Neo has finalized its NFT royalty standard, assigned as NEP-24. The standard describes an extension of NEP-11 NFT smart contracts that allows them to release royalties to be honored upon resale of the asset.
The standard describes the implementation of a new method, royaltyInfo, that NFT contracts can add and use to specify single or multiple royalty recipients. Royalty amounts are specified per recipient and can be dynamically calculated by a marketplace depending on the sales price.
This mechanism ensures that different NFT marketplaces can agree on the correct payout figures. Additionally, supporting the standard requires marketplaces to broadcast a new event, RoyaltiesTransferred, once for each payout recipient.
Two implementation examples have been provided as part of the standard. The first comes from a Python NFT template from GhostMarket, an early adopter of the standard, and the second has been added as a new C# NFT contract example in the neo-devpack dotnet.
Developers can read more about the standard and how to integrate it with their own projects via the link below:
https://github.com/neo-project/proposals/blob/master/nep-24.mediawiki