This is an addon module for EditableSign plugin.

When this addon is installed and enabled, the sign will remember who placed it (without relying on an external data storage such as flat files, or a database), and only the owner of the sign can edit.

Place ES-OwnershipCheck-x.x.x.jar file in plugins/EditableSign/addons folder.
Once you restart the server, EditableSign plugin will automatically integrate this addon into itself and auto-generates a default config file OwnershipCheck_config.yml.