Article 6: The chessclock
6.1 ‘Chessclock’ means a clock with two time displays, connected to each other in such a way that only one of them can run at one time. ‘Clock’ in the Laws of Chess means one of the two time displays. Each time display has a ‘flag’. ‘Flag-fall’ means the expiration of the allotted time for a player.
6.2.1 During the game each player, having made his move on the chessboard, shall stop his own clock and start his opponent’s clock (that is to say, he shall press his clock). This “completes” the move. A move is also completed if:
6.2.1.1 the move ends the game (see Articles 5.1.1, 5.2.1, 5.2.2, 9.6.1 and 9.6.2), or
6.2.1.2 the player has made his next move, when his previous move was not completed.
6.2.2 A player must be allowed to stop his clock after making his move, even after the opponent has made his next move. The time between making the move on the chessboard and pressing the clock is regarded as part of the time allotted to the player.
6.2.3 A player must press his clock with the same hand with which he made his move. It is forbidden for a player to keep his finger on the clock or to ‘hover’ over it.
6.2.4 The players must handle the chessclock properly. It is forbidden to press it forcibly, to pick it up, to press the clock before moving or to knock it over. Improper clock handling shall be penalised in accordance with Article 12.9.
6.2.5 Only the player whose clock is running is allowed to adjust the pieces.
6.2.6 If a player is unable to use the clock, an assistant, who must be acceptable to the arbiter, may be provided by the player to perform this operation. His clock shall be adjusted by the arbiter in an equitable way. This adjustment of the clock shall not apply to the clock of a player with a disability.
6.3.1 When using a chessclock, each player must complete a minimum number of moves or all moves in an allotted period of time including any additional amount of time with each move. All these must be specified in advance.
6.3.2 The time saved by a player during one period is added to his time available for the next period, where applicable.In the time-delay mode both players receive an allotted ‘main thinking time’. Each player also receives a ‘fixed extra time’ with every move. The countdown of the main thinking time only commences after the fixed extra time has expired. Provided the player presses his clock before the expiration of the fixed extra time, the main thinking time does not change, irrespective of the proportion of the fixed extra time used.
6.4 Immediately after a flag falls, the requirements of Article 6.3.1 must be checked.
6.5 Before the start of the game the arbiter shall decide where the chessclock is placed.
6.6 At the time determined for the start of the game White’s clock is started.
6.7.1 The regulations of an event shall specify a default time in advance. If the default time is not specified, then it is zero. Any player who arrives at the chessboard after the default time shall lose the game unless the arbiter decides otherwise.
6.7.2 If the regulations of an event specify that the default time is not zero and if neither player is present initially, White shall lose all the time that elapses until he arrives, unless the regulations of an event specify or the arbiter decides otherwise.
6.8 A flag is considered to have fallen when the arbiter observes the fact or when either player has made a valid claim to that effect.
6.9 Except where one of Articles 5.1.1, 5.1.2, 5.2.1,
6.10.1 Every indication given by the chessclock is considered to be conclusive in the absence of any evident defect. A chessclock with an evident defect shall be replaced by the arbiter, who shall use his best judgement when determining the times to be shown on the replacement chessclock.
6.10.2 If during a game it is found that the setting of either or both clocks is incorrect, either player or the arbiter shall stop the chessclock immediately. The arbiter shall install the correct setting and adjust the times and move-counter, if necessary. He shall use his best judgement when determining the clock settings.
6.11.1 If the game needs to be interrupted, the arbiter shall stop the chessclock.
6.11.2 A player may stop the chessclock only in order to seek the arbiter’s assistance, for example when promotion has taken place and the piece required is not available.
6.11.3 The arbiter shall decide when the game restarts.
6.11.4 If a player stops the chessclock in order to seek the arbiter’s assistance, the arbiter shall determine whether the player had any valid reason for doing so. If the player had no valid reason for stopping the chessclock, the player shall be penalised in accordance with Article 12.9.
6.12.1 Screens, monitors, or demonstration boards showing the current position on the chessboard, the moves and the number of moves made/completed, and clocks which also show the number of moves, are allowed in the playing hall.
6.12.2 The player may not make a claim relying only on information shown in this manner.