From Courthouse News we learn that Teller has filed suit against another magician to protect a copyrighted effects that has been a staple of his act with Penn Jillette since 1976. According to CourthouseNews.com:
Shadows, Penn's name for the act, "is the oldest, most venerated piece of material in continuous use in Penn & Teller's Show, and while other material has come and gone, it has remained as a universal favorite," the lawsuit states. The act involves a spotlight trained on a bud vase containing a rose. The light falls, and a shadow of the real rose is projected onto a white screen behind it. Teller then enters with a large knife and severs the leaves and petals off the rose's shadow while the corresponding leaves on the real rose fall to the ground, "breaking from the stem at exactly the point where Teller cut the shadow projected on the screen behind it," the lawsuit states.
Dutch performer Gerard Dogge, who performs under the name Gerard Bakardy, has been performing the trick that Teller copyrighted in 1983, according to the complaint. Calling his version "Rose & Her Shadow" in a YouTube video, Bakardy allegedly offers to sell the secrets behind the trick for $3,050.