Content Center Vault folder permissions - Allow add but not modify?

[G60Dub]

I have a permissions issue with authored custom content.  The libraries themselves are set read only in the project but it appears that end users are able to increment versions of these items within Vault.

Is there a combination of permissions that can be used to allow users to add files to the Content Center/en-US folder in Vault but are then restricted from making further changes - eg permit a user to add files but subsequently not modify them?

[ihayesjr]

You can put the Content Center files in a lifecycle state where they are locked after they are checked in.

Do not put permissions at the folder level.