Including Custom Metadata Structures in PDF
Many industries and organizations define various metadata schemes beyond those specified in ISO standards for PDF technology.
In PDF, all such third-party schemes are “custom metadata”, often existing as manifest files in various serialization formats supporting existing complex workflows and systems. Organizations leveraging these metadata in the PDF context can benefit from guidance regarding appropriate method(s) for including their custom metadata in PDF documents, enabling smoother and more efficient workflows and avoiding “sidecar files” or less user-friendly ZIP archive-based solutions.
This Application Note presents methods for incorporating custom metadata structures into PDF files. It provides recommendations and guidance to assist organizations in selecting the most suitable mechanism(s) for storing their custom metadata manifests in PDF documents, consistent with ISO standards for PDF.
A basic understanding of PDF is assumed.
NOTE: This Application Note focuses on larger custom metadata schemes and thus does not provide detailed advice on other mechanisms more appropriate for lightweight or small custom metadata data points.
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Published by the PDF Association © 2025
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