Privacy Interest Group Charter

The mission of W3C's Privacy Interest Group (PING) is to improve privacy on the Web by advising groups developing standards on how to avoid and mitigate privacy issues with their technologies and by incubating new work that reduces privacy risks and fingerprinting surface area. PING also suggests changes to existing standards and technologies to improve the privacy of existing systems. Finally, PING makes recommendations to the W3C Advisory Committee and the W3C TAG about whether a proposed standard would be beneficial or harmful for privacy on the web.

Join the Privacy Interest Group.

Start date 1 October 2019
End date 29 February 2024
Confidentiality Proceedings are public
Chairs Christine Runnegar, W3C Invited Expert
Peter Snyder, Brave
Nick Doty, Center for Democracy & Technology
Team Contact
(FTE %: 0.05)
Philippe Le Hegaret
Usual Meeting Schedule Teleconferences: typically 1-2 per month
Face-to-face: Once annually


The Privacy Interest Group (PING) develops and documents guidelines, patterns, processes and best practices for addressing privacy considerations in Web standards.

PING provides "horizontal review" - offering groups developing web standards on-request guidance on privacy issues and mitigations specific to their technologies. PING aims to offer this review as early in the technology development lifecycle as requested, observing that early feedback is often more helpful. PING may also seek out technologies that might benefit from earlier privacy review and conduct such reviews on its own initiative.

PING incubates standards work on privacy issues by collecting requirements, prototyping, and/or initiating the work within the IG and recommending that the W3C move the work into other groups when appropriate. For example, PING may incubate work to reconcile differences in browser vendors' approaches to privacy-protecting features, potentially to include guidelines, best practices, and standards work.

PING may recommend mitigations for privacy issues found in existing features of the Web platform, up to and including deprecation of the features.

PING may provide input to the W3C Process Community Group on process changes that will improve privacy in Web standards, e.g. by establishing particular requirements on the identification and mitigation of privacy issues in W3C Recommendations.

PING may make recommendations to the W3C Advisory Committee and the W3C TAG regarding the privacy impact of proposed standards.

Success Criteria


In conjunction with W3C's Technical Architecture Group (TAG) PING maintains a Self-Review Questionnaire for Security and Privacy.

PING maintains a document providing further detail on Mitigating Browser Fingerprinting in Web Specifications.

PING is developing and will maintain A Target Privacy Threat Model for the Web to assist developers and implementers to assess the privacy risks of their features.

PING may publish other documents consistent with the above scope such as analyses of privacy issues, prototype specifications, and guidelines for user interface design and future standards.

Dependencies and Liaisons

W3C Groups

It is expected that most Working and Interest Groups will ask PING to review their specifications.

PING will seek horizontal review of its own deliverables for accessibility, internationalization, performance, and security with the relevant Working and Interest Groups and with the TAG.

PING should collaborate with the WICG and TAG to coordinate privacy review of specifications early in their development lifecycle.

PING may collaborate with the W3C Web Advertising Business Group and the WICG on privacy issues related to advertising.


Participation in PING is open to the public. Participants who do not represent a W3C Member should join as Invited Experts. Invited Experts in this group are not granted access to Member-only information.

Anyone may subscribe to the group's public mailing list and engage in discussion. Those who intend to contribute to deliverables will be asked to join the group.


This group conducts its work on the public mailing list public-privacy and in periodic teleconferences, typically 1-2 times per month. Additionally, the group meets face to face at TPAC. PING is experimenting with using a free Slack workspace - interesting discussions from Slack will be called out to the mailing list, and decisions will not be finalized based solely on Slack discussions.

Information about the group (deliverables, participants, face-to-face meetings, teleconferences, etc.) is available from the PING home page.

Decision Policy

As explained in the Process Document (section 3.3), this group will seek to make decisions by consensus. When the Chairs put a question and observe dissent, after due consideration of different opinions, the Chairs should record a decision (possibly after a formal vote) and any objections, and move on.

Patent Disclosures

Interest Group participants have an obligation to comply with patent disclosure obligations as set out in Section 6 of the W3C Patent Policy. These obligations apply both to Recommendation-track work incubated in the Interest Group as well as to feedback offered to Working Groups when reviewing their Recommendation-track specifications.

For more information about disclosure obligations for this group, please see the W3C Patent Policy Implementation.

About this Charter

This charter for the Privacy Interest Group has been created according to section 6.2 of the Process Document. In the event of a conflict between this document or the provisions of any charter and the W3C Process, the W3C Process shall take precedence.

Charter History

The following table lists details of all changes from the initial charter, per the W3C Process Document (section 5.2.3):

Charter Period Start Date End Date Changes
Initial Charter 8 September 2011 15 August 2013 Charter announcement
Launch announcement
Charter Extension 18 December 2013 1 December 2014

Tara Whalen's affiliation updated. Team contact time commitment reduced from .15 to .10 FTE. Dependency on Provenance Working Group dropped since group closed.

Charter Extension 3 December 2014 1 December 2016

Chair affiliation updated. Note about liaisons with newly-created groups. Updates to liaisons: include Web Security Interest Group, Web Application Security Working Group and Technical Architecture Group; remove Government Linked Data Working Group (closed).

Charter Extension 1 March 2018 31 December 2018 Team contact updated.
Charter Extension 21 December 2018 30 June 2019 No changes.
Charter Extension 28 June 2019 30 September 2019 Pete Snyder added as chair.
Rechartered 1 October 2019 31 December 2022

Highlighted PING's role in horizontal review. Removed IAB Security and Privacy program liaison, since program closed. Removed list of specific WG liaisons, since PING expects to work with all of them now. Listing TAG, WICG, and Web Advertising BG for liaison. Increased team contact time commitment to .3 FTE. Tara Whalen stepped down as chair, May 2020.

  • 2021-11-18: Nick Doty appointed as the group co-Chair.
  • Charter Extension 1 January 2023 30 June 2023 No changes.
    Charter Extension 3 July 2023 31 October 2023 Team contact udpate: From Sam Weiler, to Philippe Le Hegaret
    Charter Extension 7 November 2023 29 February 2024 No changes.

    Philippe Le Hegaret, W3C