NFT royalties are enforced on blockchain platforms through smart contracts, which are self-executing codes embedded into the NFT's metadata. These contracts automatically trigger royalty payments whenever an NFT is resold on a marketplace that supports royalties. The smart contract specifies the percentage of each sale that will be sent to the original creator, ensuring that they receive ongoing compensation from secondary market transactions.

When an NFT is sold, the smart contract automatically allocates the predetermined royalty amount to the creator’s wallet before transferring the remaining funds to the seller. This process is transparent and immutable, meaning that once the royalty terms are set, they cannot be changed unless the NFT itself is reissued under new terms.

However, royalty enforcement is limited to marketplaces that support this feature. Some decentralized or peer-to-peer platforms may not honor royalty agreements, which poses a challenge for creators relying on consistent income from resales. Therefore, creators often prefer to mint and list NFTs on marketplaces like OpenSea or Rarible, which support automatic royalty payments.

Overall, blockchain’s decentralized nature and smart contracts enable a streamlined and reliable mechanism for ensuring creators receive ongoing royalties, though gaps in platform compliance can create inconsistencies.