OpenSea: Operator Filter applies to all NFT series that enforce royalties on the chain. According to news on February 21, the NFT trading market OpenSea further explained the new policy: "Operator Filter (optional tool for on-chain royalty enforcement) applies to new and For existing NFT series that enforce royalties on the chain, for NFT series that do not enforce royalties on the chain, creator income will be optional, with a minimum standard of 0.5%."