There are many Exit Scams, Ponzi Schemes and Rug Pulls in the world of Cryptocurrencies. It must be remembered that, apart from Rug Pulls (in DeFi), Scams and Ponzi Schemes are as old as time (and not the prerogative of the Crypto world). Basically in a Scam the founders run away with the money, a Ponzi Scheme promises unsustainable income paid with the money of new investors who sign up and pay the old members (until the system collapses), finally a Rug Pull is the removal of liquidity (essentially the native token of the platform is dumped and exchanged for stablecoins, ETH, BNB, etc leaving investors with a worthless token). In this article I will not talk about fraudulent or non-fraudulent bankruptcy (FTX, BlockFi, Celsius, Hodlanut) or alleged Hack/Scam (Mt.Gox) but about scams on centralized investment platforms or in DeFi. Obviously there are a myriad of other Scams and Ponzi Schemes it would be impossible to mention them all.

ONECOIN
OneCoin is considered one of the largest crypto Ponzi schemes in history, having defrauded investors of billions of dollars by promising investors returns on their cryptocurrency investments.
It was founded by Ruja Ignatova in Bulgaria, the scheme raised a total of $4 billion before its collapse. Ignatova disappeared in October 2017 without leaving a trace and is wanted by US authorities for fraud and conspiracy. If arrested and convicted, she faces up to 20 years in prison. After Ruja Ignatova's disappearance, her brother Konstantin Ignatov took the reins but was arrested in 2019 and later pleaded guilty to fraud and money laundering.

BITCONNECT
BitConnect was a cryptocurrency Ponzi scheme that stole $2.5 billion from its investors in 2017-2018.
It promised unsustainable returns on investments, claiming to use a trading bot and lending platform to generate profits. The scheme relied on recruiting new investors to pay off previous investors, without any actual revenue generation. Classic of Ponzi Schemes. BitConnect coin $BCC was listed on exchanges and its price increased, attracting more investors. However, exchanges later delisted $BCC. The website was shut down and the founders disappeared with the funds.

PLUS TOKEN
This Chinese crypto platform stole $2.25 billion of its investors (14.8 billion yuan) between May 2018 and June 2019, promising high returns for referrals and investments. The value of the stolen coins has since increased, with losses estimated at nearly $11 billion. The team fled to Cambodia but were subsequently arrested by Chinese authorities in June 2020. Chen Bo and 15 other people were sentenced to prison terms (ranging from 2 to 11 years) and fines (ranging from $100,000 to $1 million), placing an end to one of the largest crypto scams in China.

THODEX
Thodex which was a Turkish cryptocurrency exchange was founded in 2017 and disappeared in April 2021 with investor funds worth over $2 billion. Founder Frauk Fatih Özer claimed it was a hacker attack and then disappeared into thin air. In 2021, Turkey investigated him for fraud, arrested his employees and seized their assets.

WOTOKEN
WoToken was a cryptocurrency trading platform that promised investors high returns through algorithmic trading bots and referrals but it turned out to be a Ponzi scheme (as often happens in these cases). As of May 2020, he had defrauded more than 700,000 people out of $1.1 billion in cryptocurrency. Four men, including the co-founders, were sentenced to prison terms (up to 9 years).

AFRICRYPT
Two South African brothers disappeared with $3.6 billion in BTC. The two said that the platform they ran had suffered a hacker attack. It actually turned out to be an Exit Scam.
It is possible that, in planning the huge scam, they drew inspiration from the story of Johann Steynberg, CEO of Mirror Trading International, who disappeared after deliberately causing losses of around 589 million dollars to the detriment of hundreds of thousands of users.

QUADRIGACX
This Canadian exchange saw approximately 145 million dollars disappear into thin air. The peculiarity is that the founder Gerald Cotton died suddenly following a trip to India and is said to have faked his death. Some cold wallets on the exchange suddenly "woke up" after his alleged death.

BIGGEST RUG PULL/EXIT SCAM IN DEFI
-AnubisDAO ($60 million): memecoin where 60M in ETH vanished in about 24 hours. The project founded by an anonymous team, without a website and whitepaper, claimed to be a fork of Olympus DAO

-Meerkat Finance ($31 million): Hack or Rug Pull

-Stable Magnet ($27 million): Exit Scam. Quite an elaborate scam given that the explorer had been manipulated making the code appear legit. The funds were then drained from the smart contract via a backdoor

-Luna Yield ($10 million): Rug Pull occurred in just 2 days for this yield optimizer on the BNB Chain. The stolen funds were then laundered with Tornado Cash)

-Squid Token ($3.38 million): Honeypot/Rug Pull. Token inspired by the TV series "Squid Game" which included some elimination challenges where, due to game theory, it was not possible to sell the token until the final challenge

-Evolved Apes ($2.7 million): Creator disappeared with funds earned from NFTs

-Typhoon ($2.7 million): Rug Pull on the BNB Chain

-SaveTheKids ($2 million): Scam promoted by influencers

-SnowdogDAO (Million Dollars): Rug Pull on Avalanche

-Mutant Ape Planet (Amount not disclosed): creator disappeared with the funds earned from NFT (the imitative collection Bored Ape, the founder then arrested, had created another Rug Pull in the past: Crazy Camel Club)

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