Ask HN: How can you proof that your website content has been plagirized?

Proof, as in 100% proof ? Or prove ? And Plagiarized.

You are going to have to prove 'provenance'.

http://en.wikipedia.org/wiki/Provenance

This is a very complicated subject, the best thing you can do is to document very carefully the process of creation, time stamps and so on, and then to use those to challenge the people that cloned your content.

Mostly in the context of college, but useful stuff anyway:

http://www.bobbyelliott.com/Plagiarism.htm

While that's a difficult question depending on your meaning, you can get some info at http://copyscape.com. I paid for some premium credits personally, allows you to automatically check every page of your website.

Edt: clickable link.

Will Copyscape show which content came first?