Carlsen and Niemann
Magnus Carlsen (left) has accused Hans Niemann of cheating in over-the-board games, plunging world chess into chaos. There's no evidence yet, but Niemann's admission of cheating in online games had only fanned the flames of the row. Image Credit: Vijith Pulikkal/Gulf News

Hans Niemann, the 19-year-old American chess player at the heart of cheating allegations that have rocked the chess world, on Thursday filed a lawsuit in U.S. District Court in Missouri accusing online chess platform and world champion Magnus Carlsen of defamation and collusion, among other infractions.

Niemann is seeking $100,000,000 in damages.

The lawsuit depicts an alleged conspiracy between the popular online chess platform and Carlsen to bar Niemann from professional competition in retaliation for Niemann's defeat of Carlsen, the world's No. 1 player, last month at the St. Louis-based Sinquefield Cup.

Niemann "brings this action to recover from the devastating damages that Defendants have inflicted upon his reputation, career, and life by egregiously defaming him and unlawfully colluding to blacklist him from the profession to which he has dedicated his life," the lawsuit said.

After Niemann's upset, Carlsen hinted that wrongdoing had occurred.

Niemann, a 19-year-old grandmaster, subsequently said he had cheated in matches on when he was 12 and 16 years old — but insisted he had not since then. Carlsen later accused Niemann of having "cheated more — and more recently—- than he has publicly admitted."

Niemann banned

In early October, released a 72-page report saying Niemann "likely cheated" on its site more frequently than he has publicly acknowledged, and Niemann was banned from the site and online events.

At the same time, said its investigation failed to turn up an abundance of "concrete statistical evidence" that Niemann cheated in his win over Carlsen.

Niemann's lawsuit suggests Carlsen wielded his influence as a five-time world champion in a way that has "destroyed Niemann's remarkable career in its prime and ruined his life."

A Norwegian grandmaster, Carlsen won his first world championship in 2013, and later co-founded Play Magnus the same year. Play Magnus began as a chess app which mimicked Carlsen's playing style at various stages of his life, but has since evolved into a company that offers an online playing site and a book publishing outlet. In August, Play Magnus accepted an acquisition offer by worth nearly $83 million.

The lawsuit describes that acquisition as a move that will "monopolize the chess world," and adds that the partnership inspired's alleged collusion with Carlsen "to blacklist [Niemann] from chess," as and Play Magnus "collectively comprise the majority of FIDE-sanctioned chess tournaments."

In the wake of Carlsen's accusations, the lawsuit said, Niemann has had tournament invitations revoked and an upcoming match against 17-year-old German grandmaster Vincent Keymer canceled. It also said Niemann "cannot obtain employment as a chess teacher at a reputable school."


The lawsuit also names Japanese American grandmaster Hikaru Nakamura,'s most popular Twitch streamer with 1.5 million followers. Nakamura is accused of acting in collusion with Carlsen and by posting videos which it said amplified Carlsen's cheating allegations against Niemann.

"By design, this sudden ban, at the precise time that Carlsen accused Niemann of cheating against him, added instant credibility to Carlsen's false allegations and suggested that they were true. Otherwise, there would be no reason for to suddenly ban Niemann immediately after he defeated Carlsen," the lawsuit claims.

"To bolster this unprecedented joint ban, which effectively blacklisted Niemann from professional chess, [grandmaster Hikaru] Nakamura leveraged his platform as's top streamer and credibility as a top chess player to engage in an all-out blitz of defamatory accusations to further confirm that Carlsen accused Niemann of cheating and to make it appear that those accusations are true." executive Danny Rensch, the final defendant named in the lawsuit, is accused of issuing "defamatory press releases, and leaked defamatory 'reports' to prominent press outlets, falsely accusing Niemann of lying in his post-match Sinquefield Cup interview regarding his use of a 'chess engine' in a handful of recreational online games when he was a child," actions which it said further bolstered Carlsen's "false" claims.

Per the BBC, lawyers for said the allegations found in the lawsuit had "no merit." In a statement to Polygon,'s lawyers noted that "Hans confessed publicly to cheating online in the wake of the Sinquefield Cup, and the resulting fallout is of his own making."

"As stated in its October 2022 report, had historically dealt with Hans' prior cheating privately, and was forced to clarify its position only after he spoke out publicly. There is no merit to Hans' allegations, and looks forward to setting the record straight on behalf of its team and all honest chess players."

Carlsen has yet to publicly comment on the lawsuit.