What is a Multi-Signature Wallet?
A multi-signature (multisig) wallet is a smart contract wallet that requires a minimum number of private key signatures (e.g., 2-of-3, 3-of-5) to authorize a transaction, distributing control across multiple parties.
WHY IT MATTERS
Multisig is the gold standard for organizational crypto security. Instead of one person holding the keys to the treasury, 3 of 5 team members must agree to move funds. This prevents single points of failure — one compromised key isn't enough to steal funds.
Safe (formerly Gnosis Safe) is the dominant multisig implementation, securing over $100B in assets. It's battle-tested, modular, and supports arbitrary threshold configurations. Most DAOs, protocol treasuries, and enterprises use Safe for fund management.
For agent wallets, multisig can serve as a governance layer. The agent treasury might be a 2-of-3 multisig where the agent has one key but needs at least one human co-signer. Or, multisig can manage the policy configuration that controls the agent's spending.
HOW POLICYLAYER USES THIS
PolicyLayer complements multisig by adding programmable, automated controls. While multisig requires human signers for every transaction (slow for agents), PolicyLayer enables autonomous operation within pre-approved limits — with multisig governance for policy changes.