Call for Review - Public Draft of EPUB 3.1

September 6, 2016

On September 6, 2016, the IDPF Board of Directors unanimously approved elevation of EPUB 3.1 to Public Draft status. EPUB 3.1, developed by the EPUB Working Group, represents a new major version of EPUB. Although generally compatible with EPUB 3.0.1, significant changes have been introduced in this new version (e.g., changes in metadata expressions and removal of support for some EPUB-defined features).

Work on EPUB 3.1 began in October of 2015, with a goal of simplifying the format and better aligning with the Open Web Platform. Three informal Editor's Drafts have been published in the last year, the most recent on August 1. These drafts were used to solicit community feedback on the changes the Working Group was seeking to implement. A list of changes that have been made during these review cycles is available in the Changes from 3.0.1 document. The Working Group is now confident in presenting a formal draft to the IDPF membership for review, as well as to any other parties interested in the evolution of the format.

The EPUB 3.1 revision also introduces a new accessibility specification and techniques document. Although developed as part of EPUB 3.1 and to provide guidance on making conforming EPUB publications accessible, these new documents are designed to be equally applicable to older versions of the specification.

The Working Group is seeking input on the feasibility and implementability of these specifications. Comments on the draft specification are solicited through September 27, 2016. Those affiliated with IDPF member organizations are encouraged to join the EPUB email list to participate directly in the development process. Members and non-members can also provide feedback via the IDPF GitHub issue tracker. (Note that new feature requests are no longer being considered for EPUB 3.1, but can be logged for future consideration.)

According to IDPF policies, the next steps in the approval process after Public Draft are for the Board to elevate the (potentially revised based on comments) specification to Proposed Draft for a final member review (including Intellectual Property review), followed by a member vote to approve as a final Recommended Specification.

The draft specifications are available at:

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