how to dispute a registered copyright
The proper method for how to dispute a registered copyright is to use a Copyright Dispute Lawyer. The lawyer would be able to go through the proper channels and tell you what all you need to dispute the copyright.
In order to dispute a registered copyright, you must complete and submit a 'Lodgement of Dispute' form to the relevant organization, clearly defining the material that has been copyrighted. Look here for more information: http://copyrightregistry.com.au/index.php/site/view.main/page=dispute_policy.