I. GENERAL RULES AND PLAYING CONDITIONS

1. Contestants: The World Othello Championship shall be held annually to determine the World Othello Champion and the World Othello Team Champions. Every nation may present up to three contestants, with the exception of the hosting country (see II.2). Before the tournament, the tournament organisers may, in case of serious doubt, request a player to present his credentials as a representative of his country.

2. The Officials: The host country shall arrange for the services of a chief referee and other tournament officials. There shall be sufficient officials to provide a scorer for each tournament game. The chief referee shall be responsible for the running of the tournament, including the pairings process and adherence of players and spectators to the rules described herein, and shall be the arbiter of any disputes arising during the tournament. A decision of the chief referee may, in exceptional circumstances, be appealed to the Council of Federations: see V.

The chief referee shall appoint table officials (see IV.2), who will transcribe the games. If possible, the tournament officials should arrange for the four semi-finalists to receive transcripts of their prospective opponents' games in time to prepare for the third day of competition.

3. Playing Conditions

3.1 The Tournament Room: The host country shall endeavour to provide the contestants with good playing conditions. The tournament room shall be quiet and well lit. (Indirect lighting is preferred because direct light reflects off the shiny surfaces of the playing discs, making it difficult to distinguish their colour).

3.2 Consultation: During the course of the game, a player may not consult any notes or exchange information of any kind with another person, with the exception of a tournament official.

3.3 Smoking: It is strictly forbidden to smoke in the tournament room.

3.4 Mobile phones: Mobile phones brought into the tournament room must be switched off. If someone forgets to do so and their phone happens to ring in the tournament room, they must not answer the call but must immediately switch the phone off.

4. Spectators: Spectators are permitted in the tournament room at the discretion of the chief referee. Spectators and other contestants are permitted to observe a game in progress, but must not interfere in any way with conduct of the game. In particular, observers must refrain from making any comments on the game, or in any way distracting the players or the table referee. However, if another player detects any irregularities in the game, he may mention them to the chief referee or one of his assistants.

II. TOURNAMENT FORMAT

1. Overview: There will be three days of tournament play. The aims of the first two days of competition are:

a) To select four players who will compete on the third day for the individual title.

b) To decide the World Othello Team Championship.

The third day of competition will be organised as follows:

a) There will be two semi-finals, one played between the first and fourth-ranked players from the first two days of competition, and the other between the second and third-ranked. These are to be the best of three-games matches
b) There will be a final, organised as a best of three-game match between the winners of the two semi-finals, and a one game play-off for third place between the two losing semi-finalists.

2. Playing System: During the first two days of the tournament, the system used will depend upon the number of contestants in the tournament as set out below:

a) Up to 8 players: A double Round Robin.
b) 9-14 players: A single Round Robin.
c) 15-24 players: A modified Swiss system.
d) More than 24 players: An unmodified Swiss system.

See II.5 for further details. If a Swiss system is to be used, seven rounds will be played on the first day and six on the second.

If there would otherwise be an odd number of players, the host country may enter an additional player in the tournament to prevent the introduction of a bye. This player shall be designated as the country's fourth player before the beginning of the tournament.

If the host country has already entered three players, the points gained by the designated fourth player shall not count for the team championship.

However, the fourth player shall have the same status as the other players as regards the individual championship, and, in particular, shall have a full right of access to the semi-finals and final.

3. Individual Final Ranking List (IFRL): At the end of the first two days of competition, the officials will draft the Individual Final List Ranking (IFLR) following the procedure set out below:

3.1 Provisional List: A provisional list is first drawn up, players being arranged in order of number of points scored in the tournament - one point will be awarded for each win and half a point for each draw; in case of ties, the Mixed Brightwell System (MBS) will be used to separate the contestants (see appendix A).

If the fourth and fifth-ranked players in the provisional list have the same number of points, they will play a play-off game. In this game, the fourth-ranked player shall have the choice of colour and shall be declared the winner if the game is drawn.

3.2 Final List: The IFRL is the same as the provisional list with two modifications:

a) If a play-off game was necessary as in II.3.1, the winner of that game is placed fourth in the IFRL and the loser fifth.

b) Any players not ranked among the top four and having the same number of points are declared equal.

4.Team Final Ranking List (TFRL) The final ranking list used to determine the World Othello Team Champion will be drafted as follows: The officials will calculate for each team the sum of the points scored by its members, and the ranking list will be drawn up according to this sum. (If the host country has provided four players, the points scored by the designated fourth player will not be taken into account.) In case of a tie for first place, the country with the greatest number of games between members of its team shall be declared the champion. If two or more teams are still tied for first place, the team having the top player in the IFRL will take preference. In case of a further tie, the team whose second-ranked player is higher in the IFRL will take preference. In case of a further tie, the tied teams will be declared equal.

5. Pairings when a Swiss system is used

5.1. First round

The pairings for the first round shall be determined as follows:

- The players are divided into Group A, those who have played in at least one semifinal of the previous ten World Othello Championships, and Group B, all other players.

- Two players are chosen at random, one from Group A and the other from Group B. They are paired against each other, with the player from Group A assigned black.

- This is repeated, with the player from Group A assigned alternately black and white, until one of the two groups is empty.

- The remaining players are paired by random draw.

5.2. Second and subsequent rounds

In determining the pairings for the second and subsequent rounds in a Swiss system, the following rules should be followed, in decreasing order of priority:

i) Two players from the same team cannot play against each other in the last two rounds.

ii) If an unmodified Swiss system is used, two players who have already played against each other cannot be paired together again. If a modified Swiss system is used, two players who have played against each other twice cannot be paired together.

iii) The two players paired together should have the same number of points. If this is not possible, the difference should be minimal.

iv) In a modified Swiss system, if possible, players who have already played against each other should not be paired together again.

v) Players should tend to play black and white the same number of times during the tournament. If this is not possible, the difference should be minimal.

vi) A player who has already "floated up" should "float down", and a player who has already "floated down" should "float up".

vii) Players should alternate colours from round to round.

6. Withdrawals: If a player withdraws from the tournament, he may not re-enter. In particular, he may not qualify for the semi-finals or final. However, his score at the time of his withdrawal will be entered in the IFRL and be taken into account in the TFRL. A player who has withdrawn will not be considered for the purposes of pairing rounds after his withdrawal, and instead a dummy player called "BYE" will be introduced into the pairing process. See also Appendix A for the effect of a withdrawn player on the calculation of the MBS.

III. SEMI-FINALS AND FINAL

1. Best of Three-Game Matches: The higher-ranked player in the IFRL shall have choice of colour for the first game of the match.

Each player shall be awarded one point for each win and a half point for each draw in the match.

Colours shall be reversed for the second game. If a player wins both the first and second game of a match, then that player shall be declared the winner and a third game shall not be played.

Choice of colour for the third game, if necessary, shall be awarded to the player having the greater number of discs in the first two games. In the case of a tie, the higher ranked player shall have choice of colour.

At the end of three games the player having more points in the match shall be declared the winner. If after three games the two players have the same number of points, the total number of discs in the three games shall be used to determine the winner. In case of a further tie the higher ranked player in the IFRL shall be declared the winner.

2. Semi-Finals: At the beginning of the third day of competition, the four top players in the IFRL will compete in the semi-finals. Each semi-final match will be a best of three-games match.

The two winners of the semi-finals will advance to the final.

The top-ranked player in the IFRL will play against the fourth-ranked player, and the second-ranked player will play against the third-ranked player.

3. Play-Off For Third Place: The two losers in the semi-final will play a single play-off game for third place. The higher ranked player in the IRFL will have the choice of colour and will be awarded third place if he wins or if the game is a draw. The two winners of the semi-finals will advance to the final.

4. Final: The final will be a best of three-games match. The winner will be awarded the title of World Othello Champion.

IV. CONDUCT AND SCORING OF INDIVIDUAL GAMES

1. Time Limits: Clocks will be used to time all tournament games. During the first two days each player shall have 30 minutes to complete all his moves in each game. During the semi-finals, each player shall have 35 minutes per game. In the final, each player shall have 40 minutes per game. In the play-off for third place, each player shall have 35 minutes. If for any reason these time limits cannot be applied, games should never be played with less than 25 minutes for each player per game.

2. The Table Official: For each tournament game, the chief referee shall assign one of the tournament officials to be the table official, who shall be responsible for making a transcript of the game, observing the rules of Othello and ensuring the smooth running of a game.

Before the beginning of the game, the table official shall make sure that both players have enough discs to complete the game. It is the official's duty to regulate the clock and place it on the right of the player with the black discs (unless both players agree to do otherwise).

During the game, the table official should attempt to make a transcript of the game without requiring the contestants to announce their moves. The record keeping process must never be allowed to interfere with the player's concentration.

If, during the game, a player is left without discs, the table official shall arrange for a sufficient number of discs to be transferred from the player's opponent. To do that he is allowed to stop the clocks for the time required.

3. Objects on the Board: No objects of any kind may be placed on the board with the exception of those Othello discs forming the position and the one Othello disc used by the player to carry out his move.

4. The Move: A player commits himself to a move if he touches the board with his hand or with a disc, with the apparent intention of moving to a given square. In this case, provided the player has a legal move to that square, he must move to the first square he touches, and may not change his mind and move instead to a different square, even if his opponent authorises him to take back his move. The purpose of this rule is to prevent an indecisive player from distracting his opponent or obstructing his opponent's view of the board. A player shall not be bound by this rule, if in the opinion of the table official, he touched the given square unintentionally.

Once a player has committed himself to a move, he is bound to turn over all of the captured discs. He must do this using one hand only, and then use the same hand to press his clock. If, having played a move, a player forgets to press his clock, the table official should tell him to do so.

5. Illegal Moves:

5.1 Procedure: The scorer is present to enforce the Rules of Othello. An error in the play of a move which has just been played but not yet answered may be brought to the attention of the table official by either player, by the chief referee or by one of his assistants. Once the table official notices, or is informed of such an error, he shall adopt the following procedure:
a) Restart the clock of the player who committed the error.
b) Correct the error himself, and
c) Restart the clock of the player whose turn it is to move.

5.2 Accepting the Position: Only the most recent move is subject to hallenge. When a player commits himself to a new move, he tacitly accepts the board position as it is, and neither he nor the official can later seek to correct a previous error.

5.3 Unreadable Position: The players must play their moves and centre the discs so that the position is clearly readable.

If, in the opinion of the table official, the position becomes unreadable, he should take any action to correct it (including stopping the clocks and playing through the transcript). He may also invite the chief referee to impose some penalty on the offending player.

6. Time Defaults: A player forfeits the game unless he can make his final move, flip all the appropriate discs, and stop his clock before the flag on his clock falls. If a player's flag falls, he loses the game and his opponent is awarded a win regardless of the position of the board.

The defaulting player is given two extra minutes. The game is then continued with the true final score standing, save that the non-defaulting player is guaranteed at least a 33-31 win. If the defaulting player's flag falls a second time, the game is scored 64-0. If the flag of the non-defaulting player falls, he too is given an extra two minutes, and the true score stands, unless his flag falls a second time. In this last case, the game is scored as a 33-31 win for the non-defaulting player.

7. Defective Clock: If, in the course of the game, the clock in use is found to be defective, the table official shall summon the chief referee, who will take whatever action he deems appropriate.

8. Scoring: At the end of the game, if both players have completed their moves in the allowed time, the winner is the player with the greater number of discs of his colour on the board at the end. The official score of the game will be determined by counting up the discs of each colour on the board, counting empty squares for the winner.

In the event of a draw, the score will always be 32-32. If one player defaults, the scoring is carried out as in IV.6 above.

A player should not resign a game before it is finished, if he does, the official score shall be 64-0 in favour of his opponent.

V. THE COUNCIL OF FEDERATION

1. Composition: Each National Othello Federation (or National Association of Othello Players) may mandate one person to represent it in the Council of Federations.

2. Meeting: The Council of Federations may be called at any time (including in the course of the World Othello Championship) at the request of one third of its members, or during the World Championships, at the request of the chief referee.

3. Quorum: The quorum for the Council of Federations shall be six. The Council may not legislate if fewer than six members are present.

4. Postal Votes: The Council may take by mail any decision it has the power to make in the course of a meeting.

5. Powers of the Council:

5.1 Overview: The Council may legislate on any subject of its choice pertaining to the game of Othello. On any matters except those covered by 5.2 and 5.3 below, normal voting procedures apply and a motion is carried if it has the support of more than half of the members present.

5.2 Removal of the Referee: The Council has the power, in extreme circumstances, to remove the chief referee at the World Championships and replace him with another person. To secure the removal of the referee requires the support of two-thirds of the members present.

5.3 Modification of Rules: The Council has the power to modify the present Rules for the World Othello Championship. To secure such a modification requires the support of two-thirds of the members present.

5.4 Others Powers: The Council has the power to overturn a decision of the chief referee, it may mandate a person to speak in the name of the Council. It may also appoint committees and transfer to them part of its powers.

VI. ENFORCEMENT OF THE RULES

1. Overview: In order to enforce both the rules of Othello and the World Championship Rules, the chief referee (and only he) may impose penalties on a player or on a spectator.

In imposing penalties, the chief referee should adjust the severity of the penalty to the severity of the offence and never penalize a non-offending player.

2. Penalties: The chief referee may impose the following penalties on a player or on a spectator:

a) Removing time from an offending player's clock and/or giving additional time to his opponent's clock.

b) Changing the final score of a game to the benefit of the offending player's opponent.

c) Declaring the game to be a draw or awarding the game to the offending player's opponent.

d) Expelling temporarily or definitively from the tournament room a player or a spectator.

e) Expelling a player from the tournament.


APPENDIX A

The Mixed Brightwell System (MBS)

1. Overview: The Mixed Brightwell System (MBS) is a method of breaking ties in Othello tournaments run with the Swiss system. It is also applicable to Round Robin tournaments, where it is equivalent to disc-count. Essentially this system is a combination of Strength-of-Opposition and disc-count.

2. The Constant C: MBS depends on a constant C, which is a weighting for the relative importance of Strength-of-Opposition and disc-count. For the World Championships, assuming that they are run either as a Round Robin or as a 13 rounds Swiss system, C will be set equal to 6.

3. The Brightwell Quotient (BQ): After the end of the tournament, the tournament officials will evaluate, for each player involved in a tie, the BQ. This is calculated as follows:

a) If any of the player's opponents have withdrawn in the course of the tournament, ignore any such games for the moment. Also, if a player has been paired against "Bye", leave out such a game.

b) Calculate the total number of discs scored by the player in all games not covered by a) and add C times the sum of points scored in the tournament by all of the players opponents, except those who have withdrawn.

c) For each game against an opponent who has withdrawn, and each bye received, add 32 plus (C times the player's own tournament score) to the result calculated in b). The number resulting is the player's BQ.

4. Resolving Ties: If two players have the same number of points in the tournament, the tie shall be resolved in favour of the player with the higher BQ. If two players have the same number of points and the same BQ, the tie shall be resolved favour of the player with the better disc count. In case of further tie, it shall be resolved by the flip of an Othello disc.