"The original style sheet implementation dates from the mid-70's," said Netscape vice president of client products Jim Hamerly. "At least 20 commercial systems have supported style sheets since that time. We view this patent as largely not an issue."
With style sheets, Web authors can describe how a page is formatted independent of the content. One style sheet can apply to any number of pages.
Last week, Microsoft sent a letter to W3C members in an attempt to allay fears regarding its patent. The February 4 letter is from Microsoft's Thomas Reardon to W3C director Tim Berners-Lee.
"While it is somewhat disconcerting that Microsoft's motivations with the W3C would be questioned, we are more than willing to explain the current situation in the hopes that it will clear the air and result in other companies taking similar patent positions with the community's interest in mind," Reardon wrote.
Reardon pointed out that Microsoft has had other patents on technologies under consideration by the W3C.
"To ensure that the technology that we have submitted will be free from the cloud of potential patent questions...we have typically committed to freely sharing our patent rights, for use in implementing a standard that results from our submission, with other W3C members who are willing to do the same," he wrote.
Reardon cited Microsoft's licensing language that comes attached to its W3C submissions. It reads:
"Microsoft agrees that, upon adoption of this contribution as a W3C recommendation, any W3C member will be able to obtain a license from Microsoft to implement and use the technology described in this contribution for the purposes of supporting the W3C recommendation on a royalty-free basis. One condition of this license shall be the party's agreement to not assert patent rights against Microsoft and other companies for their implementation of the W3C recommendation."
Reardon denied that holding a patent and supporting open standards were mutually exclusive, and defended Microsoft's interest in holding the patent defensively.
"It would be unreasonable to require a company to develop a technology, submit the technology as a standard, give up its own patent rights in the standard submission, but remain exposed to claims of infringement by other companies, who are themselves free to use the technology and patents of the submitting company," Reardon wrote.
The patent, US58 60073, was filed July 17, 1995, and issued January 12, 1999.
The W3C said it had not had a chance to review the patent, and was looking into the matter.