World Wide Web Consortium Clears Patent Hurdle for Web Privacy

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Patent analysis confirms Platform for Privacy Preferences (P3P) does not infringe Intermind Patent -- 28 October 1999 -- Removing a major hurdle to the deployment of privacy-enhancing technology on the Web, the World Wide Web Consortium (W3C) released a legal analysis finding that Platform for Privacy Preferences (P3P) technology does not infringe a patent held by the Intermind Corporation. P3P enables Web sites to inform users of their privacy practices and will give users more control over the use of their personal information on the Web. Widespread deployment of P3P-compliant technologies was threatened when the patent holder sought to charge royalties for products or services using the P3P specification, despite the fact that the technology was developed in an open, collaborative process by a number of W3C Members.

"Given the fundamental importance of privacy protection on the Web, and our commitment to open standards, we decided that it was our responsibility to provide the community with a thorough analysis of the relationship between the patent and P3P," said Daniel J. Weitzner, Technology and Society Domain Leader at the World Wide Web Consortium, responsible for P3P development.

The complete analysis is available on the W3C Web site at

The Analysis

The Intermind Patent (U.S Patent No. 5,862,325) claims rights in certain techniques of controlling interactions between clients and servers, especially with respect to the exchange of personal information. Though much of the Internet is based on such technologies, the assertion of proprietary rights in this field had a chilling effect on the Web community's plans for P3P deployment.

W3C retained noted patent attorney Barry Rein, of Pennie & Edmonds, to evaluate the degree to which P3P does or does not infringe the Intermind patent. Mr. Rein and his team, assisted by Joseph Reagle, W3C Policy Analyst instrumental in the development of the P3P specification, concluded that compliance with the P3P standard can be accomplished without infringing Intermind's patent.

The Legal Argument

The legal conclusion that P3P technologies would not infringe the Intermind Patent rests on a comparison of the technologies claimed in the patent against the structure of P3P. The essential technology in Intermind's patent consists of "communications objects" used as "control structures" to direct client-server interactions. These control structures use object-oriented programming techniques to transfer both executable program instructions and associated metadata from client to server. P3P does not infringe the Intermind patent because it specifies no such control structure. The analysis prepared by Mr. Rein and his team finds:

.... P3P does not include the control structure of the '325 patent claims for at least two fundamental reasons: (1) neither the proposal nor the User Preferences file includes data, metadata, and instructions organized using object-oriented programming to encapsulate the data together with the instructions for using it, and (2) neither the proposal nor the User Preferences file provides location transparency or completely specifies a communications relationship. For these reasons, P3P-compliant Web services and user agents do not literally infringe any claim of the '325 patent.

Web Community Support Critical in Patent Analysis

During the course of the review, W3C called on the Web community to contribute information that might assist the attorneys in their work. W3C received over 100 substantial technology contributions from technologists all over the world. W3C would like to thank all who contributed to the effort for their help.

The Importance of P3P

P3P's design keeps users informed of a Web site's privacy practices, and allows users to control what information they choose to disclose to a Web site, as well as how that information may be used. P3P privacy disclosures and requests for information are expressed in the W3C's widely deployed Extensible Markup Language (XML).

P3P technology was created by a consensus process involving representatives from more than a dozen W3C Member organizations, as well as invited privacy experts from around the world.

For the first time in the history of the World Wide Web Consortium, the open technology development process came into conflict with intellectual property claims. "We felt that we owed it to the Web community to clear up the confusion over the Intermind patent," said Weitzner, "but hope not to make this a regular practice."

About the World Wide Web Consortium (W3C)

The W3C was created to lead the Web to its full potential by developing common protocols that promote its evolution and ensure its interoperability. It is an international industry consortium jointly run by the MIT Laboratory for Computer Science (MIT LCS) in the USA, the National Institute for Research in Computer Science and Control (INRIA) in France and Keio University in Japan. Services provided by the Consortium include: a repository of information about the World Wide Web for developers and users, reference code implementations to embody and promote standards, and various prototype and sample applications to demonstrate use of new technology. To date, over 350 organizations are Members of the Consortium.


W3C Contacts

USA, Asia
Janet Daly, <>, +1.617.253.5884
Andrew Lloyd, <>, +44 1 27 367 5100

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