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Trend Micro’s attack on open source

Trend Micro are demanding that Barracuda Networks pay licensing fees, alleging that they infringe U.S. Patent No. 5,623,600 with their use of the open-source anti-virus tool ClamAV. Here’s a Barracuda press release, and here’s some details from Barracuda:

Trend Micro alleges that Barracuda Networks and ClamAV infringe on Trend Micro’s U.S. Patent No. 5,623,600. Barracuda Networks believes that the patent is invalid due to prior art and further believes that neither its products nor the ClamAV software infringe the patent.

On Sept. 21, 2006, Trend Micro sent Barracuda Networks a letter regarding a license to Trend Micro’s ‘600 patent. After several discussions on paying a license for the patent, Trend Micro demanded Barracuda Networks either remove ClamAV from its products or pay a patent license fee. Barracuda Networks felt it had no choice other than to file for a declaratory judgment in early 2007 in U.S. Federal Court to invalidate Trend Micro’s ‘600 patent and end continued legal threats against Barracuda Networks for use of the free and open source ClamAV software.

Trend Micro subsequently responded to that declaratory action and more recently, Trend Micro filed a claim with the International Trade Commission (ITC). The ITC voted to investigate the claim in December 2007. Trend Micro’s ITC claim alleges that Barracuda Networks infringes on Trend Micro’s ‘600 patent, but effectively implies that anyone using the free and open source ClamAV software at the gateway infringes the patent.

The interesting aspects of this case, from my point of view, are twofold — the patent is a classic bad software patent, very broad and totally obvious both now and at the time it was issued; and it hinges on Barracuda’s use of the free software antivirus product, ClamAV. Given Apache SpamAssassin‘s prevalence in many anti-spam mail filtering appliances (including Barracuda!), this is a very worrying precedent for us — our product could be next, for some other patent troll company’s extortion scheme.

For what it’s worth, it appears this patent has long been a licensing moneyspinner for Trend. In 1997, once the patent was issued, Trend went on a spree; McAfee, Symantec and Integralis were sued, eventually buying licenses, as did Electric Mail Company. 2 years ago, Fortinet were sued and settled in their case.

I happily gave Barracuda a quote for their press release on this:

“Trend Micro’s actions are clearly an attack on free and open source software and its users, as well as on Barracuda Networks. The ‘600 patent covers a trivial method, one which was obvious to anyone skilled in the art at the time the patent was written, and should be rendered invalid as soon as possible. I hope that Barracuda Networks is successful in its attempts to defend all users from this patent shakedown.”

If you know of prior art for this patent, please head over to Barracuda’s site and provide details — helping to fend off this protection racket would be good for all of us. Barracuda say:

People should look for art dated prior to Trend Micro’s filing date of September 26, 1995. The ‘600 patent is entitled “Virus Detection And Removal Apparatus For Computer Networks.” We are interested in all material, including software, code, publications or papers, patents, communications, other media or Web sites that relate to the technology described prior to the filing date.

In particular, this prior art should show antivirus scanning on a firewall or gateway. However, many of the claims do not require virus detection at a gateway. So any material that illustrates virus scanning on a file server is also of interest.

We also believe that a product called MIMESweeper 1.0 from a company called Clearswift, Authentium, or Integralis anticipates several claims of the ‘600 patent. We have yet to locate a copy of this product and would appreciate anyone who has a copy sending it our way.

Some more coverage:

  • Don Marti at LinuxWorld: ‘Regardless of the decision in this case, software patent trolls will continue to be a problem for all software companies, Eben Moglen says. “Getting them to [not operate] in your neighborhood is the best you can do.”‘

  • Matt Asay at C|Net: ‘Antivirus and antispam innovation has tended to come from open source, not the large proprietary vendors. Trend Micro’s lawsuit is designed to put cash in its pocket but will end up hurting the consumer.’ (Matt led with my quote ;)

  • GrokLaw: ‘Anyone using ClamAV, should Trend Micro be successful, is potentially a target.’

  • Ars Technica: ‘The patent is very clearly without merit, but that hasn’t stopped Trend Micro from using it to threaten ClamAV and extort money from several companies. Situations like this demonstrate a very urgent need for patent reform and illuminate the risks posed by broad software patents, particularly in the area of security.’

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