TLDR
- StarkWare completed the first quantum-resistant Bitcoin transaction using a method called signature grinding
- The method adds an “extra lock” to protect Bitcoin holdings without requiring a network fork
- Transactions in the Bitcoin mempool are vulnerable to quantum attacks during the brief window before confirmation
- The process is computing-intensive and can take hours to produce a single transaction
- MARA mined the transaction through its Slipstream service; StarkWare’s STRK token rose about 4.5% after the news
StarkWare has successfully completed what it calls the first quantum-resistant Bitcoin transaction. The company says the breakthrough shows that protecting Bitcoin from quantum computing threats does not require a network fork.
We had a whitepaper and a dream, it’s now a reality.
🚨 The first quantum-safe Bitcoin has been mined 🚨@StarkWareLtd sent 3.1 BTC using @avihu28's Quantum-Safe Bitcoin method. A spend no quantum computer could forge, under Bitcoin's rules as they exist today. https://t.co/cjuIftzzee
— Starknet (@Starknet) August 26, 2026
The method was developed by Avihu Levy, head of StarkWare’s applications division. It uses a technique called signature grinding to protect Bitcoin holdings while a transaction sits in the mempool waiting to be confirmed.
Why the Mempool Is a Risk
When a Bitcoin transaction is in the mempool, it exposes mathematical data that a quantum computer could potentially use to forge a signature and steal funds. This is the window that signature grinding is designed to close.
Signature grinding works by rejecting the first valid signature and instead running through millions of candidates until it finds one that does not expose public key data. The process is deliberately slow and can take hours of computing time.
The transaction sent 3.1 BTC using this method. It was developed to give Bitcoin custodians a quantum-safe spending path that works under Bitcoin’s existing rules.
Because the transaction format is unusual, regular nodes on the Bitcoin network would not process it. It had to be handed directly to a miner willing to accept it outside the normal queue.
MARA mined the transaction through its Slipstream service, which allows non-standard transactions to be included in blocks.
StarkWare Still Wants a Protocol Upgrade
StarkWare CEO Eli Ben-Sasson said the method provides reassurance but is not a permanent fix. He compared the situation to passengers on the Titanic, saying Levy’s work proves lifeboats exist but that more need to be built now.
Levy himself favors a full protocol-level upgrade to make Bitcoin quantum-safe for everyone on the network.
The company says the bigger risk from quantum computing is not simply theft. A cryptographic break could leave vulnerable coins unable to be spent at all, causing paralysis across the network.
The Quantum-Safe Bitcoin method moves from a whitepaper concept to a working implementation with this transaction. StarkWare says it is intended to prepare custodians for the potential arrival of quantum computers powerful enough to break Bitcoin’s current cryptographic protections.
STRK climbed about 4.5% to $0.027 following the announcement before pulling back from that high.
StarkWare is pushing for a permanent solution at the protocol level, saying that the current workaround, while functional, requires special arrangements that most Bitcoin users cannot easily access.
