ERC-6147: Analysis of Semi-Mandatory NFT Property Separation Standard

On March 7, 2023, the Ethereum Improvement Proposal EIP-6147 officially entered the final version (Final) status. This standard is an extension of ERC-721, aimed at separating the ownership and transfer rights of NFT and SBT, and introduces a new role "Guardian" with a settable expiration time (Guard). This innovation makes applications such as anti-theft, lending, leasing of NFTs, as well as SBT, more flexible.

Background

A major pain point of NFTs is the lack of liquidity. This issue arises not only from the NFT protocols themselves but is also closely related to how to enhance the actual use value of NFTs. Currently, NFTs face two main problems:

1. Property coupling: High-value NFTs tend to be used as a safe haven, leading to inconvenience. For example, when lending NFTs, it is necessary to transfer the NFTs to the lending contract, resulting in the owner losing the ability to use the NFTs during the lending period.

2. Existing property separation schemes are difficult to control in terms of mandatory nature: proposals such as ERC-4907 and ERC-5058 face challenges in balancing the degree of mandatoriness.

ERC-6147 Operation Mechanism

Guard role

ERC-6147 defines a role called Guard(, which includes the guardian address and expiration time. Only the current owner of the NFT or an authorized address can set the Guard. Guard information can be queried through the guardInfo method, and it will automatically expire after the set time.

![Interpretation of the latest Final ERC-6147: A minimalist semi-mandatory NFT property separation standard])https://img-cdn.gateio.im/webp-social/moments-defb8f4e51869ee996ce467b7fde5ea0.webp(

) Guard's permissions

1. Forced Transfer Rights: For NFTs that have a Guard set, only the guard address can perform transfer operations.

2. The original holder retains the right of possession but loses the right of transfer.

3. The Guard can transfer the guard rights using the changeGuard method.

![Interpretation of the latest Final ERC-6147: A minimalist semi-mandatory NFT property separation standard]###https://img-cdn.gateio.im/webp-social/moments-8e992e191f2263857a2c65baade8a108.webp(

) Guard's restrictions

1. Guard cannot set up automatic deduction authorization.

2. The Guard cannot set Approve to prevent unauthorized transfer of the NFT after returning the transfer rights.

Summary

Compared to ERC-4907, ERC-6147 has been optimized in terms of compatibility:

1. Broader applicability: ERC-6147 does not require projects to actively support leasing functions, only the acknowledgment of the owner role is needed.

2. Introduce the concepts of "manageable SBT" and "effective SBT" to provide a more flexible management solution for SBT.

ERC-6147 provides more possibilities for the application scenarios of NFT and SBT, and is expected to promote the further development of the NFT ecosystem.

![Interpreting the latest Final ERC-6147: A minimalist semi-mandatory NFT property separation standard]###https://img-cdn.gateio.im/webp-social/moments-bfff8d0061eaaf89e711e7ade2cf99a6.webp(