StarkWare Executes First Quantum-Safe Bitcoin Transaction on Mainnet

StarkWare has executed what it calls the first quantum-safe Bitcoin transaction on mainnet. The transaction, made by StarkWare researcher Avihu Levy, uses a method called Quantum-Safe Bitcoin (QSB) to protect certain BTC transfers from a future quantum attacker without changing Bitcoin's consensus rules.

The QSB method relies on signature grinding, which involves computing power spent offchain searching through candidate transactions until the transaction hash itself has the structure required to function as a valid signature. This approach avoids exposing public keys and prevents a future quantum attacker from deriving private keys.

The computation required for one QSB transaction is estimated at several hundred dollars, and StarkWare notes that this method cannot protect coins whose public key was already exposed before the protection process begins. Approximately 6.04 million BTC had visible public keys in May, putting roughly 30% of issued supply inside the longer-term quantum-risk set.

The QSB transaction reached a miner directly through MARA Slipstream, which accepts nonstandard Bitcoin transactions that still comply with consensus rules. StarkWare engineer Tomer Giladi helped bring Levy's April research into a working transaction.