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Silktide checks that a PDF carries a valid metadata record, and that it includes the marker declaring the document conforms to the accessibility standard for PDFs. The metadata is where a document states what it is: its title, its language, and any standards it claims to meet.

The record is stored as inside the file. This check reports two problems: a record that is missing or malformed, and a well-formed record that never claims conformance.

Why this matters

The metadata record is where several things a reader depends on are kept, so a missing or broken record takes them all out at once. The title a announces is there, and so is the language it uses to choose a voice. When the record is malformed rather than absent, this is worse than it sounds: software may read part of it, so the document appears to have a title in one program and none in another.

The conformance marker matters for a different reason. It is how a document declares itself accessible, and tools act on the declaration. Some assistive technology treats a document that claims PDF/UA conformance differently from one that does not, and conformance checkers, procurement processes, and compliance reporting all look for the claim rather than inferring it. Without it, a genuinely well-built document gets no credit for being well built: it is indistinguishable from an untested one.

The claim is a statement, so it should only be present when it is true. Asserting conformance in a document that does not meet the standard is worse than asserting nothing, because it tells readers not to expect problems.

How to fix it

  1. Export with PDF/UA output enabled. In LibreOffice, select "Universal Accessibility (PDF/UA)"; in InDesign, use the accessible export preset; in Word, keep "Document structure tags for accessibility" enabled. These write a valid record and the conformance marker together.
  2. Fix the document's real accessibility problems first, then claim conformance. The marker is the last step, not a shortcut.
  3. Or run Silktide remediation, which writes a valid record and adds the conformance claim only when the document has earned it. See How PDF remediation works.
  4. Check the metadata after any tool has touched the file. Compression utilities, redaction tools, page-merging tools, and signing tools all rewrite PDFs, and some of them discard the record.

How Silktide tests this

  1. Find the PDF documents linked from your website, and analyze each unique file once however many pages link to it.
  2. Look for the metadata record and confirm it is well formed.
  3. Look for the PDF/UA identifier within it.
  4. Report the document when the record is missing or malformed, or when the identifier is absent.

Whether the metadata's contents are useful is checked separately: see PDF title for the title and PDF language for the declared language.

Troubleshooting

The document is accessible, so why does this fail?

Because the document does not say so. The conformance marker is a separate assertion from being conformant, and it has to be written into the file. This is one of the requirements that exists purely as file bookkeeping, and it is also one of the easiest to satisfy once the real work is done.

The metadata was there and has disappeared

Something rewrote the file. Merging, compressing, flattening, redacting, and signing are the usual culprits, and any step that produces a new PDF can drop the record. Where a publishing pipeline has several stages, check the metadata at the end of it rather than after export.

Why is this a PDF/UA requirement rather than a WCAG one?

WCAG describes what a reader must be able to do, and no reader is affected by a conformance marker directly. It is part of PDF/UA because PDF/UA specifies how the file is built, including how it identifies itself. See Understanding PDF accessibility.

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