Protocol
SB Core

Multi-Sig

Native multi-signature support built into the account authority system

Authority Model

SB Chain has native multi-signature support built directly into the account authority system. Multi-sig is not a smart contract — it is a first-class protocol primitive applied to every operation.

Authority LevelPurpose
OwnerHighest level. Used to change keys, recover the account, update authority structure
ActiveUsed for all trading operations, transfers, and day-to-day actions

Authority Structure

Each authority is a weighted set of keys and/or accounts with a configurable approval threshold.

authority {
    weight_threshold: uint32               // total weight required to approve
    key_auths:     { public_key  => weight } // individual key weights
    account_auths: { account_id  => weight } // account-level signers
    address_auths: { address     => weight } // legacy address signers
}

How Multi-Sig Works

  1. Configure the authority with multiple keys or accounts, each assigned a weight
  2. Set weight_threshold to the minimum combined weight required to authorise an operation
  3. Any operation submitted by the account must be signed by a combination whose weights sum to at least weight_threshold
Example: three keys with weights 1, 1, 1 and weight_threshold = 2 requires any two of the three to sign — a standard 2-of-3 multi-sig.

Flexible Configurations

  • M-of-N keys — standard multi-sig (e.g. 2-of-3, 3-of-5)
  • Nested accounts — an account can appear as a signer, enabling multi-sig structures where a team account controls another account
  • Mixed — combine individual keys and accounts as signers in the same authority
  • Asymmetric — different weights per signer (e.g. a senior key with weight 3, junior keys with weight 1)
  • Owner vs Active separation — keep cold keys offline for the owner authority while using separate active keys for daily operations

Key Properties

  • All accounts support multi-sig by default — no conversion required
  • Owner and active authorities are independently configurable and can be updated at any time using the owner key via account_update_operation
  • A compromised active key cannot change the owner authority
  • Multi-sig accounts are fully compatible with all DEX operations — trading, transfers, governance voting