Coinbase argued this Tuesday (13) that the Bitcoin network should immediately begin preparing its transition to cryptographic systems resistant to quantum computers. In a technical document, the exchange presented recommendations to upgrade transaction security and allow users to gradually migrate their assets, before this technology represents a concrete threat.
The concern mainly involves wallets whose public keys are already visible on the blockchain. In an assessment released in April, Coinbase's advisory council estimated that approximately 6.9 million BTC are in this condition, making them potentially vulnerable to future quantum attacks.
Sufficiently advanced quantum computers could use this information to discover private keys and authorize fraudulent transfers. There is currently no machine proven capable of carrying out this attack against Bitcoin, but the company argues that changes to the protocol and the migration of millions of wallets could take years.
Coinbase, which says it custodies about 5% of all existing bitcoins, considers it essential that the upgrade preserve both the security of individual wallets and the mechanisms used by large financial institutions.
Coinbase proposes gradual migration and prepares its own system for 2027
Among the recommendations is the adoption of flexible structures to incorporate new digital signature algorithms without requiring complete redesigns of the protocol. The company highlighted proposals such as P2MR (BIP-360) and P2TRv2, which could facilitate future cryptographic upgrades.
Another possibility involves wallets with two alternative authorization methods: one based on traditional Bitcoin signatures and another on post-quantum cryptography. This configuration would allow a gradual transition while the community discusses when to restrict the old mechanisms.
The document also establishes an important distinction between protecting active wallets and deciding the fate of abandoned, inaccessible bitcoins or those held in old addresses.
Coinbase argues that these discussions should proceed separately. The absence of consensus on lost coins should not prevent the implementation of new protections, although the handling of these assets remains without a defined solution.
In parallel, the exchange is developing PQ-CoreKMS, a version of its key management system prepared for post-quantum cryptography.
In July 2026, the company set a deadline of approximately one year to make available an automated infrastructure capable of operating with post-quantum signatures, which points to July 2027. Over the following two to three years, it plans to develop more advanced multiparty computation capabilities, technology used to protect private keys without gathering them in a single location.
This timeline, however, applies to Coinbase's internal infrastructure, not to the upgrade of the Bitcoin network. Adoption of the new signatures by the blockchain will depend on development, testing, and consensus among ecosystem participants.
To date, none of the proposals discussed has been established as a definitive solution for the post-quantum migration of Bitcoin.
