A US appeal court has delivered a mixed ruling in a patent dispute between Research in Motion (RIM) and NTP.
It upheld a decision that RIM had infringed on patents held by NTP, but cancelled an injunction ordered by a lower court and sent the case back for further deliberations.
NTP owns patents for a wireless communications system that it believes covers e-mail systems such as RIM's BlackBerry.
In 2002 a jury in a US district court agreed and awarded NTP U$23.7m (£1.18m) in damages.
The court later issued an injunction preventing sales of the popular BlackBerry wireless e-mail device and server software in the US, but it was stayed pending this appeal.
The Court of Appeals for the Federal Circuit has now ruled that a lower court correctly interpreted several infringement claims made by NTP against the BlackBerry device and software. But it also ruled that the lower court incorrectly interpreted the scope of one key claim.
It said that since a different ruling on that particular claim might change the outcome of the case, it remanded the case to the lower court to decide if the jury verdict should be overturned and the injunction lifted.
Despite this ruling, NTP is pleased with the appeals court decision because the claims that were upheld cover all RIM's products, said company attorney Jim Wallace. NTP believes the lower court will not change the damage award or the injunction, he said.
Trading on RIM's stock was halted pending the release of the decision.
The stock price rose almost $9 from its opening price on the Nasdaq market following the release of the decision, but fell back after investors realized the full scope of the decision.
Trad in the company's shares was halted for about an hour and a half, and when it was resumed, RIM's stock price fell precipitously to close at $85.44, a drop of 5% from its opening price on Tuesday.
Tom Krazit writes for IDG News Service