In its lawsuit filed in U.S. District Court in Delaware, Juno alleged that Qualcomm, the maker of Eudora email software, and NetZero, a provider of free Internet access, have infringed on technology that Juno developed. The technology enables advertisements and other content to be displayed while a customer is offline.
In the filing, the New York-based company alleged that NetZero and Qualcomm are "producing, distributing and encouraging" the use of software that "unlawfully" installs Juno's patented technology into the latest version of Qualcomm's Eudora email software.
A representative for NetZero said the company does not comment on legal issues. Qualcomm was not immediately available for comment.
Juno faces increasing competition from rivals such as NetZero, EarthLink and America Online, as ISPs aggressively move to set themselves apart in the market.
"The hottest thing right now is getting a patent on your business model," said Jason Epstein, Internet attorney at Memphis-based law firm Baker Donelson. "At first blush, (this type of suit) strikes against the idea of the free market and competing head-to-head (with rivals), so business method patents are the subject of heated debates right now."
For the most part, Epstein said business patent lawsuits are difficult to prove.
Juno said that in the latest version of Eudora, a setting dubbed "sponsor mode" mirrors its email advertising technology, allowing advertisements to be displayed while people read and write email on or offline.
The company's "242" patent relates to a processing technology that allows its customers to read and write email and to interact with advertisements without being connected to the Web. The advertisements, or other digital information, are downloaded to customers' computers while they are connected to the Web and then are "cached," or stored on their computers, for later display.
The company said it is seeking monetary damages and a permanent injunction prohibiting future infringement of the patent by NetZero and Qualcomm.
Juno, which received the patent Sept. 15, 1998, said it also has been granted the exclusive right to preclude others from using the technology until 2016.