Bernstein said Bitcoin’s recent selloff already reflects market fears around quantum computing, arguing the threat remains manageable rather than an immediate existential risk.
Bitcoin has fallen nearly 50% from its $126,198 peak in October 2025, with Bernstein noting the decline incorporates concerns over quantum breakthroughs alongside offsetting advances in zero-knowledge privacy and quantum-resistant cryptography.
“The threat is real but still manageable rather than an immediate existential risk,”
Bernstein said in a Monday note shared with Cointelegraph.
The note follows recent research from Google suggesting quantum computers could theoretically break elliptic-curve cryptography with fewer than 500,000 qubits, potentially cracking a Bitcoin private key in under 10 minutes.
Bernstein added that developers still have “adequate time” to coordinate a post-quantum upgrade, estimating a three-to-five-year window for implementation while institutional players are expected to help drive consensus.
The firm pointed to the proposed BIP-360 upgrade as a potential interim solution to reduce quantum exposure, though it warned that roughly 8% of Bitcoin supply in inactive wallets could remain vulnerable even after changes.
Industry figures including Tezos co-founder Arthur Breitman and Grayscale’s Zach Pandl said the challenge is more social than technical, as migrating users to new cryptographic standards could take years despite the relative ease of implementing code changes.
At the time of reporting, Bitcoin price was $74,320.96.