Bitcoin holders risk losing BTC from BIP-110 fork without replay protection

Developers are warning that this replay attack mechanism means selling the forked coins could result in the loss of real bitcoin, not just the new, potentially worthless, coins. The BIP-110 proposal aims to restrict non-payment data in transactions for a year, requiring miner agreement. While the initial method for agreement is closed, a secondary route involves mandatory signaling starting around block 961,632. However, the actual restrictions on transaction data, which would provide replay protection, are not expected to activate until block 965,664, anticipated in early September.

Until this replay protection is in place, individuals who do not possess the technical expertise to separate the two balances are advised to avoid moving any bitcoin. Bitcoin developer Kevin Loaec highlighted this risk, suggesting that doing nothing is the safest option as unspent coins cannot be replayed. Current miner signaling for BIP-110 is low, around 2.6%, making a sustained split uncertain, but the risk of a replay attack remains if a fork does occur.