American grandmaster Hans Niemann has probably cheated in more than 100 online games since 2020, including games with a prize pool. The site Chess.com came to this conclusion in its investigation, comparing Niemann's moves with the moves of chess programs.
Niemann himself has admitted to cheating in online games before, but claims he has never done so in tournaments with prize money.
In addition to comparing moves, Chess.com notes Niemann's too rapid progress in the Elo rating (his rise from 2500 to 2600 points in three months is described as "statistically extraordinary" phenomenon).
The authors of the investigation did not analyze live games at the chessboard, but note that Niemann's six strongest performances in competitions are worth investigating separately.
In September, reigning world champion Magnus Carlsen resigned after two moves against Niemann in the Champions Chess Tour online tournament. He explained this by distrust of the opponent.