Unlike some other intellectual property rights, copyright is merely a right to prevent unauthorized copying of an original work. The burden of proof in litigation is on the copyright owner to show that copyright exists in the work in question and that the alleged infringer (directly or indirectly) copied the work. If this chain of copying cannot be shown or does not exist, then there is no infringement. If there has been copyright infringement, then court action may be necessary to stop it continuing, and you may be able to claim financial compensation for any acts of infringement.