PDF/E is a subset of PDF 1.6 specifically designed for engineering drawings. It qualifies as an Open Standard and has been approved as ISO 19005-1:2005. PDF/A is a subset of PDF 1.4 specifically designed for archiving purposes. All of its currently ISO approved variants qualify as Open Standards and are published under ISO 15930: It primarily serves as a colour-reliable document exchange format for the printing press. The PDF/X standard, originally based on PDF 1.2 and since revised several times, was developed by the American National Standards Institute's (ANSI) Committee for Graphic Arts Technologies Standards. The extensions are not part of ISO-32000 but may be proposed in the next revision of the format. See below for more information on the patent claims concerning PDF. It should be noted that although Adobe Systems allows royalty-free use of PDF 1.7, other companies hold patents that may or may not encumber the standard. PDF 1.7 is an Open Standard, approved as ISO 32000-1:2008. See below for more information on the different subsets of PDF.

However, several Open Standards were based on subsets of these versions and have been approved by ISO. While specifications were available, Adobes own versions of PDF were never submitted to ISO or recognised as Open Standards. Main versions of PDF PDF versions prior to 1.7 Below follows a list of PDF versions and their status as an Open Standard. Standards based on subsets of the PDF specifications have also been published. PDF was created by Adobe Systems in 1993 and has been published in several versions since then.

Pdf x reader