MPC wallet

Multi-party computation (MPC) lets several parties compute something together without any of them seeing the others' inputs. For wallets, the private key is split into shares held by different machines or parties. To sign, they run a protocol that produces a normal signature, and the full key never exists anywhere.

Compared with other approaches:

• vs. multisig: MPC produces one ordinary signature, so it works on any network and looks like a normal transaction. Multisig needs the network to support it and shows several signers on-chain.
• vs. enclaves: MPC spreads trust across share holders; an enclave keeps the whole key in isolated hardware and can prove what code runs there.
• The protocols are complex, and their implementations have had serious bugs, so audits matter.

On Valtu

Valtu doesn't use MPC. Keys are held whole inside hardware enclaves, and the enclave enforces your approvals and proves its code with remote attestation. The backup is split with Shamir secret sharing. The comparison is in custodial infrastructure or self-custody.