EPUB is widely deployed in book publishing and if the archival version of this is also standardized, it has the potential to become widely used to preserve human knowledge and culture. Work is now underway by ISO to define the archiving standard for EPUB 3 files.

There are many reasons a book publishing organization should care about archiving and long-term preservation:

  • Your authors will want their contributions to be part of our cultural and intellectual heritage, and if used for research also will expect their contributions to be part of the scholarly record. This means the content will need to outlive current formats and even organisations.
  • Long-term preservation should be part of your disaster recovery planning and strategy. This provides your organization with insurance for your valuable content, and a safety net to meet an array of commercial obligations.
  • You need to be able to manage your content well and hand it over in good form between parts of your organization. Good content management practices facilitate long-term preservation.
  • Your customers want this, particularly if you publish books used in universities. Long-term digital preservation is a standard requirement in license agreements between publishers/ and university libraries.
  • More standardised approaches to digital preservation can decrease cost, whether you are delivering content to a chosen archiving partner or to a national library to meet legal deposit obligations.

Work is now underway by ISO to define the archiving standard for EPUB 3 files. The terms of reference for this work are to:

  • Agree which EPUB features are required for long-term preservation and features which should be avoided if possible.
  • Specify metadata elements which are required or recommended for long-term migration and preservation.

EPUB 3 is generally regarded as a suitable format for digital archiving because it is an international standard, the format is open and well-documented, new releases are generally forward/backward compatible, it offers a degree of protection against file corruption, it is well maintained and regularly updated, and it is generally interoperable.


Dr Alicia Wise (Executive Director, CLOCKSS Archive, which is a not-for-profit long term preservation service jointly owned and governed by publishers and libraries) contributed this piece and will be chairing the EPUB/a work for ISO, representing NISO and ANSI. To stay informed about this work, or to get involved, please email her at awise@clockss.org.