The couple teamed up with former Miss Teen USA Kari Ann Peniche for a threesome -- and filmed the tryst.
Gawker's Defamer.com first reported the sex tape by posting an edited version of the video on Monday.
Dane and Gayheart's lawyer Marty Singer insists he will sue anyone who publishes the "private, confidential tape," adding, "From what I've seen, it's a naked tape, not a sex tape."
The footage posted on Defamer.com features the seemingly intoxicated threesome passing a camera around and dreaming up porn names for each other.
Dane states, "My alter-ego name is Peter (and) my dog growing up was called Cocaine, and I lived on Manor Drive, so I'm Cocaine Manor."
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