Glossary
MPC
A cryptographic technique that splits a private key into shares held by different parties, so signing requires cooperation without any party ever holding the whole key.
MPC has become the institutional default for custody because it removes the single point of compromise without putting a multi-signature scheme on chain. Signing looks like an ordinary single-signature transaction.
For controls purposes the questions are the same as any quorum arrangement: who holds shares, what threshold is required, where backups live, how a leaver is removed, and whether any single operator could reconstruct enough shares.
Where this comes up
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