Rarible DAO Demos Programmable NFT Royalties Smart Contracts 

Content creators and artists will likely be pleased with the news that there is now a solution for maintaining royalties on non-fungible tokens (NFT) even when a piece is sold on secondary markets. Essentially, including a file in the ERC-721 contract and setting parameters enables the defined royalties to be passed on with the NFT.

Source: Rarible DAO Demos Programmable NFT Royalties Smart Contracts – BeInCrypto