Crypto firms are upgrading wallets to quantum-proof versions to counter a predicted quantum computing threat that some estimates place as soon as 2030. These wallet-level upgrades are expected to be implemented faster than core blockchain protocol upgrades, enabling custodians and institutional wallets to add post-quantum protections without changing underlying protocols. Industry implementations use post-quantum multi-party computation (MPC) and distributed signing that splits private keys across devices, fitting custodians and institutional wallets, and can also be deployed as a code upgrade that adds a post-quantum signing layer without changing system operation.
Multi-party computation (MPC) is used to move signing operations away from single, reconstructible private keys by splitting private keys across multiple devices or nodes. In MPC-based distributed signing, the signing process generates cryptographic shares on isolated nodes and combines those shares to produce a valid signature without ever reconstructing the full private key. This split-key architecture aligns with custodian and institutional wallet models that distribute key material across infrastructure components. Implementations aim to perform joint signature generation within existing distributed signing systems.
The National Institute of Standards and Technology (NIST) has approved three post-quantum signature algorithms: SPHINCS+, Falcon, and CRYSTALS-Dilithium. Silence Laboratories spent six months evaluating those algorithms specifically for distributed signing systems used by custodians and institutional wallets and added support for distributed signatures using ML-DSA. A central technical challenge identified is MPC friendliness: not every post-quantum scheme supports efficient distributed signing, and that can affect whether a scheme is practical for MPC deployments. Related performance considerations include differences in signature size and computational efficiency, which can lead to fragmentation as different chains or implementations select different schemes.
These technical approaches combine MPC-based distributed signing with selected NIST-approved algorithms and focused evaluations by providers. They represent the core technical considerations for upgrading custody and institutional signing systems.
Custodians and institutional wallets are naturally aligned with multi-party computation (MPC) because they distribute key material across infrastructure rather than relying on a single reconstructible private key. MPC systems split private keys across multiple devices or nodes, enabling distributed signing where cryptographic shares are generated and combined across isolated nodes. Partnerships with companies like BitGo and banks building digital-asset practices reflect this operational model, as those institutions organize signing to prevent keys from sitting in one place. This alignment makes MPC-based approaches compatible with existing custody workflows.
Providers and custodians with existing MPC infrastructure can migrate to post-quantum MPC-based wallets without changing their core infrastructure, as the upgrade can be implemented at the wallet level. Silence Laboratories designed its approach to work within existing MPC systems and to allow an upgrade that does not alter system operation. The wallet-level change is described as a code upgrade that adds a post-quantum-secure signing layer to distributed signing systems. Because the upgrade occurs at the wallet level, users of those custodial services would not need to take action.
The crypto sector is proactively adopting quantum-proof wallets that combine multi-party computation and distributed signing to split private keys across devices and enable joint signature generation without reconstructing keys. This institutional alignment with MPC, reflected in partnerships and custody practices, enables providers to deploy post-quantum upgrades at the wallet level as code changes that integrate with existing MPC infrastructure and require no action from end users.
