Collusion

Collusion is intentional cooperation between two or more people to cheat, deceive other participants, or distort a competition. Chess.com's Competitive Events Policy defines it as intentional cooperation to cheat or deceive other players. In chess it can include sharing unauthorized help during a game, coordinating outcomes, or working together to benefit an account or participant artificially.

A related concept is match-fixing: agreeing on or attempting to influence the result in advance instead of competing normally. Online regulations of the International Chess Federation (FIDE) treat deliberate manipulation of chess competitions, including match fixing, as cheating. Lichess also prohibits arranging wins to inflate an account's competitive rating artificially.

Not every agreement between players is collusion. A draw offered and accepted in good faith can be entirely legal when event rules permit it. The distinction is the purpose to deceive or manipulate. Collusion may include engine assistance if an accomplice relays software-generated moves, but it can also exist without engines. Anti-cheating measures are intended to address both situations.