A X N
WHY THIS EXISTS · MEASURED, NOT ASSERTED · PID EROSION OBSERVATORY
Evidence Identifiers stop being identifiersregistry scale
measured by the PID Erosion Observatory · dated captures preserved

A persistent identifier is a maintained relation, not a string. When the maintenance stops, the string survives and the relation does not — and it stops silently. These are counts, not opinions.

THE STRINGS PERSIST 1,309,351 REMOVALS THE RELATION DID NOT COMPUTED FROM THE OBJECT
An identifier is a maintained relation, not a string. When the maintenance stops the string survives and the relation does not — silently. One thread holds: the kernel is computed from the object, so nothing has to maintain it.
1,309,351
removal events in a single registry's deletion export (ZD-S1)
92.14%
of those removals carry no citation record — deletion leaving no trace of what was deleted

An identifier a company can revoke was never persistent. It was permitted. An AXN is computed from your bytes, so there is nothing to revoke — and no one to ask.

Founding case What it looks like from insiden = 1,817
this archive was one of those deletions · audited afterward, published as a paper

In June 2026 a repository terminated this archive's account. Roughly 870 deposits went with it. The figures below are from an audit of our own wreckage — which is how the observatory started.

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871 of 1,817 DOIs

measuredpublic metadata absent from the registry API
aftertwenty days, zero restorations

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0 of 54 sampled deletions

presentin the OpenAIRE research graph
yet92% persisted in OpenAlex — erasure propagates unevenly

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229 recorded captures

observinghow machine composition layers describe this work
notarguing with them — recording what they said, and dating it

How it works →What it does not claim →
the observatory EA-MPAI-DOI-IMPERMANENCE-01 · #868 · AXN:0371.EMPIRICAL.👋☁️⛩️☄️🤙📝 the capture registry
∮ = 1