Peer-to-Peer Systems, LLC has filed a lawsuit against Palm Inc. that alleges that the handheld maker infringes on its patent for wireless gaming.
U.S. Patent No. 5,618,045 is for "An interactive multiple player game system including at least two playing devices communicating over an ad-hoc, wireless, all-to-all broadcast network."
This appears to only cover a set-up in which the two devices are directly connected to each other with some wireless standard, like two handhelds playing a game via infrared. The patent does not seem to cover games that are played over the Internet.
Reportedly, Palm and Peer-to-Peer Systems have been in negotiations for a licensing fee but these have broken down. The company is also suing the makers of the Cybiko wireless handheld, which also allows ad-hoc gaming.
Thanks to Pocket Gamer for the tip.