BitMEX Research has put forward an alternative to freezing dormant Bitcoins vulnerable to quantum attacks, instead recommending a wait-and-see strategy centered around a “canary fund” and quantum bounty.
In a proposal released Thursday, the firm outlined a soft fork that would only trigger a full freeze of at-risk coins if it is definitively proven that a quantum computer capable of stealing Bitcoin actually exists.
The approach introduces a “canary” Bitcoin address generated using a Nothing-Up-My-Sleeve Number (NUMS) — a cryptographic method where the private key is unknown but the address remains theoretically spendable by a sufficiently powerful quantum computer.
Users could send BTC to this address as a bounty, effectively encouraging any entity with quantum capabilities to demonstrate them by spending from it. If that happens, it would act as proof of a real threat, automatically activating the freeze mechanism.
This proposal serves as an alternative to the recently suggested BIP-361, which called for freezing dormant, quantum-vulnerable Bitcoin to prevent potential theft. That proposal faced strong backlash from parts of the community, with critics labeling it “authoritarian” and “confiscatory.”
Under BitMEX’s “canary watch state,” older coins would remain spendable as long as no quantum attack is detected via the canary fund. Participants contributing to the fund could use multisignature setups and withdraw their BTC at any time.
The proposal also includes a safety window, allowing certain quantum-vulnerable transactions to proceed even after the five-year deadline suggested in BIP-361, though with temporary restrictions on spending outputs.
“While this approach adds complexity and risk, given how controversial any coin freeze is, mitigating the impact of the freeze using this type of system may be worth consideration.”
BIP-361 co-author Jameson Lopp has described the proposal as a preliminary concept rather than a finalized plan for activation, framing it as a contingency idea.
“I know folks don’t like it. I don’t like it myself. I wrote it because I like the alternative even less,” he said in a post on X on Wednesday.
Speaking to Cointelegraph, Lopp added that the proposal is essentially a “rough sketch” aimed at addressing the risk of a potential supply shock if quantum computing advances to a stage where a post-quantum signature scheme gains consensus for integration into Bitcoin.
