The Electronic Frontier Foundation's Patent Busting Project takes aim at another patent as the EFF and lawyer Rick Mc Leod have joined forces to request a USPTO re-examination (PDF) of an Ideaflood patent on "virtual subdomains." According to the request, the patent in question describes capabilities that had already been implemented in Apache when the patent was filed.

The patent in question was filed in 1999 and approved in 2004. Patent holding company Ideaflood had it for a while, but the patent has now been transferred to a company called Hoshiko. While Ideaflood owned the patent, it threatened sites like LiveJournal unless they coughed up the cash—and all of this over a technology that wasn't particularly complex and wasn't (allegedly) even novel.



Patent busting, EFF style

The Ideaflood patent describes virtual subdomains. The idea here is that it would be impractical for companies with large number of subdomains (blog hosts that offer username.bloghost.com, for instance) to create new DNS records for each subdomain. The solution was to use "virtual" subdomains that put a wildcard in the DNS record. Instead of creating a thousand DNS entries for ann.bloghost.com, bob.bloghost.com, crazycarl.bloghost.com, etc., there would only be a single entry, *.bloghost.com, and it would resolve to a single IP address. The webserver at that IP address would then read the host request (ann.bloghost.com) and parse it so that it pointed to Ann's public HTTP folder residing somewhere on the server (~login/public_html or wherever).

Mc Leod, who wrote the re-examination request, points out that this capability was already being used early in 1998 by Apache's mod_rewrite module, written by Ralf Engelschall. Engelschall's work and other people's comments on it are preserved in developer newsgroups and could be enough to show that this was a commonly-understood technology by one "skilled in the art."

"This illustrates how an open-source project can establish a public record of technology development and thwart invalid patents," said EFF senior staff attorney Jason Schultz. "The public discussions on the Apache and other mailing lists have shown that Ideaflood's patent claims were without merit and that the patent should be revoked before it causes any more damage to innovation on the Internet."

This prior art is the grounds for the re-examination, as Mc Leod argues that the patent describes techniques that were already "integral and configurable features of the single most popular Web server software available, the Apache Web server, httpd," at the time of the filing.

Of the ten top patents targeted by the Patent Busting Project, three have already had re-examination requests (one of those requests, against Test.com's online test-taking patent, has already been granted). A fourth patent, Clear Channel's live concert recording "invention," has already been overturned.