The patent, which was originally applied for in 1997, relates to a method of navigating between hyperlinks on a web page by means of a keyboard.
Basically, the patent covers the process whereby a user presses on the tab key of his computer, and is automatically taken to the first hyperlink on an on-screen web page, around which, according to the patent summary, "a focus shape is drawn around the text or graphics for the hot region of the hyperlink".
Another press on the key will take the user to the next hyperlink, and so on.
The user may also tab to an image placeholder, says the summary, "in order to make a decision whether the image should be downloaded or not."
Since tabbing is a standard feature of most web browsers, including Explorer, Netscape, Mozilla and Opera, there has been concern over what use Microsoft will make of the patent.
Speaking to internetnews.com, a Microsoft spokesman 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."
The World Wide Web Consortium's web accessibility guidelines – published in 1999 – expect a user to be able to use his or her tab key to navigate. The guidelines tell site designers to create "a logical tab order through links" to ensure a site will be compatible with this functionality.