In 2004 the British illusionist, Derren Brown, despite being a very poor chess player scored +4 -3 =2 against 9 strong chess players including scoring 2/4 against 4 grandmasters in a simul. Of course it was a blind simul (the players couldn't see each other) with alternating colours where he just copied moves between pairs of boards.

All good, clean fun when performed as entertainment, but what happens when it happens in real life? In a serious competition? What are the sanctions? What can the arbiter do about it? Is it even illegal?

When this was put to Geurt Gijssen in An Arbiter's Notebook his reply was basically nothing!

In my opinion, an arbiter has no possibilities to forbid this behaviour.

Stewart Reuben describes a situation which occurred in an U13 match between England and Sweden about 30 years ago where the Swedish players with white copied the moves made by the English players on the boards next to them and similarly the Swedish black players.

Once the English players realized what was going on one of them, Darren Lee, deliberately lost a piece to see what would happen. The blunder was faithfully copied by the young Swedish player. Eventually the English boys solved the problem by just sitting there until they were in acute time trouble and then blitzed their opponents who didn't have time to continue with their cheating and England ran out 3-1 winners.

Stewart Reuben's suggestion is to make use of article 11.3 a. 

During play  the players  are  forbidden  to make use of  any notes,  sources of information or advice, or analyse any game on another chessboard.

However it is a stretch to describe what is going on as "analysis on another chessboard" and it is unclear if you can actually impose a penalty based on this.

The only solution he could suggest was moving same coloured boards affected to another room or another part of the same room to prevent the copying.

In case you think this sort of thing doesn't happen at the highest level here are 3 games from the round 13 of the 1955 Gothenburg Interzonal, although I suspect no way were any of the black's copying!

[White "Keres "]
[Black "Najdorf, Gothenburg 1955 round 13"]
[FEN "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w - - 0 1"]

1. e4 c5 2. Nf3 d6 3. d4 cxd4 4. Nd4 Nf6 5. Nc3 a6 6. Bg5 e6 7. f4 Be7 8. Qf3 h6 9. Bh4 g5 10. fxg5 Nfd7 11. Ne6 fxe6 12. Qh5 Kf8 13. Bb5 Kg7 14. O-O Ne5 15. Bg3 Ng6 16. gxh6 Rh6 17. Rf7 Kf7 18. Qh6 axb5 19. Rf1 Ke8 20. Qg6 Kd7 21. Rf7 Nc6 22. Nd5 Ra2 23. h4 Qh8 24. Ne7 Ne7 25. Qg5 


[White "Geller "]
[Black "Panno, Gothenburg 1955 round 13"]
[FEN "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w - - 0 1"]

1. e4 c5 2. Nf3 d6 3. d4 cxd4 4. Nd4 Nf6 5. Nc3 a6 6. Bg5 e6 7. f4 Be7 8. Qf3 h6 9. Bh4 g5 10. fxg5 Nfd7 11. Ne6 fxe6 12. Qh5 Kf8 13. Bb5 Ne5 14. Bg3 Bg5 15. O-O Ke7 16. Be5 Qb6 17. Kh1 dxe5 18. Qf7 Kd6 19. Rad1 Qd4 20. Rd4 exd4 21. e5 Kc5 22. Qc7 Nc6 23. Bc6


[White "Spassky "]
[Black "Pilnik, Gothenburg 1955 round 13"]
[FEN "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w - - 0 1"]

1. e4 c5 2. Nf3 d6 3. d4 cxd4 4. Nd4 Nf6 5. Nc3 a6 6. Bg5 e6 7. f4 Be7 8. Qf3 h6 9. Bh4 g5 10. fxg5 Nfd7 11. Ne6 fxe6 12. Qh5 Kf8 13. Bb5 Kg7 14. O-O Ne5 15. Bg3 Ng6 16. gxh6 Rh6 17. Rf7 Kf7 18. Qh6 axb5 19. Rf1 Ke8 20. Qg6 Kd7 21. Rf7 Nc6 22. Nd5 Ra2 23. h3 Qh8 24. Ne7 Ne7 25. Qg5 Ra1 26. Kh2 Qd8 27. Qb5 Kc7 28. Qc5 Kb8 29. Bd6 Ka8 30. Be7 Ra5 31. Qb4

I once did something similar myself. My opponent, white, outrated me by about 200 points but turned up about 30 minutes late. meanwhile I kibitzed the game of a player about 400 points stronger than me who often played one of my favourite openings as black. He got a powerful attack although eventually his opponent neutralized it and then my opponent turned up and I had to concentrate on my game.

I followed the moves I'd seen played on the higher board and was delighted when my opponent unwittingly did the same and I got the same powerful looking attack. At a key moment we ended up repeating moves when my opponent alternately checked me and then defended with the checking piece while I alternately blocked the check and then moved the blocker back into the attack, but still a good result.

  • 3
    Leonard Barden tells the story of how in the 1957 Hastings premier he was white against Peter Clarke in a Ruy Lopez Steinitz deferred where the same moves were played in Keres - Filip shown on the demo board which he could see but which was behind Clarke's back. He started deliberately copying Keres moves and when Clarke got up to look around he realized what was happening and joined in! Keres - Filip was agreed drawn in 16 moves and Barden - Clarke followed suit a few moves later. A modern, angst-ridden example streathambrixtonchess.blogspot.com.es/2009/07/…
    – Brian Towers
    Commented Dec 29, 2014 at 11:00
  • Wow! That's a great example on how to copy from another board to get a disadvantage!
    – David
    Commented Oct 8, 2021 at 9:14
  • I am trying to find the year of a Bundesliga match involving two games McShane vs Shirov and Anand vs X (maybe Bologan ?), where Anand purposefully deviated from his preparation (in a very trendy Svechnikov) to ensure that the two games diverge and McShane couldn't copy his moves (although McShane had no such intention)...
    – Evargalo
    Commented Jun 4 at 11:20
  • Found it ! Teammates Anand and Shirov for Werder Bremen Team facing McShane and Hracek on neighbouring boards, Anand played the inferior 15.Nc2?! instead of 15.Rd1 "because Hracek had already played Rd1 and I didn't want to face Shirov's preparation". McShane clarified later that he didn't plan to copy Shirov anyway, because he considered that would be cheating. chessgames.com/perl/chessgame?gid=1550309 chessgames.com/perl/chessgame?gid=1550308
    – Evargalo
    Commented Jun 4 at 11:32

7 Answers 7


You must realize that no one may figure out a line like that over the board. This variation (up to 8. ... g5 9. Bh4) was quite popular in fifties, and for such an important tournament was obviously heavily analyzed. The Argentinians came well prepared with 10. Nf7. It turned out that Soviets were equally well prepared with 13. Bb5. A teamwork at its best.

The Gothenburg variation was born.


Stewart Reuben's suggestion is to make use of article 11.3 a.

During play the players are forbidden to make use of any notes, sources of information or advice, or analyse any game on another chessboard.

However it is a stretch to describe what is going on as "analysis on another chessboard"

You can debate whether it's "analysis on another chessboard". But if the moves are being deliberately copied from another game, that other game is clearly being used as a "source of information", which is also prohibited. A penalty can certainly be imposed if the arbiter is sure that this is what's happening. If the arbiter suspects but isn't sure, moving the game would probably be a good solution.

Of course, players can play identical moves due to similar opening preparation, so merely having identical boards is not indicative that this is happening (although you'd expect one board to get ahead of the other because not everyone plays at the same pace, even when they're in their opening preparation.) But if a player has the move and, instead of contemplating their position, is looking at an identical chessboard and waits for that player to play, then immediately plays the same move, and that's repeated several times... that would be good enough for me.


This actually happened at the 2019 Isle of Man Grand Swiss tournament which, apart from lots of money, had a place in the Candidates tournament as the first prize. The players involved were elite players, Alexei Shirov vs Yu Yangyi on board 7, and sitting next to them on board 8, Sergey Karjakin vs Alexey Dreev.

The Chief Arbiter, Alex Holowczak, made the decision to move one of the boards after 18 moves.

[title "Shirov vs Yu Yangyi, Karjakin vs Dreev"]
[fen ""]

1. e4 c5 2. Nf3 e6 3. d4 cxd4 4. Nxd4 Nf6 5. Nc3 Nc6 6. Nxc6 bxc6 7. e5 Nd5 8. Ne4 Qc7 9. f4 Qb6 10. c4 Bb4+ 11. Ke2 f5 12. exf6 Nxf6 13. Be3 Qd8 14. Nd6+ Bxd6 15. Qxd6 Bb7 16. g4? c5! 17. Rg1 Ne4! 18. Qe5 Qh4?? (18...O-O!) 19. Bg2 Qxg4+

The tournament was sponsored by Chess.com and so extensive live streaming was available on Twitch. This meant that commentators IM Anna Rudloph and GM Danny King were able to grab the Chief Arbiter for an interview and ask for an explanation which is still available.

Alex Holowczak made it clear that nobody was accused of wrongdoing. For most of the game Karjakin and Dreev were several moves ahead (hence not obvious what was happening) but the last two moves before the separation there was embarrassed looking from one board to the other.

Holowczak: "I saw Yangyi look quite nervous when he looked over to Dreev who had made the move a minute or two before. So, I thought in the interests of everybody feeling comfortable with the game that it was better to move it into the second hall. Then nobody can accuse anybody of anything"

King: "Is it an offence to copy somebody else's moves?"

Holowczak: "N'Ermmm ... I suppose it must be if we think they have copied their moves, but we don't think that. We're not moving them because we think there has been an offence. What we're trying to prevent is any accusation that there might have been an offence"

Very diplomatic.

IM Danny Rensch was less diplomatic when he looked at the games on YouTube. Although he followed Hanlon's razor and attributed what happened (following analysis and then copying blunders) to incompetence rather than malice. Rensch does some nice analysis in his video pointing out the blunders that were mindlessly copied after the first 15 moves of theory.

Once the boards were separated the games swiftly diverged with different results as well as different moves.


In your question you are conflating two different things. The first thing described is your first link about Derren Brown in which he plays as white game A, as black game B, and then, copies every move his opponent makes as white in game B, into game A, and vice versa exchanging colors. this effectively makes Derren just a "telephone" transmitting the moves between boards A and B, so, those 2 guys are playing a game between themselves.

There is a catch: While your clock in the game you are color sorta emulates the game where your oponent is color, in reality it takes you some time, to react to the move played by color and trasmit it into the other board. So you have to be quick, or else, you'll loose some seconds each move, wich if time trouble comes could be lethal, but if there is no time trouble for any of the oponents, then it's all good. So time control matters in this scam.

This is, and should be, highly illegal and frowned upon. Because, for example, rating don't mean anything anymore: if you can find 2 oponents stronger than you, you are guaranteed, without even thinking or investing ANY effort, to have a score 1/2 in this match. Then, your rating goes up undeservedly.

The second thing you described is copying a game that has already had happened in the past. That is totally legal and even good. Top players "replay" opening moves others did in literally all the games, begginers copy the scholars mate, etc. To punish this would be to punish knowledge, which goes against chess wisdom/philosophy. Also note at some point is extremely likely your oponent will deviate soon and it won't be anymore possible to copy anymore. Note this is called: "getting out of book".

  • Isn't the "1/2 guarantee" only true if both strong player happen to always play the exact same moves?
    – David
    Commented Oct 8, 2021 at 9:15
  • @David No, it's a special system, it doesn't work like that. Of course, in practice, it never ever happens, for many reasons, such as being trivially detectable, which would ruin one's reputation, but also it's not that easy to copy the moves on time, and the players will realize and tell the arbiter... But, check out the derren brown thing, to understand it better, it's an old ingenious trick. Commented Oct 8, 2021 at 18:28

Well I think copying should not be a matter of "cheating", because there are huge amount of opening variations and even if you copy some moves the opponent isn't likely to play the same move sequence. And even the opening lines are copied, aren't they? Some grandmaster or master plays the opening sequence (be it long time ago), you like it and play it. It is also a kind of copying but definitely far from cheating.


From Chesslife, July 2016, "The Chess Multiverse"

In http://www.chessgames.com/perl/chessgame?gid=1156906, After the fifth move, "Barden was wondering how to continue at this point when he looked up--and noticed that the same position had appeared on a large demonstration board behind his opponent's back." (http://www.chessgames.com/perl/chessgame?gid=1072644) Before his ninth move, Clarke noticed that his game was following the other and started to copy Filip's moves. "Barden added, on the English Chess Forum Website. The reaction from the spectators and the tournament arbiter 'was just amusement.'" The Keres-Filip game was agreed to a draw after white's 16th move, so the other seven moves play were from the mind's of Barden and Clarke.

Since the coping was for such a short number of moves the argument could be made that they were just following opening theory and the similarity was just a coincidence. Although the use of other sources of information, that is another game was referenced, the arbiter isn't able to make any judgement unless one of the players makes a complaint.

The famous 1955 Gothenburg Interzonal incident is true, but it was the Argentinians who found this opening trap, and they just happen to be able to surprise their Russian opponents at the same time.


Isn't a player allowed to make any legal move on their turn?

If my White position happens by chance to be identical to another board's White position, and that white makes a move and then makes a wincing expression clearly showing it was a mistake, can I avoid that move or would I be using another source of information if I eliminate that move?

Don't put a board next to mine and tell me I can't copy. Or put salt in the wound by saying I can't copy now, but I can copy those moves in future games, including the very next game.

  • 3
    "Isn't a player allowed to make any legal move on their turn?" No, he's not. He is not allowed to get moves, legal or otherwise, from other sources like notes, a computer, his phone, other players, etc.
    – Brian Towers
    Commented Sep 27, 2018 at 9:50

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