W3C Working Draft 28 September 2001

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Massimo Marchiori, W3C/MIT/UNIVE (massimo@w3.org)


Lorrie Cranor, AT&T

Marc Langheinrich, ETH Zurich

Massimo Marchiori, W3C/MIT/UNIVE

Martin Presler-Marshall, IBM

Joseph Reagle, W3C/MIT

Copyright ©2001 W3C® (MIT, INRIA, Keio), All Rights Reserved. W3C liability, trademark, document use and software licensing rules apply.


This is the specification of the Platform for Privacy Preferences (P3P). This document, along with its normative references, includes all the specification necessary for the implementation of interoperable P3P applications.

Status of This Document

This section describes the status of this document at the time of its publication. Other documents may supersede this document. The latest status of this document series is maintained at the W3C.

This is the 28 September 2001 Last Call Working Draft of the Platform for Privacy Preferences 1.0 (P3P1.0) Specification, for review by W3C members and other interested parties. This Draft has been produced by the P3P Specification Working Group [member only] as part of the P3P Activity. The 24 September Last Call Draft was republished to include a missing change already approved by the Working Group (an embedded DATASCHEMA is now child of POLICIES rather than of POLICY).

The current draft is a revision of the 15 December 2000 Candidate Recommendation Draft. Due to substantive changes based on feedback from implementers, the Working Group has agreed [members only] to return this draft to Last Call to invite comments and input from W3C Members and the community at large. A change log with a summary of the modifications occurred from the 15 December 2000 Candidate Recommendation is included at the end of this document for convenience. Because these changes are based on solid implementation experience, the P3P Specification Group maintains all the Candidate Recommendation milestones and expects to request Proposed Recommendation after all those milestones and comments from this Last Call are properly addressed.

The last call review period ends 15 October 2001. Please send review comments before the review period ends to www-p3p-public-comments@w3.org (publicly archived).

The milestones are:

  1. at least one P3P user agent implementation integrated into an HTTP user agent capable of fetching HTML files that includes all of the functionality required and recommended by this specification

  2. a second P3P user agent implementation of each specified function (these functions may be demonstrated across several partial P3P implementations or they may be demonstrated in a second full P3P implementation)

  3. at least one special-purpose tool for generating P3P policies and policy reference files

  4. at least one tool for converting full P3P policies to compact policies

  5. at least 10 P3P-enabled production web sites

  6. at least one web site that illustrates each of the example scenarios in Section 2.5 of the P3P1.0 specification as well as at least one web site that uses mini-policies (these may be either production web sites or demonstration sites)

Furthermore, before requesting that this specification be advanced to Proposed Recommendation status, the Working Group will:

  1. Prepare a W3C Note describing RDF data models representing P3P policies and policy reference files.

  2. Submit an Internet Draft to the IETF describing the P3P header and request that an RFC be issued documenting this header.

  3. Prepare a set of test policies and policy reference files that user agent implementers can use to demonstrate that their implementations behave correctly. This should include examples of policies that contain syntax errors.

  4. Specify the appropriate behavior for user agents upon encountering a policy with invalid syntax.

The working group also encourages implementers to explore the possibility of implementations in web proxies and mobile devices, as well as implementations that can import user preferences using the [APPEL] language.

A list of current public W3C Working Drafts can be found at http://www.w3.org/TR.