Footnotes, comments, bookmarks, and marginalia on the Web

A W3C Workshop on Annotations

2 April 2014, San Francisco, California

This workshop has already concluded.
To read the summary of the event, or watch the videos, please see the W3C Web Annotations Workshop Report.

Annotating is the act of creating associations between distinct pieces of information. Annotation is a ubiquitous activity online in many guises: comments on articles, footnotes, sticky notes, “hot spots” on images, timestamped notes on video or audio tracks, highlighted text passages in ebook readers, evocative pictures attached to song lyrics, quotes and links on social media, geotagged pinpoints on maps, and even tagged bookmarks, are all forms of annotation. One of the most common and engaging web activities for the average person is discussion of a document or piece of media.

Many projects and companies are now turning to annotations to solve a variety of issues with communication on the web.

W3C recognizes the value and potential in annotations of various types, and is holding a workshop to determine what the web ecosystem needs to fully realize the potential of annotations.

The Challenge

Annotation currently lacks a structured approach. Comments are siloed inside the blog or comment system hosted and controlled by the publisher of the original document, or inside an ebook reader. They aren't readily available for syndication or aggregation, and it's difficult to find more comments by an insightful author if they are scattered around different places on the web. Worthwhile commentary is obscured by trolling, spam, or trivial comments. These are challenges both social and technical.

Other problems are purely technical: interchange formats need to be agreed upon; privacy and security of comments need to be preserved; styling highlighted content across element boundaries is tricky; and finally, anchoring a passage when you don't control the original document, or when it has a multipage or single page view, or when it has newer versions or has otherwise changed from when the annotation was made, is a hard problem, and lies at the heart of annotations.

These requirements should be met across document types, reading systems, JavaScript libraries, and disciplines of study or entertainment. This workshop will focus primarily on the technical issues, with an emphasis on pragmatic solutions.

We want to identify the biggest challenges, most compelling use cases, and most promising solutions for standardization. We invite you to submit a paper and to attend this workshop to help shape the next steps.

Further steps

In February, W3C started a discussion with the community on the development of a charter for a possible Working Group on Annotation at W3C. We anticipate getting further community perspectives on the scope of this proposed charter at this workshop. The plan may then be to revise and finalize that charter soon after this workshop; that charter may then be sent to W3C members for final approval and a Working Group could be started soon thereafter.

Workshop topics

Possible topics include, but are not limited to the following:

Who Should Attend

How to Participate

If you are working on annotations, we want you to attend this workshop. If you want to work on annotations, we want you to attend this workshop.

We want to know more about your state-of-the-art approaches.

The Call for Papers is closed, but registration is still open until 27 March. Registration is free. Register now!

Event Archive Policy: Video and Transcripts

For posterity and for those unable to attend this workshop, we will be recording the video and audio of the event, and will provide a live IRC transcript of the presentations and group discussion. Participants will be asked to sign a media waiver.


W3C's Annotation Workshop is collocated with I Annotate 2014, an industry summit on annotation, which begins the day after W3C's workshop and includes 2 hackdays on the weekend. Attendees of the W3C Annotation Workshop are encouraged to attend the I Annotate summit, as well. I Annotate is organized by the host of the W3C Annotation Workshop, Hypothes.is. Organizations interested in becoming sponsors are encouraged to contact the organizers.


Golden Gate Room

Fort Mason Center

2 Marina Blvd

San Francisco, CA 94123

United States

+1 (415) 345-7500

Wednesday, 2 April 2014



W3C has not negotiated special prices with any hotels, but we have identified 3 reasonably-priced hotels within walking distance of the venue:

Attendees may also wish to check local bed-and-breakfast options nearby.


The nearest airport is the San Francisco International Airport (SFO).

Map to venue


Program Committee




The workshop will focus around several topics identified by the position papers. Each topic session starts with 1–3 five-minute lightning talks, followed by 30–45 minutes of discussion. The goal of the discussion is not be to resolve the technical issues of the topic, but to determine its relevance and priority to standardization. The workshop day will end with a session on establishing the planned deliverables of a proposed Web Annotations Working Group charter.

8:00–8:30 Registration
8:30–9:00 “Opening remarks & Keynote.” Ivan Herman and Doug Schepers, W3C.(Slides, Video)
9:00–9:45 Existing Annotation Systems & Implementation Issues
  • “Hypermedia Notebooks and User Centered Publishing.” Randall Leeds, Hypothes.is, USA. (Submission, Slides, Video)
  • “Microsoft Position Paper.” Chris Gallello, Microsoft, USA. (Submission, Slides, Video)
  • “Supporting Web-based scholarly annotation.” Anna Gerber, University of Queensland, Australia. (Submission, Slides, Video)
  • “Sharing and Contributing Annotations.” Sean Boisen, Logos Bible Software, USA. (Submission, Slides, Video)
9:45–10:00 Break
10:00–10:45 General Requirements on Annotation Models and Systems
  • “Annotation on the Web.” Nick Stenning, Open Knowledge Foundation, UK. (Submission, Slides, Video)
  • “Wiley Position Paper.” James Williamson, John Wiley & Sons, USA. (Submission, Slides, Video)
  • “Position Paper for Annotation Workshop.” Frederick Hirsch and Vlad Stirbu, Nokia, Finland/USA. (Submission, Slides, Video)
  • Requirement Discussion (Video)
10:45–11:30 Robust Anchoring
  • “Position Statement.” Timothy Cole and Thomas Habing, University of Illinois at Urbana-Champaign, USA. (Submission, Slides, Video)
  • “Soleb Position Paper.” Éric Aubourg, Éditions Soleb, France. (Submission, Slides, Video)
  • “Point of View on Annotations in Reading Systems.” Fred Chasen, UC Berkeley & EPUB.js, USA. (Submission, Slides, Video)
  • “Robust Anchoring.” Kristof Csillag, Hypothes.is, USA. (Submission, Slides, Video)
  • Robust Anchoring Discussion (Video)
11:30–13:00 Break, Lunch; Birds of a Feather topic tables
13:00–13:45 Data Annotation
  • “Sharing Knowledge about climate data using Open Annotation: the CHARMe project.” Raquel Alegre, University of Reading, UK. (Submission, Slides, Video)
  • “Better Image Area Annotations.” Robert Casties, Max Planck Institute, Germany. (Submission, Slides, Video)
  • Data Annotation Discussion (Video)
13:45–14:30 Storage and APIs
  • “Hydra for Web Annotations.” Gregg Kellogg, USA. (Submission, Slides, Video)
  • “Evaluating the Experience API (xAPI) for Annotation.” Jason Haag and Tyde Richards, IEEE Learning Technology Standards Committee, USA. (Submission, Slides, Video)
  • “Open Annotation Architecture and Scope.” Jake Hartnell, UC Berkeley & EPUB.js, USA. (Submission, Slides, Video)
14:30–15:00 Break
15:00–15:45 Accessibility & legal issues
  • “Annotation as a Tool for Accessibility for Blind and Vision Impaired Students.” Gerardo Capiel, Benetech, USA. (Submission, Slides, Video)
  • “Could semantic web and accessibility be BFF (best friends for ever) in image annotation?” Mireia Ribera and Bruno Splendiani, University of Barcelona, Spain. (Submission)
  • “Licensing Annotations.” Puneet Kishor, Creative Commons, USA. (Submission, Video)
15:45–16:30 Charter discussion (Video)
16:30-17:00 Break
17:00–17:30 Closing statements (Video)
18:30–21:00 Evening event (hosted by Hypothes.is)

Technical discussion will continue the next two days at the I Annotate summit (register separately).



Hypothes.is is a non-profit organization dedicated to the open annotation of all human knowledge. They are part of a community working towards an open source framework to allow fine-grained critique and community peer review of journal articles, books, news, religious texts, government documents, legislation and the web writ large. Their goal is to create shared infrastructure to help humans reason more effectively together.


Becoming a Sponsor

W3C Workshops, meetups, and other events bring you into direct contact with leading Web technology experts: representatives from industry, research, government, and the developer community.

Whether your interests are focused on a particular topic being discussed by a Working Group, or you wish to reach a diverse international audience setting W3C's strategic direction, sponsorship helps your organization reach W3C's engaged participants.

Sponsorships offset a portion of our meeting costs, so W3C welcomes multiple sponsors for each event. All proposals for sponsorship are subject to W3C approval.

If you're interested in being a sponsor of the Annotation Workshop, please contact J. Alan Bird at abird@w3.org or +1 617 253 7823.

For additional information, please visit the Sponsorship program.