Ticketmaster operates an online ticket agency web site where consumers can purchase tickets to local events throughout the United States. Ticketmaster sells advertising space on the front page of its web site but not the embedded pages. Microsoft put up various city entertainment web sites under the domain name "sidewalk.com." Prior to this suit being filed, the parties attempted to negotiate a linking agreement from Microsoft's "sidewalk" web sites to Ticketmaster's web site which would allow visitors to Microsoft's sidewalk web sites to purchase tickets online through the Ticketmaster web site. Negotiations broke down but Microsoft went forward and included a link to Ticketmaster's embedded ticket purchasing page in its sidewalk web sites. Ticketmaster, meanwhile, signed a linking agreement with "City Search" a sidewalk.com competitor.