At the moment, the ownership of the Secure Macro in Server is based on the user that is adding the macro to the page. After it is added, only the Owner or System Admin can make changes to the Macro.
It is not possible to transfer ownership to another user. This feature is also available in Cloud.
Hence, it will be great if the Server version has the same feature as in Cloud to make shared ownership available for Server
Hosting platform | Server |