it's 0.00 because of a 3-fold repetition. If you look at the relevant part of Stockfish's code, they are basically if statements that return a particular value ...
- 28.3k
7
votes
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Rules: How does right to castle and en passant get considered for the purpose of calculating a threefold repetition?
You have identified the correct rule governing these situations. 9.2.2 is the relevant clause that applies; 9.2.2.1 and 9.2.2.2 are just clarifications of this rule.
So to answer your queries:
1) ...
- 5,040
7
votes
Accepted
What is the longest possible sequence of double checks?
I am pretty sure I could make this last longer, but here is already a sequence with 25 unforced consecutive double-checks without promoted pieces.
[FEN "8/8/8/Rp2p3/3kP1N1/2N3pB/1Q5B/K3R3 w - - 0 ...
- 16.6k
7
votes
How long can a player hold off a draw by the 50-move rule?
The answer is trivially the starting position -
[fen ""]
This exact question hasn't been asked before (I think) but it has been answered here. Here is the relevant part of that answer -
...
- 99.9k
6
votes
How did this game end in a draw?
There was a three-times repetition. Note that only the position needs to be repeated, it is not necessary that the moves leading to the position are the same. The position occurred first after move 58,...
- 1,939
6
votes
Programming three-fold repetition for my chess engine
Although @user1583209 is on the right track. His approach would only work for a chess GUI but too slow for a chess engine. Modern engines only check for the last few moves, they won't go all the way ...
- 22.6k
6
votes
Rules: How does right to castle and en passant get considered for the purpose of calculating a threefold repetition?
I think that your question is an excellent one. @Remillion, @itub and @SmallChess have answered it already. I believe that I mostly—perhaps wholly—agree with their answers, so now I would ...
- 4,569
6
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Making an inferior move to get out of threefold repetition?
Could this theoretically go on forever in a game with time increment?
No, because the arbiter would step in and declare the game drawn after the fifth repetition of the position.
According to the ...
- 99.9k
6
votes
Accepted
How long can a player hold off a draw by the 50-move rule?
I interpret the following
White will play as long as possible, and not want to lose. Black will claim a draw as soon as possible, if not win
as meaning that Black does not help (i.e., Black tries to ...
- 901
6
votes
Why do GMs repeat moves instead of offering a draw?
Often, Grandmasters need to reach the 40-move mark. This standard time controls gives them 30 extra minutes if this milestone is reached. Often times, they will play very similar moves just to get ...
- 387
6
votes
What is the need for repetition rules given the 50 & 75 move rules?
are the (optional) threefold-repetition rule and the (mandatory) fivefold-repetition strictly necessary?
Yes, they are necessary. Something which players sometimes forget is that arbiters are people ...
- 99.9k
5
votes
Rules: Is this position a draw?
It's a repetition draw, claimable by either side (black on the previous move).
If you believe that "commencing the game" is something different from "having and playing the move" ...
- 51
5
votes
Threefold repetition in view of castling rights
This is dealt with explicitly in article 9.2.2 -
9.2.2 Positions are considered the same if and only if the same player has the move, pieces of the same kind and colour occupy the same
squares ...
- 99.9k
5
votes
Threefold repetition in view of castling rights
This seems to be an omission in law 9.2.2.2:
9.2.2.2 a king had castling rights with a rook that has not been moved, but forfeited these after moving. The castling rights are lost only after the ...
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