Trapdoor tokens are a type of scam ERC-20 token that allows users to buy but prevents them from selling by embedding logical bugs and/or owner-only features in their smart contracts. These tokens have cost investors billions of US dollars on Uniswap, the largest decentralized exchange on Ethereum, from 2020 to 2023.

*How Trapdoor Tokens Work:*

1. *Token Listing*: Scammers list a Trapdoor token on a decentralized exchange (DEX) and create an exchange pool paired with a high-value token.

2. *Token Buying*: Investors buy the Trapdoor token by transferring the high-value token to the pool.

3. *Token Selling*: The scammer prevents investors from selling the token by triggering a malicious code or smart contract feature.

4. *Fund Retrieval*: The scammer withdraws all tokens from the exchange pool, including high-value tokens invested by users ¹.

*Red Flags to Watch Out For:*

- *Unusually Low Liquidity*: Legitimate tokens typically have consistent and reasonable liquidity proportional to their number of holders.

- *Suspicious Transfers*: Abnormal transfer patterns, such as a large number of addresses receiving the token without corresponding liquidity.

- *High Sell Tax*: Tokens with unusually high sell taxes may be indicative of a Trapdoor scam ².

*Examples of Trapdoor Scams:*

To avoid falling victim to Trapdoor scams, it's essential to verify contract addresses, monitor token metrics, and beware of unofficial channels. Always prioritize caution and conduct thorough research before investing in any cryptocurrency🤔