Multisig Wallets

A multisig (multi-signature) wallet requires M-of-N signatures to authorize a transaction. For example, a 2-of-3 wallet needs any 2 out of 3 registered devices to sign before a transaction can be broadcast. This eliminates single points of failure and enables shared custody.

When to Use a Multisig Wallet

Multisig wallets are suited for:

• Shared custody — Multiple parties must approve transactions (e.g., business partners)
• Enhanced security — Losing one device doesn’t compromise funds
• Organizational treasuries — Board approval requirements for spending
• Redundant backups — Multiple devices mean multiple recovery options

Custody Models

Sigvault supports three multisig custody configurations:

Custodial Multisig

All keys are system-managed. The service controls multiple signing keys and can authorize transactions without user devices. Useful for automated or institutional workflows.

Non-Custodial Multisig

All keys are held on user-controlled hardware devices. Sigvault only stores public keys and coordinates the signing ceremony. Users retain full control.

Collaborative Multisig

A mix of system-managed and user-managed keys. For example, in a 2-of-3 setup, the user holds 2 hardware devices while the system holds 1 backup key. This provides both user control and a recovery path.

How It Works

1. Device Registration — Each key holder registers their hardware device
2. Wallet Creation — Define the threshold (M-of-N) and assign devices to each key slot
3. Receiving — Addresses are derived from all public keys combined in a multisig descriptor
4. Sending — A PSBT is built and routed to each required signer. Once M signatures are collected, the transaction is finalized and broadcast

Wallet Templates

Sigvault provides pre-configured multisig templates:

Template	Configuration	Use Case
Family Joint Wallet	2-of-3	Family members share custody
Small Business Treasury	2-of-2	Owner + accountant dual approval
Enterprise Treasury	3-of-4	Executive committee approval
DAO Treasury	3-of-5	Governance structure

Creating a Multisig Wallet

1. Register devices for each key holder
2. Navigate to Wallets and select Create Wallet
3. Choose a multisig template or configure a custom setup
4. Set the threshold — how many signatures are required (M)
5. Assign devices to each key slot (N total)
6. Review and confirm

Signing Ceremony

When a transaction requires multiple signatures:

1. The transaction initiator builds and submits the PSBT
2. Sigvault tracks which signatures are still needed
3. Each required signer connects their hardware device through the desktop app
4. Each device displays the transaction for verification and signs independently
5. Once the threshold is met (M signatures collected), the transaction is finalized
6. The fully signed transaction is broadcast to the network

The signing process doesn’t need to happen simultaneously — signers can sign at different times.

Considerations

• Coordination overhead — Multiple signers must be available (though not at the same time)
• Threshold selection — Too low reduces security; too high increases the risk of lockout
• Backup planning — Consider what happens if one key holder becomes unavailable
• Device diversity — Using different hardware wallet brands reduces risk from firmware vulnerabilities