Plagiarism of online material may be proven using the Internet Archive Wayback Machine (archive.org).

Many writers and researchers are reluctant to publish online for fear that their work will be plagiarized and used without attribution elsewhere. For example, junior or freelance researchers may worry that their ideas will be 'stolen' and published under the name of professional or senior researchers; and that then it could be hard to convince people that in fact the idea had originated elsewhere. However, if this happens, plagiarism may be objectively proven by a service called the Internet Archive Wayback Machine (archive.org). Archive.org permits clarification of the issue of dates--and allows the reader to draw their own conclusions about authorship, whether charitable or otherwise. In sum, archive.org is a little known, freely available and potentially very useful mechanism for defending intellectual property rights.