Network Associates (NAI) has been granted a broad U.S. patent for technology covering "various computer program products, systems and methods" for filtering unwanted e-mail messages, it said Tuesday.
The antivirus software company said that U.S. patent no. 6,732,157 encompasses use of multiple spam-filtering techniques such as compound filters, paragraph hashing, and Bayes rules. These techniques have been proposed and used by a number of antispam technology proponents and it was not clear from the filing how the patent would affect competitors to NAI's McAfee antispam offerings.
"To me this looks like a pretty broad patent," said Rob Tosti, partner in the Patent and Intellectual Property Practice Group of Testa, Hurwitz & Thibeault, in Boston.
Tosti said that using Bayes Rules to calculate the probability of a message being spam was an idea that began to gain momentum in mid-2002. And although NAI applied for the patent in December of 2002, the granted patent presumes that the company has a valid claim.
NAI is just the latest industry player to tout a broad antispam patent. Late last year e-mail security firm Postini was awarded a U.S. patent for an e-mail "preprocessing service" which included using antispam methods such as e-mail filtering and virus detection. Some legal experts have expressed doubt that the patent will stand up to challenges given its wide scope.
Antivirus software vendor Symantec has also made a recent patent play. It paid US$62.5 million last year to acquire a patent that covers computer hardware or software that scans data in transit between two 'mediums.'
It's perhaps no surprise that security vendors are staking their claims with the antivirus software market set for a compound annual growth rate (CAGR) of 15 percent through 2007 to $4.4 billion, according to IDC. The researcher also predicts that messaging security will increase at a CAGR of over 35 percent through 2007 to $1.1 billion.
As competition continues to escalate, it remains to be seen how the security rivals will wield their intellectual property claims.