A custody operations lead who gets a written client question about quantum exposure has had one honest answer available: point at a developer mailing list and describe an argument in progress. The StarkWare demonstration changes the shape of that answer, because according to Gizmodo the technique asked nothing of the network's consensus rules [1], and Gizmodo frames it as an escape hatch a holder can build now rather than a repair to the network [2].
Opt-in is the mechanism here, and opt-in is also the limit on what it covers. A quantum-resistant spending arrangement covers the coins whose holder signs to move them, while the risk Glassnode measured is a pile of already-exposed public keys sitting still [4]. Bitcoin's ownership proofs run on elliptic-curve signatures, and an exposed public key is the input Shor's algorithm would work on [3]. Roughly 69.8% of issued supply was not in that condition when Glassnode looked [3], so the queue is scoped to a minority of supply, which is the one encouraging number in the set.
The institutional money is sized for research rather than for migration. The July consortium's $15 million over three years works out to about $5 million a year [8][1], set against the roughly $483 billion of exposed coins Gizmodo values at an $80,000 bitcoin price [4], or about 0.001% of that exposed value annually [2]. Coinbase has separately stood up an independent advisory board on quantum computing and blockchain security [9], and Corallo said in February that Blockstream Research and Chaincode have each put resources into what a post-quantum change should look like [12]. None of that funds anyone's signing ceremonies.
Nobody has set a date for when migration has to happen, and the people best placed to set one disagree with each other. The emerging developer view, per Gizmodo, is to have a migration mechanism ready before Q-day rather than rush an emergency change through now [13]. Strategy's Michael Saylor and others have put a serious threat more than a decade out, while Coinbase's research argues preparation has to begin well before the machines can break signatures [10]. Ray Dalio keeps listing quantum computing among bitcoin's technology risks [11].
The sort that helps on Monday has two axes: whether the public key is already exposed on chain, and whether anyone can still sign for the coins. Exposed and signable is the queue, and it is the only box a custodian can shrink without permission from anybody. Exposed and unsignable is the hostage population, with Satoshi Nakamoto's early coins the famous case [7], and it is what the fork argument is actually about, since Corallo's stated aim is to reduce the vulnerable pile enough to "minimize the chance that the Bitcoin community feels the need to fork to burn coins" [5] and he has also sketched a soft fork that would disable vulnerable spending paths, with no settled answer for coins left behind [6]. Unexposed and signable is hygiene, and it can wait behind the first box. The figure worth tracking internally is the share of coins under your control sitting in that first box, because a client will ask for it this year and a fork proposal will assume it later.
