No abstract available.

In this paper we describe the current approach to using MathML within Tagged PDF to enhance the accessibility of mathematical (STEM) documents. While MathML is specified by the PDF 2.0 specification as a standard namespace for PDF Structure Elements, the interaction of MathML, which is defined as an XME vocabulary, and PDF Structure Elements (which are not defined as XME) is left unspecified by the PDF standard. This has necessitated the development of formalizations to interpret and validate PDF Structure Trees as XME, which are also introduced in this paper.

In this application note we outline the goals of the "LATEX Tagged PDF" project, describe its current status, show how it can already now been used to create accessible and reusable PDFs, and outline our future plans for a successful completion. Further information can be found at https://latex3.github.io/tagging-project/.