Bitcoin Universe · Model 09

The multisignature vault

Shared control: coins that move only when enough keyholders agree. Configure the vault, approve with individual cosigners, lose keys, and see what a recovery really needs.

Simulated cosigners
Arrangement
required 2 of 3

Who approves

    Recovery

    A multisig backup is every cosigner's seed plus the configuration: all public keys, the number required and the script type. With a lost cosigner and no configuration, the vault's address can no longer be rebuilt.

    Compare arrangements

    Lost keys survivedStolen keys survivedSpend cost per input

    On chain

    Approvals, retracted bolts, the required count and an open vault Lost keys Simulated cosigners

    The vault is P2WSH script multisig with sorted keys (sortedmulti). Its witness script and address are computed for real; the cosigners' keys come from one public test phrase, which real cosigners must never share. Key-aggregation and threshold schemes (MuSig2, BIP327; FROST, still emerging for Bitcoin) reach similar policies with a single on-chain key and signature, at the cost of interactive signing.