14 min ago3 min readBitcoin holders risk losing real BTC if they sell coins from possible BIP-110 fork. (Shutterstock)SummaryA planned Bitcoin fork tied to the controversial BIP-110 proposal could create duplicate balances on two chains, tempting holders to sell the new coins for what looks like free money.Because both chains would initially accept identical transactions, selling the forked coins could trigger a replay attack that also spends the seller’s real bitcoin on the main chain.Developers warn that, without built-in replay protection until at least early September, the safest course for non-experts is to avoid moving coins during the potential split.Bitcoin holders stand to lose real BTC this weekend by trying to sell coins from a fork that may not even be worth anything.Here is how it goes. Bitcoin may split into two chains in the next few days. If it does, everyone who holds bitcoin ends up holding the same balance twice, once on each chain. Then someone offers to buy the new coins at an unusually good price. They look like free money, so selling them can seem like an easy win.But take the deal and the buyer can take the seller's bitcoin too. Both chains initially accept identical transactions — so a transaction signed to send the fork coins can also be broadcast on bitcoin. The buyer receives the same amount in actual BTC at the same destination.This is called a replay attack. The safest move for anyone who does not know how to separate the two balances is to leave the coins alone.How selling a fork coin can cost a holder real bitcoin. (Shaurya Malwa/CoinDesk)A replay does not drain the wallet. Only the coins put up for sale move, and they leave as real bitcoin rather than the fork version, with a transaction fee paid on both chains.Bitcoin developer Kevin Loaec, who flagged the risk on X this week, said large holders could be targeted first. Doing nothing will be a safer option, he stated, as coins that never move cannot be replayed because there is no signed transaction to copy.⚠️IMPORTANT⚠️In the next couple of days, a new shitcoin will fork off Bitcoin. It is a big security risk for people who just believe they will get an "airdrop" and want to sell it, to get more bitcoin.I will write more about it, but here is the TLDR: 👇— Kevin Loaec 🧙‍♂️🐟 (@KLoaec) August 6, 2026