The popular BlackBerry wireless e-mail device does not infringe upon patents held by NTP for a wireless communications system, claimed lawyers for Research in Motion.
The appeal, if granted, would allow RIM to continue selling the BlackBerry device and avoid paying NTP $54m in damages. In 2002, a jury found that RIM willingly infringed upon patents held by NTP.
RIM's appeal centres around what it claims were procedural errors by the district court handling the case, including the misinterpretation of NTP's patents and the relevance of US patents to a system partially contained in Canada.
Tom Campana developed a wireless communications system for his pager company that he later patented, and the BlackBerry infringes upon that patent, said James Wallace, an attorney representing NTP.
NTP was incorporated to hold Campana's patents, and does not make any products or provide any services, he added.
RIM's lawyers argued that Campana's wireless communications systems only allowed users to read and print e-mail, while the BlackBerry allows users to reply and forward corporate e-mail on a wireless handheld device, RIM said.
It insisted that the district court improperly interpreted this and other aspects of the patent claims as broader than specified in that patent.
"Under a proper claim construction and statutory interpretation, the accused products and services avoid infringement as a matter of law," RIM argued.
RIM also argued that since the relay - a key component of its wireless e-mail system - resides in Canada, US patent law does not apply.
NTP asked the appeals court to uphold the lower court's ruling and enforce the injunction imposed by the lower court, Wallace said.
The decision to grant the appeal could take up to two months, he added.
Tom Krazit writes for IDG News Service