Bernstein says Bitcoin market already priced in quantum risk

Bernstein says Bitcoin’s selloff already reflects quantum risk and that developers still have time to agree on a post-quantum upgrade path.

Bernstein said Monday that Bitcoin’s selloff has already priced in much of the market’s fear around quantum computing, arguing that the threat is real but still manageable rather than an immediate existential risk.

Bitcoin’s (BTC) near 50% drawdown from its $126,198 all-time high in October 2025 is proof that the market has “priced in” several risks tied to a quantum breakthrough, partly thanks to technological progress on zero-knowledge privacy and quantum-proof cryptography that “counterbalance” the AI and quantum acceleration, Bernstein said in a Monday note shared with Cointelegraph.

The note lands two weeks after Google researchers said future quantum computers could break the elliptic-curve cryptography used across many blockchains with fewer than 500,000 physical qubits in some architectures, reviving debate over how quickly Bitcoin needs a post-quantum upgrade path. This research suggested a quantum computer could crack a Bitcoin private key in nine minutes, in a theoretical scenario, which is less than Bitcoin’s 10-minute block production time.

However, Bernstein said Bitcoin core developers have “adequate time” to determine a post-quantum path. Last week, Bernstein predicted that Bitcoin has about three to five years to prepare for a post-quantum security upgrade, Cointelegraph reported on Wednesday.

Bernstein said large institutional holders, including exchange-traded fund (ETF) issuers and corporate treasury buyers such as Strategy, are likely to play a constructive role in any eventual consensus on a post-quantum upgrade.

The note also highlighted the recently introduced BIP-360 proposal and added that slower consensus from Bitcoin developers is seen as responsible behavior when it comes to a $1.5 trillion asset.

BIP-360 is a draft Bitcoin Improvement Proposal that proposes a Pay-to-Merkle-Root output type designed to reduce long-exposure quantum risk by removing Taproot’s key-path vulnerability, though it does not itself add post-quantum digital signatures.

Bernstein said BIP-360 could be implemented as a soft fork for exposed Bitcoin addresses, but added that this would still leave around 8% of the BTC supply in inactive addresses vulnerable to future quantum breakthroughs.

Related: Bitcoiners push for quantum-resistant BIP-360 upgrade as debate heats up

The real challenge of quantum-proofing Bitcoin lies in the societal adoption element of the new standards, not the technical development, according to Arthur Breitman, co-founder of Tezos blockchain.

“The coding work could be done this afternoon,” but Bitcoin holders would still need to migrate to this new standard, Breitman told Cointelegraph during an interview at EthCC 2026.

“If Bitcoin needed to migrate in the next month, they could do it from a technical perspective [...] but they can’t get everyone to migrate their key in a month, Breitman said. “It’s going to take years for people to properly migrate their keys,” he added.

Asset manager Grayscale’s head of research, Zach Pandl, shared a similar view in a research report last Monday. He said Bitcoin’s quantum-proofing challenges are “more social than technical,” provided that its UTXO model does not have native smart contracts and that some address types are not quantum vulnerable.

However, he warned that the community needs to find consensus on how to quantum-proof wallets where the private key has been lost or is otherwise inaccessible.

Magazine: AI has dramatically accelerated the quantum threat to Bitcoin: AI Eye

Source: CoinTelegraph