Barracuda Networks plans to defend the popular open-source ClamAV antivirus program from patent threats made by Trend Micro. The issue at hand is Trend Micro’s U.S. Patent 5,623,600 — this covers the concept of server-based AV software on FTP and SMTP gateways, which the company says ClamAV violates.

Excerpt from Ars Technica:

Trend Micro alleges that Barracuda’s inclusion of the open-source ClamAV server-based antivirus software in commercial network security appliances constitutes patent infringement. Trend Micro has already wielded this patent against Symantec, McAfee, and a number of smaller companies, who have settled out of court despite issuing public statements denying that the patent is valid.

The easiest course of action would be to negotiate a licensing agreement with Trend Micro. However, in what it says is an effort to protect the ClamAV project and its users from predatory infringement claims, Barracuda has decided to take the matter to court rather than try to settle it.

In a statement, Barracuda CEO Dean Drako said, “Trend Micro’s actions illustrate that ClamAV and other open-source projects remain vulnerable to commercial patent holders attempting to unjustly hinder the free- and open-source community.”

Of course, Barracuda’s actions are not purely selfless, and they come only on the heels of repeated calls from Trend Micro to either pay up or to stop using ClamAV in its products.

You can read the press release from Barracuda here.