Well a "template" suggests "copy with some changes"... so how does one determine they have the original? If you were successful at registering copyright for it, hire an attorney sue them in court.
If you designed the template, and made it available to the public domain, I would say it is public domain. As fathom said, how do you determine it is the original? or was yours also based on someone's work? If of course it is that important, hire an attorney.