For maximum flexibility, GhostMarket contracts allow for royalties to be specified as an array of objects in the form: {Address, royalties}
. This allows royalties to be divided and distributed to multiple recipients e.g. If the original NFT was the shared creation of 2 artists, they could each receive a share of the royalties with each sale - say 10% royalty each.
GhostMarket trading contracts enforces a maximum combined of 50% royalties per NFT.
On Phantasma anyone can set royalties and GhostMarket contracts will honour them since it's a chain wide feature, nothing particular is required. On Neo N3, any NEP11 contract can add a method designed by GhostMarket, that allows our trading contract to read and honour them.
On EVM blockchains, we currently only support royalties from our own contracts (no third party contract royalties are supported), but this is currently being worked on and we will announce when ready.