StarkWare announced on August 26, 2026, that it had executed what it describes as the first quantum-safe Bitcoin transaction, sending 3.1 BTC using a technique called signature grinding developed by Avihu Levy, head of StarkWare’s applications division. The method is designed to close a known vulnerability: while a Bitcoin transaction waits in the mempool, exposed mathematical data could theoretically allow a sufficiently powerful quantum computer to forge a signature and steal funds.
The process works by rejecting the first valid signature and running through millions of candidates until it finds one that does not expose public key data. It is deliberately computing-intensive and can take hours to produce a single transaction. Because the transaction format is unusual, regular Bitcoin nodes would not process it; it was handed directly to miner MARA, which included it through its Slipstream service for non-standard transactions.
StarkWare emphasized that this is a proof of concept, not a network-wide upgrade. CEO Eli Ben-Sasson compared the situation to passengers on the Titanic, saying the work proves lifeboats exist but more need to be built now. Avihu Levy favors a full protocol-level upgrade to make Bitcoin quantum-safe for all users. The company also warned that a cryptographic break could leave vulnerable coins unable to be spent, causing network-wide paralysis.
Following the announcement, StarkWare’s STRK token climbed about 4.5% to $0.027 before pulling back from that high. The claim remains pending broader independent verification and peer review, with open questions around compatibility with existing UTXOs, signature size, cost, and Bitcoin block-space constraints.
