Originally Posted by HarryT
Dear me, is that old chestnut really floating around still?
. Believe me, it has absolutely no legal standing whatsoever. Any amateur magician knows a dozen different way to get things in and out of "sealed envelopes".
I'm from the Philippines, so it "works" here, but as pointed out, it's not undeniable proof, but evidence in helping prove that the work originated from you.