Network Associates has been granted a broad US patent for technology covering "various computer program products, systems and methods" for filtering unwanted e-mail messages.
The patent encompasses use of multiple spam-filtering techniques such as compound filters and paragraph hashing. These techniques have been proposed and used by a number of antispam technology proponents, and it was unclear from the filing how the patent would affect competitors to NAI's McAfee antispam offerings.
NAI is just the latest industry player to tout a broad antispam patent. Late last year, e-mail security firm Postini was awarded a US 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 company Symantec paid $62.5m last year to acquire a patent that covers computer hardware or software that scans data in transit between two "mediums".
Researcher IDC predicted that the antivirus software market is set for a compound annual growth rate (CAGR) of 15% through 2007 to $4.4bn, and that messaging security will increase at a CAGR of more than 35% through 2007 to $1.1bn.
Scarlet Pruitt writes for IDG News Service