Older Versions of EPUB
The key IDPF standard is EPUB®, the current version is EPUB 3.0.1. This web page contains information about the history of EPUB development and links to older versions of the EPUB Standard.
EPUB 2 was initially standardized in 2007 as a successor format to the Open eBook Publication Structure or "OEB", which was originally developed in 1999. A maintenance release, EPUB 2.0.1, approved in 2010, was the final release in the EPUB 2 branch.
In October, 2011, EPUB 3 superseded EPUB 2 when EPUB 3.0 was approved as a final Recommended Specification. It was superseded in June, 2014 when the current version, EPUB 3.0.1, was approved as a Final Recommended specification.