The Grokster software contains adware, which lead to the creation of Clean Grokster, a third party version of the software without ads. Grokster aggressively pursued distributors of Clean Grokster, sending out cease-and-desist orders and shutting down websites.
In April 2003, Grokster obtained a ruling by a Los Angeles federal court
judge, Stephen Wilson, in its favour against the RIAA and the motion picture industry which stated that its file swapping software was not illegal. On 20 August 2003, the decision was appealed by Grokster's opponents.