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The PDF/UA Technical Working Group (TWG) drives development of ISO 14289 (PDF/UA) through its association with ISO TC 171 SC 2 WG 9 and publishes resources for developers who need to understand the International Standard for universally accessible PDF.

PDF/UA is of interest to those concerned with conformance to regulations requiring accessible electronic content including WCAG 2.1, Section 508 in the US, Canada’s Common Look and Feel standard, Britain’s BS 8878, and others.

Join us!

The PDF/UA Technical Working Group is a collaboration of PDF software developers and PDF accessibility subject matter experts who use the TWG's resources to share their knowledge and experience in a vendor-neutral space.

Members of the PDF Association are entitled to participate in online and in-person PDF/UA TWG meetings, subscribe to the listserv, access draft documents and gain other benefits as well. Review the options for membership, or get in touch to learn more!

Communicate with us!

There are a variety of ways for both members and non-members to participate in accessibility technology development under the umbrella of the PDF Association. Email to get in touch with the PDF/UA TWG or simply to provide feedback.

History of PDF/UA

  • 2021-04-21 The PDF Association publishes the Matterhorn Protocol 1.1
  • 2020-09-16 The PDF Association publishes version 1.1 of the PDF/UA Reference Suite
  • 2019-06-11 The PDF Association publishes Deriving HTML from PDF, a usage specification for tagged ISO 32000-2 files
  • 2019-06-10 The PDF Association publishes the Tagged PDF Best Practice Guide: Syntax, a guideline for developers implementing tagged PDF and PDF/UA
  • 2018-12-01 The PDF Association creates the PDF Accessibility Liaison Working Group
  • 2016-03-31 ANSI adopts PDF/UA-1 as an American National Standard, technically identical to the ISO standard, but available for only $15
  • 2015-02-18 The US Access Board adopts PDF/UA for its new draft NPRM updating US federal government ICT Standards and Guidelines
  • 2014-12-17 ISO publishes ISO 14289-1:2014, a minor technical update
  • 2014-07-29  AIIM publishes the PDF/UA-1 Technical Implementation Guide for ISO 32000
  • 2014-06-14  The PDF Association publishes the PDF/UA Reference Suite
  • 2014-04-30  The PDF Association publishes the Matterhorn Protocol 1.02
  • 2013-10-03  AIIM updates the PDF/UA Technical Implementation Guide to version 1.2a
  • 2013-08-15  Access for All announces their free PAC 2.0, the first implementation of the Matterhorn Protocol
  • 2013-08-04  The PDF Association publishes the Matterhorn Protocol, the definitive validation algorithm for PDF/UA
  • 2013-03-07  AIIM publishes PDF/UA Technical Implementation Guide: Understanding ISO 14289-1 (PDF/UA-1)
  • 2012-08-16  AIIM publishes Achieving WCAG 2.0 with PDF/UA
  • 2012-08-15  Adobe Systems announces its intention to integrate PDF/UA into their products
  • 2012-08-01  ISO publishes ISO 14289 (PDF/UA)
  • 2004 AIIM Standards launches the PDF/UA committee to study accessibility guidelines for PDF technology

Note: ISO 14289-1:2014 is ISO’s first fully accessible standard; the document conforms to PDF/UA.


Matthew Hardy

Klaas Posselt

Membership has its benefits

PDF Association membership offers many technical benefits to developers and significant marketing value to software publishers.

Learn more, and sign up today!