Multisignature (Multisig)
Multisignature (Multisig) is a cryptoasset management mechanism in which executing a transaction requires multiple independent digital signatures.
Unlike models based on a single private key (such as MPC), multisig involves several distinct private keys, each controlled by a separate participant.
Multisig operates at the blockchain protocol or smart contract level and requires prior deployment to the network, including payment of the associated transaction fees.
Basic Operating Principle
Multisig follows a threshold logic model (e.g., 2-of-3):
- multiple independent private keys are generated,
- a required confirmation threshold is defined,
- a transaction can only be executed once the required number of signatures is collected.
In networks that support smart contracts (such as Ethereum), multisig is implemented as a dedicated smart contract that must be deployed on-chain.
After deployment:
- A transaction proposal is initiated.
- Signatures are collected off-chain.
- Once the threshold is reached, a decision is finalized.
- The result (an approved transaction or a rejection) is broadcast to the network.
- The smart contract verifies the signatures and executes the operation.
Thus, the coordination logic occurs prior to on-chain publication, while the blockchain records only the final outcome.
Architectural Characteristics
Key features of multisig include:
- each participant controls an independent private key,
- keys are neither divided nor combined,
- signatures are created independently,
- the smart contract validates both the number and authenticity of signatures.
Unlike MPC, multisig genuinely relies on multiple separate keys.
The multisignature wallet address is a distinct on-chain entity and differs from a standard single-key address.
Examples of Multisignature Solutions
Common multisignature solutions include:
- Gnosis Safe
- BitGo Multisig
- Electrum Multisig
- Casa Multisig
These solutions differ in terms of automation, user interface, and infrastructure design, but the core principle remains the same: multiple independent signers must authorize a transaction.
Integration with Hardware-Based Security
Multisig does not dictate how private keys are stored.
Each private key may be held:
- in a software wallet,
- in a hardware wallet,
- within an HSM.
Using hardware wallets or HSMs for each participant significantly enhances overall security.
Multisignature schemes can therefore be combined with other storage and protection models.
Advantages of Multisig
Multisig provides:
- distributed control among multiple participants,
- protection against a single point of compromise,
- transparent governance logic at the blockchain level,
- formalized approval procedures for organizational use.
This model is widely adopted in:
- investment funds,
- decentralized autonomous organizations (DAOs),
- corporate treasuries,
- joint investment structures.
Limitations and Risks
Multisig also entails certain limitations:
- the need to deploy and fund a smart contract,
- potentially higher transaction fees (depending on the network),
- increased complexity in participant management,
- risk of asset lockup if the required number of keys is lost,
- potential vulnerabilities in smart contract code.
Furthermore, if a sufficient number of participants are compromised (e.g., 2-of-3), the protection mechanism fails.
Difference Between Multisig and MPC
| Criterion | Multisig | MPC |
|---|---|---|
| Number of keys | Multiple independent keys | One key (distributed into shares) |
| Logic level | Blockchain-level | Signature-level cryptography |
| Requires smart contract | Yes (in most networks) | No |
| Transaction format | Specialized structure | Standard transaction |
| On-chain visibility | Transparent | Indistinguishable from regular transaction |
Multisig implements distributed control through blockchain-level rules, whereas MPC achieves it through cryptographic computation.
Conclusion
Multisig is a distributed cryptoasset management model based on the use of multiple independent private keys.
It provides a transparent and formalized transaction approval mechanism at the blockchain level.
When integrated with hardware wallets and HSMs, multisignature architectures become a powerful tool for corporate and institutional digital asset governance.
Within the cryptoasset storage ecosystem, multisig represents a technologically mature and widely adopted solution for distributed control.