Microsoft has been granted a patent from the U.S. Patent and Trademark Office on a process known as tabbing through a Web page in order to find links.
Although the patent award has raised the ire of some in the open source browser community, the implications for the widely used technique are unclear.
The patent (number 6,785,865) is officially titled “Discoverability and navigation of hyperlinks via tabs.”
Microsoft filed for the patent in March of 1997. It covers the process of shifting between links on a Web page using the computer’s tab button.
According to the U.S. Patent office, a “user may discover and navigate among hyperlinks through the use of a keyboard. For example, a user may press a tab key to discover and navigate to a first hyperlink that is part of a hypertext document.”
The abstract also said a user may also tab to a link that is actually a placeholder for an image “in order to make a decision whether the image should be downloaded or not.”
Virtually all modern Web browsers, including Microsoft’s own Internet Explorer and alternative browsers like KDE’s Konqueror, Apple’s Safari, Netscape, Mozilla Firefox, Opera and the console browser Lynx, allow for tabbing between links on a page.
Patent attorney Dan Ravicher, founder and executive director of the Public Patent Foundation (a New York-based non-profit dedicated to busting overly broad patents), said his first question would be whether the patent is valid. “Just because the patent office granted the patent doesn’t mean it’s valid,” he said.
“There are lots of reasons why a patent can be invalid, some of them are prior art. Some of them are other issues. The process of actually getting the patent into court is actually really hard. Only about 1 percent of patents end up in court,” said Ravicher, who also authored an Open Source Risk Management (OSRM) report last month that found Linux to have 283 non-court validated patent infringements.
Ravicher said the only way to prove the validity of a patent is to test it in court, which can be a difficult task. “Only the patent owner can sue you as a way to get the patent in court. There is an exception that says if the patent owner has threatened to sue you, you can take that to court, but if the patent owner doesn’t threaten to sue you, you can’t get the patent into court,” said Ravicher, who is also senior counsel to the Free Software Foundation.
In response to a query from internetnews.com about how it planned to handle the patent, Microsoft said: “We respond to inquiries about our portfolio and typically have private collaborative discussions with companies about using our technology.
Consistent with practice throughout our industry, we don’t believe it’s constructive to identify specific products and start labelling them as infringing or non-infringing.”
One of the many open source browser projects that has tabbing between links is KDE’s Konqueror browser, which is also the basis of Apple’s Safari browser. According to KDE core developer Aaron Seigo, the issue highlights the overall danger of software patents. He noted that Konqueror could work without tabbing between links, though it could impact accessibility.
“This is a very obvious idea, one that follows quite naturally and by necessity for accessibility from our current desktop paradigms,” said Seigo.
The Lynx browser is one of the oldest browsers (still updated regularly though) and is a non-GUI text browser. As such, it relies on tabbing between text links to navigate.
“How are they supposed to enforce this patent? I mean, what impact would it have?” said Rado Smiljanic, a Lynx user and community member. “Would anyone using ‘tabbing’ have to pay Microsoft license fees?”
