Signata Identity V2 Proposal

Identity Register

The Signata Identity register is an essential piece of the identity lifecycle, especially in relation to Soubound NFTs, as it provides the overarching lifecycle management of an identity as a whole in addition to any rights/soubound NFTs that may be held by it.

Identity Creation

The first iteration of the Signata Identity register provided a robust model for establishing an mutating an identity on-chain, but suffered from a few drawbacks:

  1. The 3-key approach of "identity" (id_key), "delegate" (delegate_key), and "security" (security_key) keys is too complex for non-technical users to understand.

  2. The id_key key being different from the delegate_key key, but the delegate_key key being (typically) the connected web3 wallet was a confusing model for users.

  3. The need to generate and manage these three keys from a custodial perspective was difficult, as the users would need to use a dedicated dApp rather than being able to be integrated with other dApps.

  4. Some mutation events required digital signatures to be created from the Delegate wallet, which would throw warnings in wallet software that it was a high risk signature to perform (due to a superseded implementation of eth_sign vs. personal_sign)

  5. Delegation could only be against a single address, and not support delegation to services or other trusted individuals.

The proposal for Version 2 is to modify the identity register as follows:

  • Consolidate id_key and delegate_key together to be represented as a single id_key.

  • Establish a delegation mapping against the id_key record, and on creation assign id_key as it's own delegate.

  • Allow the id_key to add or remove delegations to itself. The id_key will be unable to remove itself as a delegation.

  • Lock, Unlock, Destroy, and Migrate events can be performed by any delegated address.

  • An address can be assigned as delegate for multiple id_keys, allowing service providers to centrally manage identities on-chain.

  • The security_key will be removed to reduce complexity. The security_key was originally serving the purpose of an alternative means of identity mutation overrides, but this functionality can be inherited through delegation to a separate address.

The creation of the id_key will not be possible by a delegate - it must always originate from the transaction signer to ensure only the key holder consents to the identity creation. This does not exclude a service provider for creating an identity on-behalf of a user, but they will also be required to generate and retain the private key material (and provide that to the user) to retain full control of the identity.

Identity Mutation

The identity mutation events defined in Signata V1 will still be retained. These are:

  1. Lock

  2. Unlock

  3. Destroy

  4. Migrate

Whilst these states do not remove the on-chain representation of the identity, they still provide tools for service providers to be able to provide alternative control flows for the active state of an identity.

For the id_key, it will retain the ability to perform all mutation events. For delegate addresses, the rights of which mutation event they can perform will be defined by the id_key (for example, they may be permitted to lock and unlock but not destory or migrate the identity).

Soulbound Rights

Signata Rights were an early implementation of what later became known as Soulbound NFTs. This implementation was founded on enterprise identity lifecycle management concepts with the custody of the identity instead held by the creator (as opposed to a 3rd party).

Functionally, these rights still serve the majority of Soulbound NFT requirements, but require updates to meet the additional requirements to become "soulbound-complete" in their utility.

The following headings detail the intended standards implementations for the next version of Signata Rights.


ERC-5192 is an extension of EIP-721. It proposes a minimal interface to make tokens soulbound using the feature detection functionality of EIP-165. A soulbound token is a non-fungible token bound to a single account.


ERC-6150 is an extension to EIP-721. It proposes a multi-layer filesystem-like hierarchical NFTs. This standard provides interfaces to get parent NFT or children NFTs and whether NFT is a leaf node or root node, maintaining the hierarchical relationship among them.

As Signata NFTs are heirarchical in nature, this standard will be considered for replacing the structures for authority-driven


ERC-6147 is an extension of ERC-721. It separates the holding right and transfer right of non-fungible tokens (NFTs) and Soulbound Tokens (SBTs) and defines a new role, guard with expires. The flexibility of the guard setting enables the design of NFT anti-theft, NFT lending, NFT leasing, SBT, etc.

This standard will be considered for implementation to introduce expiration modifiers to Signata Rights. This will be useful for rights such as "proof of KYC" where regulatory requirements require an individual to complete KYC processes periodically. The ability to update this attribute will be held by the administrator of the right.


ERC-5484 defines an interface extending EIP-721 to create soulbound tokens. Before issuance, both parties (the issuer and the receiver), have to agree on who has the authorization to burn this token. Burn authorization is immutable after declaration. After its issuance, a soulbound token can’t be transferred, but can be burned based on a predetermined immutable burn authorization.

Rights attributes

Each Signata NFT bears a "schema" definition, which is the same definition held by every right issued underneath that schema.

The schema owner, upon issuing an NFT right, will be additionally able to define custom data against individual rights. This can be in the form of a URI to an externally hosted definition that provides additional metadata attached to the right, or data to be stored and consumable on-chain.

Migration Strategy

For identities and rights issued against V1 contracts, migration contracts will be provided for converting them into V2 rights. These contracts will be provided for Signata-issued rights, but any 3rd party rights issuers will be required to deploy their own migration contracts if desired.

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