Here are the most notorious cases of cheating in the history of chess

1. Hans Niemann vs. Magnus Carlsen (2022)
The most talked-about scandal in recent years.

 What happened?
During the 2022 Sinquefield Cup, 19-year-old Hans Niemann defeated world champion Magnus Carlsen.
Carlsen then withdrew from the tournament—an unprecedented move—and posted a cryptic message on Twitter suggesting he had been cheated.

“If I speak, I am in big trouble.”
(This is a quote from football coach José Mourinho—implying he knows something but can't say it.)
He suggested cheating, but provided no evidence.
It was the first withdrawal of this kind in his career.
In the following weeks, Carlsen stated openly:

“Niemann has cheated more—and more recently—than he has publicly admitted.”
He added:
“His play was unnatural... I had the impression he knew what I was going to do.”
 Niemann’s response:
“This is ridiculous. Yes, I cheated online when I was 12 and 16 years old. I’ve never cheated in over-the-board games.”
 Evidence:
Chess.com released an 84-page report suggesting Niemann may have cheated over 100 times in online games.
However, there was no proof of cheating in over-the-board play, such as the game against Carlsen.

 Theories:
Absurd speculations emerged, including the idea that Niemann used an anal device to receive Morse-code-style signals during games.
There was no evidence whatsoever to support this.

 The aftermath:
It sparked widespread discussions about security and fair play in chess.

 Hans Niemann’s lawsuit:
Date: October 2022
Who did he sue?

Magnus Carlsen
Chess.com
Hikaru Nakamura (streamer and GM who commented on the case)
The Play Magnus Group
Amount: $100 million
Allegations: Defamation, conspiracy, hindering his professional career.

 Settlement (August 2023):
Chess.com and Niemann announced an amicable resolution.
Chess.com restored his account and allowed him to play again.
Neither side admitted guilt.
Magnus and Hans later played again (!) in an online tournament—without scandal.

 
2. Igors Rausis (2019)
A player caught cheating using a phone.

 What happened?
58-year-old Latvian-Czech grandmaster Igors Rausis was caught during a tournament in Strasbourg.
He went to the bathroom and was using a phone, which is strictly forbidden.
A chess app (engine) was found open on his device.

 Consequences:
FIDE stripped him of his GM title.
He received a lifetime ban.
Rausis admitted guilt and retired from chess.
 
3. Borislav Ivanov (2012–2013)
One of the most suspicious cases ever.

 Who was he?
A Bulgarian player with no international title, rated around 2200 Elo.
Suddenly began beating grandmasters and playing at a 2700+ level (!).
Gained attention after a series of unbelievable results that didn’t make sense.

 Most suspicious game – Zadar 2012:
Tournament: Zadar Open 2012 (Croatia)
Result: 7/9
Drew or beat, among others:

GM Bojan Kurajica (former junior world champion),
GM Ivan Šarić (future European champion).
 The stats were shocking:
His moves matched Stockfish’s top choices 90–95% of the time.
He played like a literal computer.

 Community reactions:
GM Smerdon (Australia):
“If he’s not cheating, he’s the greatest talent in chess history.”
GM Mladen Palac (Croatia):
“It felt like I was playing against a computer.”
 
 Searches and accusations:
Tournament in Blagoevgrad (2013):
Organizers asked Ivanov to remove his shoes, suspecting a device was hidden there.
He refused and was disqualified.

 Suspicions included:
Earpiece + outside help analyzing the game,
A computer hidden in a shoe transmitting signals (e.g., Morse code),
Or another device giving move suggestions.
 
 What happened next?
Ivanov disappeared from the chess scene after 2013.
Later surfaced in local media—as a math teacher, then as a suspect of forging a diploma (!).

Ivanov famously said at a press conference:
“I’m not a computer. I just train a lot.”
 Why wasn’t he formally punished?
He was never caught red-handed—no physical evidence was found.
FIDE never officially suspended him, but the chess world completely rejected him.
 
4. Online Cheaters – Thousands of Cases
Platforms like Chess.com, Lichess ban cheaters daily.

 How do they cheat?
They switch tabs during games and use chess engines.
Platforms use anti-cheat algorithms that analyze:

Move correlation with engines,
Thinking time,
Mouse movement behavior,
Game history.
 Scale:
Chess.com claims to ban tens of thousands of accounts each month,
including premium and high-level accounts.

 
5. Cheating via Live Broadcasts
In some online tournaments, players watched delayed streams with commentators using engines.
One example: A tournament on Chess24 where players benefited from “ghosting”—helpers analyzing in real time.

 
 How are live tournaments protected?
Metal detectors, scanners, disabled Wi-Fi.
Ban on phones, watches.
Players often undergo airport-style checks.