Trend Micro is suing Barracuda Networks over its use of the free open source antivirus software, ClamAV. If it wins, open source advocates fear it threatens all users of the free software and will legitimise the use of patent law to attack OSS.
Following months of legal threats issued to Barracuda Networks, Trend Micro is suing its rival over its use of ClamAV -- a product maintained by US open source company Sourcefire -- on the grounds that Barracuda Network's use of the software in some of its own products infringes a patent held by Trend Micro on applying AV via gateway proxy servers.
Trend Micro alleges that ClamAV has allowed Barracuda's products to operate in a way that infringes a patent granted to the company in 1997.
"Trend Micro was the first company to extend antivirus protection from the desktop to gateways and servers, and the patent -- co-authored by the company's CEO Eva Chen in 1997 -- reflects and protects these vital technical advances," the company said in a statement in 2005 after the US International Trade Commission ruled against another security company, Fortinet, for infringing on the same patent.
The patent stakes claim to AV software capturing viruses at the gateway through the use of File Transfer Protocol (FTP) and Simple Mail Transfer Protocol (SMTP) proxy servers for Web and e-mail virus filtering respectively.
Since 2006, Barracuda Networks has been receiving threats from Trend Micro's legal team which are aimed at forcing Barracuda to either pay licence fees when using ClamAV or to stop the software in its products, according to Barracuda's CEO and president, Dean Drako.
Drako says that he has tried to contact Trend Micro's legal department, but his attempts have been ignored. He has now asked the open source community for help to undermine Trend Micro's claims.
Richard Stallman, founder of GNU Project and Free Software Foundation, has called Trend Micro a "despicable predator" for its actions.
"This attack is an example of the threat that software patents impose on all software developers: at any moment, you can get sued for using code with the author's permission, or even for the code you wrote," he said in a commentary on Linux.com.
"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," said Drako in a statement.
However Trend Micro's legal team claim that the case is not against open source, but about stopping another company profiting from its intellectual property.
In order to stop the initial legal threats, Barracuda Networks filed for a declaratory judgment with the US Federal Court last year, attempting to invalidate Trend Micro's patent.
"Trend Micro appears to be seeking an interpretation of its ... patent such that it would have exclusive control of gateway antivirus scanning. Scanning for viruses at the gateway is an obvious and common technique that is utilised by most businesses worldwide. So this interpretation would mean that anyone, including the owners of the more than one million active ClamAV installations, could potentially be sued by Trend Micro," Drako said.