A collaborative effort needs to be applied to ensure all contest entries are original. Contest holders and designers may do these things if they want to check an entry's authenticity or suspect one to be copied:
Read comments from other freelancers identifying any copyrighted material on the Public Clarification Board.
Ask freelancers about their submission and whether any photos, fonts or clipart were used. Contest holders can make use of the Private Message Board while designers can comment on entries.
Use image search sites such as TinEye.
We encourage everyone to report entries that are copied from another design or using unlicensed stock imagery, copyrighted material, explicit content or advertising. Follow the steps on how to report an entry in this article: How to Report a Contest Entry