Examples
Worked examples
- Is an instance
A national or disciplinary archive that has already achieved CoreTrustSeal (core level) applies separately for the nestor Seal, submitting evidence against DIN 31644's 34 criteria across organisational framework, object management, and infrastructure/security, without yet pursuing a full ISO 16363 audit.
- Is an instance
The nestor Seal for Trustworthy Digital Archives itself — awarded by Germany's nestor competence network after a plausibility-checked self-assessment, typically completed in around three months — is the concrete, currently-operating instance of extended level certification.
Counter-examples
Looks similar, but isn't
- Not an instance
Holding CoreTrustSeal alone is core level, not extended level — CoreTrustSeal's 16 requirements and lighter peer-review process are a different, less demanding tier than the nestor Seal's 34 DIN 31644 criteria.
- Not an instance
An ISO 16363 certification is formal level, not extended level — it requires assessment by an accredited external auditor against a much larger evidence-based framework, rather than a repository's own (even if plausibility-checked) self-assessment.
Editorial commentary
Extended level certification is the middle tier of the widely-cited three-tier framework for assessing whether a data repository is trustworthy, sitting between CoreTrustSeal‘s core level and a full ISO 16363 audit. In practice, extended level is delivered by the nestor Seal for Trustworthy Digital Archives, based on the German standard DIN 31644 (“Criteria for trustworthy digital archives”) and administered by the nestor competence network, hosted at the Deutsche Nationalbibliothek (German National Library).
Where core level certification (CoreTrustSeal) is a lightweight, peer-reviewed self-assessment against 16 published requirements, extended level is a more demanding plausibility-checked self-assessment against 34 DIN 31644 criteria, organised into three areas: organisational framework, management of intellectual entities and their representations, and infrastructure and security. It is still self-directed by the repository rather than conducted by an accredited external auditor — that step up in rigor is reserved for formal level (ISO 16363).
References
- nestor (Kompetenznetzwerk Langzeitarchivierung), ‘nestor Seal for Trustworthy Digital Archives’, based on DIN 31644:2012, langzeitarchivierung.de.
- Digital Preservation Coalition, ‘Audit and Certification’, Digital Preservation Handbook, dpconline.org.
- CoreTrustSeal Foundation, materials describing the tiered core/extended/formal certification landscape, coretrustseal.org.
Also known as
nestor Seal · DIN 31644 certification · Extended-level trust certification
Machine-readable encodings
Use in your systems
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