in march 2001, kazaa was released. its fasttrack network was distributed, though unlike gnutella, it assigned more traffic to 'supernodes' to increase routing efficiency. the network was proprietary and encrypted, and the kazaa team made substantial efforts to keep other clients such as morpheus off of the fasttrack network. in october 2001, the mpaa and the riaa filed a lawsuit against the developers of kazaa, morpheus and grokster that would lead to the us supreme court's "mgm studios, inc. v. grokster, ltd." decision in 2005.