On January 12, 1999, Microsoft Corp. (microsoft.com) was granted U.S. Patent #5,860,073. This particular patent, titled “Style sheets for publishing system(s),” covers “the use of style sheets in an electronic publishing system.” Sound familiar?

The inventors listed in this patent claim to have developed a system whereby “text, or other media such as graphics, is poured into the display region,” at which time style sheetsdefined as “a collection of formatting information, such as fonts and tabs”are applied. This patent seems to overlap concepts laid out in the W3C’s specifications for CSS and the Extensible Stylesheet Language (XSL), which have been in development since at least 1994.

A brief analysis of the patent shows that it has two major flaws, which the W3C and the Web Standards Project (webstandards.org) have already been quick to point out:

• “The existence of prior art,” referring to the fact that style sheets were proposed with the first Web browsers coming out of CERN laboratories in 1994. In fact, style sheets have been around since the 1960s, when they were used for print publications. At best, Microsoft is a Johnny-come-lately to the concept.
• The W3C’s own licensing ensures that the standards developed under its banner are universally available and royalty-free. Because the W3C first developed the concept of style sheets, its license should hold precedence.

Microsoft had representatives on the committees that created these standards, and its own patent refers to documents produced by the W3C regarding CSS, so it seems highly improbable that this patent would stand up to much scrutiny.

George Olsen of the Web Standards Project questions whether the patent should have been granted in the first place, “because [there] are a number of prior examples of similar technology, including the original proposal for CSS,” he says. Also, it is assumed that any organizationMicrosoft includedwith representatives in the W3C will detail any current or pending patents that might affect the W3C standards under consideration, which this patent certainly did. Yet the W3C first heard of the patent on February 4, 1999, when information about the patent was made publicly available. For its part, the W3C presents the claim on its Web site, but attempts to stay neutral as to its validity (w3.org/Style/CSS/Disclosures)

So what does this mean to you? Probably not much. The W3C has published CSS as an open standard, and the genie is already out of the bottle.

Quotation from “Visual Quickstart Guide CSS, DHTML, and Ajax, Fourth Edition Book”