Originally published in July, 2017, ISO 32000-2 is the first PDF specification developed within the ISO working-group structure. It enhances the "recipe" for PDF in several ways, including clarifications, new and improved features, various deprecations, and much more.
The initial edition of PDF 2.0 was the culmination of nine years of work by a dedicated group of approximately 30 subject-matter experts from around the world. Not a replacement to PDF 1.7, PDF 2.0 is a refinement of the venerable PDF format, originally published and made freely available by Adobe Systems since 1993.
One major difference as compared with previous versions of PDF; since ISO holds the copyright PDF 2.0 is not freely downloadable.
Unlike previous PDF specifications, however, ISO 32000-2 PDF 2.0 is an open standard. Any subject-matter expert who is a member of the PDF Association or whose country is a member of ISO can join other experts and help determine the nature and direction of the world’s de facto electronic document format. This is because the PDF Association has a formal Category A Liaison status with ISO and members may access all ISO documents while in development. A list of PDF-related ISO work is maintained here.
A dated revision of PDF 2.0 is currently being finalized by the subject matter experts in the responsible ISO committee (ISO TC 171 SC 2 WG 8). This revision will soon replace the original 2017 edition as it includes a number of corrections and improvements from early adopters, as described here. This updated Draft International Standard (DIS) of PDF 2.0 is currently available for public review from ISO.
The PDF Association also maintains an archive of reference files, with many originally published by Adobe Systems, that are used as normative references (and thus necessary to complete implementation) in ISO 32000-2. Many of these documents are freely downloadable.