Submitted by leastwood
https://github.com/code-423n4/2022-03-joyn/blob/main/core-contracts/contracts/CoreCollection.sol
https://github.com/code-423n4/2022-03-joyn/blob/main/royalty-vault/contracts/RoyaltyVault.sol
The Joyn documentation mentions that Joyn royalty vaults should be equipped to handle revenue generated on a collections primary and secondary sales. Currently, CoreCollection.sol allows the collection owner to receive a fee on each token mint, however, there is no existing implementation which allows the owner of a collection to receive fees on secondary sales.
After discussion with the Joyn team, it appears that this will be gathered from Opensea which does not have an on-chain royalty mechanism. As such, each collection will need to be added manually on Opensea, introducing further centralisation risk. It is also possible for users to avoid paying the secondary fee by using other marketplaces such as Foundation.
Consider implementing the necessary functionality to allow for the collection of fees through an on-chain mechanism. ERC2981 outlines the appropriate behaviour for this.
sofianeOuafir (Joyn) confirmed and commented:
