In Metro-Goldwyn-Meyer Studios V

In Metro-Goldwyn-Meyer Studios v.Grokster,Ltd.,Grokster claimed a fair use exception to the copyright infringement claim because their process was such that it was impossible for Grokster to know if the users of their device were infringing or not:

A) the Supreme Court agreed that since Grokster could not have known whether infringement was occurring or not, that Grokster could not have been held liable either directly, indirectly or vicariously.
B) the device provided by Grokster to its customers was capable of substantial non-infringing uses so the fair use exception articulated in the Sony case was met.
C) Grokster was denied the fair use exception because the majority of their business model was dedicated to appealing to former Napster customers and the model showed intent to infringe on copyrights.
D) Grokster was allowed to use the fair use exception because all of the music their device was designed to copy was already in the public domain and therefore not protected