New Zealand anti-spam company Death2Spam (New Zealand) Ltd. isn't overly concerned about the U.S. patent granted to competing security vendor Network Associates Inc. last week.
According to news reports, the U.S. patent is broad and covers the use of multiple spam-filtering techniques. These include the use of compound filters and paragraph hashing as well as Bayesian probability rules.
Many of these techniques are used in commercial and open source anti-spam solutions such as Spam Assassin, and have been for a while now, says Richard Jowsey, executive director of Death2Spam.
This "prior art" would make it hard for NAI to enforce its patent.
"The layered defense concept is nothing new," said Jowsey. "Everyone uses it, as it's the only way to catch the multiple vectors used by spammers and virus writers." Jowsey suspects NAI's patent application is little more than an attempt to bolster its intellectual property coffer before going public.
"Patents are legal devices from the industrial age and cannot keep up with the fast pace of the software industry," Jowsey says. "In two years' time NAI's patent will be worthless."
By that time, spammers are expected to have evolved their technologies sufficiently to make existing antispam counter measures obsolete.
"Virus writers and spammers are converging," Jowsey says, and spoke of the necessity to develop broad-based probability analysis systems that look at samples of data to pre-empt new malware. Jowsey envisages a system whereby probability analysis engines "train" traditional signature-based anti-malware.
Jowsey said that his company had considered filing software patent applications, but been advised by lawyers that enforcing those could entail spending up to five years in court, spending large amounts of money without having a certain outcome.