Bitcoin developers are weighing a new BIP-361 proposal that could make up to 4 million BTC▼$65,668.00 in old wallets unusable within years.
Crypto developers are weighing a proposal that could make millions of BTC coins effectively unspendable within years in one of the most aggressive protocol changes ever floated for the network.
The draft, known as BIP-361 and authored by developers including Jameson Lopp, a Bitcoin security engineer, outlines one of the most aggressive protocol changes ever suggested for the network.
If activated, the plan would give Bitcoin holders about three years before new transactions to legacy wallets are blocked. It would then set a roughly five-year cutoff, after which old signature types would no longer be accepted. At that point, any BTC left in those wallets would still exist on-chain but couldn’t be moved.
Quantum Risk Drives Urgency
The push is tied to growing concern around quantum computing after Google researchers said recently that breaking Bitcoin’s core cryptography may require far fewer resources than previously thought, potentially shrinking the window for a safe migration.
Read also: Quantum-Proof Bitcoin Without a Fork: Post-Quantum Transaction Model Proposal
That creates a scenario where an attacker could quietly derive private keys and drain funds, potentially without being detected right away.
The BIP-361 proposal tries to get ahead of that by forcing the ecosystem — wallets, exchanges and custodians — to upgrade on a fixed timeline.
Early Bitcoin wallets, including long-dormant holdings from the network’s first years, are among the most exposed. If those coins aren’t moved in time, they could be permanently frozen. For now, though, BIP-361 remains a draft, and there’s no clear timeline for when, or if, the broader community will reach a decision.
Read also: Bitcoin Quantum Risk Is ‘More Social Than Technical,’ Grayscale Says
