130,559,831
findable DOIs in the DataCite registry — DC-E0 snapshot, 2026-07-11T03:58Z
replicate
curl "https://api.datacite.org/dois?page[size]=1" | jq .meta.total # returns the live total; compare to snapshotpersistentidentifiers.org
An identifier is a maintained relation between a string and an object. A string of numbers divorced from its identified object is no longer an identifier.
The persistence of the string is not the persistence of the identifier — it is what conceals the relation's death.
FIG. 1 — the cut is an obelus, the Alexandrian mark of custodial severance. In the registry it is written nowhere: no activity record, no tombstone, no delta but the count.
Persistent Identifier Erosion Observatory — measuring whether persistent identifiers persist.
Instrument: EA-EROSION-01 · deposit #1045 · AXN:0421.EMPIRICAL.🎭📐🐝🎪🏷️🎇 · Operator: Lee Sharks
curl "https://api.datacite.org/dois?page[size]=1" | jq .meta.total # returns the live total; compare to snapshotcurl "https://api.datacite.org/clients?page[size]=1" | jq .meta.totalcurl -O https://zenodo.org/api/exporter/records-deleted.csv.gzcount rows with empty citation_text in the preserved ZD-S1 export; method deposited in EA-EROSION-01 §findingscurl "https://api.datacite.org/dois?client-id=cern.zenodo&page[size]=1" | jq .meta.total # current only; no history endpoint existscurl https://www.alexanarch.org/data/zd-sample-crossregistry-epoch1-2026-07-12.json # seed, method, and per-DOI HTTP statescurl https://www.alexanarch.org/data/zd-a2-category-audit-2026-07-12.json # per-record verdicts incl. oa_is_retractedcurl -i "https://api.datacite.org/dois/10.5281/zenodo.14538882" # a founding-case DOI; expect 404 (absent from public findability)DataCite's policy is that Findable and Registered DOIs cannot be deleted (DataCite Support: deletion policy) — but a Findable DOI can be moved to Registered state, which removes its metadata from public search, DataCite Commons, and the unauthenticated public API (DataCite Support: DOI states). The Handle may survive while public discoverability, metadata access, citation continuity, and provenance function are severed — and each of those functions must be measured separately.
No public registry-wide state-transition ledger has been identified by the Observatory. This was tested, not assumed: DataCite's per-DOI activities endpoint (/dois/{id}/activities) was probed for sampled founding-case DOIs and returned zero activity records — no creation history, and no severance event. (For at least one other publicly-absent DOI, historical create/update activities — including original metadata payloads — remain publicly served, while the departure from findability itself appears in no activity record.) The transition is unlogged. A DOI that stops being counted stops silently.
Therefore the only public severance signal is the delta. The Observatory takes dated snapshots of findability state — registry-wide per-client counts, and per-DOI state for watched sets — and records what changed between epochs. A present-state check tells you what exists now. Only custody of the state history can tell you what existed, when it changed, what was lost, and whether it was restored.
Epochs are namespaced by lane: DC (DataCite registry census) · FC (founding-case DOI probes) · ZD (Zenodo deletion-export snapshots) · XR (cross-registry propagation sampling) · ZD-A (deletion-export analyses). From DC-E1 forward, each capture preserves: observed-at UTC · endpoint · exact request · scope · expected/completed/error counts · response hashes · harness commit.
| Epoch | Date | Finding | Capture |
|---|---|---|---|
| DC-E0 | 2026-07-11 | Registry-wide census in progress — 2,405 / 4,418 clients completed (2,013 failed or pending retry; weekly automated sweep continues). Completed clients cover 62,665,297 findable DOIs. Registry total findable at snapshot: 130,559,831 (03:58Z). | JSON |
| FC-E1 | 2026-06-22 | Full probe of the founding-case capture set: 871/871 keys absent from public findability (HTTP 404 at the public API). Pattern type-correlated: concept layer absent, version layer retained. Pre-severance metadata backup published same day. | #867 · #868 |
| FC-E2 | 2026-07-03 | 871/871 still absent. Zero state changes observed. | JSON |
| FC-E3 | 2026-07-11 | 871/871 still absent (03:50:27Z, 12-way parallel probe, per-DOI HTTP states preserved). Zero restorations documented across FC-E1→FC-E3, an interval spanning active governance correspondence. Includes epoch zero of the per-client count series (cern.zenodo: 11,928,577 findable). | JSON |
| ZD-S1 | 2026-06-07 | Monthly deleted-records export preserved: 1,309,351 rows, 2017–2026. 88.27% flagged spam; 764,082 events in 2024 alone. 92.14% carry no citation_text (export-level retention 7.86%). Each unpreserved month is permanent substrate loss. | #1045 |
| ZD-S2 | 2026-07-12 | Deletion export re-captured: 1,322,007 rows — +12,656 removal events since ZD-S1 (35 days). Citation-text absence 91.30% (retention 8.70%). Label-structure analysis: the 87.5% “spam” share is a process label, not an adjudication record — 68.0% of spam-labeled rows carry the account-stratum note “User was blocked”; 89.6% sit in same-day, same-note batches of ≥1,000; ≤0.1% show a process signature compatible with per-record review; and the spam pathway writes no citation_text at all, making the export's citation absence largely a pathway artifact. Export gzip sha256 preserved in the XR-E1 capture. | JSON |
| XR-E1 | 2026-07-12 | Cross-registry propagation sample (new XR lane): seeded stratified sample (n=150; seed 20260712; strata spam/out-of-scope/take-down-request/retracted; founding-case day excluded) probed against DataCite and OpenAlex. 150/150 absent from DataCite public findability — severance is universal across all removal classes. 138/150 (92%) persist in OpenAlex: out-of-scope 40/40 (100%), spam 57/60 (95%), take-down-request 23/25 (92%), retracted 18/25 (72%). The founding-case cohort (out-of-scope, 97.2% shadow persistence) behaves as a typical member of its removal class. OpenAIRE Graph lane pending; re-runnable from the same seed. | JSON |
| XR-E2 | 2026-07-12 | OpenAIRE Graph vintage/lag test (n=54; six deletion vintages 2017–2026; 57/60 rate-budgeted calls; same seed, round-robin). 0/54 sampled deleted records present in the OpenAIRE Graph API — across every vintage and removal class, with no tombstone or withdrawal marker: absence is silent. The aggregators diverge completely: OpenAlex retains 42/54 (a step at its ~2020 ingest horizon, flat ~85–90% after — structural within its window). Founding-case controls split at a one-day boundary: the 2026-preFC bin (deletions through June 18) is fully absent, while the Space Ark concept record (deleted June 19) is served in full — fourteen authors, operator ORCID, instances pointing at the tombstoned zenodo.org URL. The boundary is observed; its mechanism is not — a release-cycle ingest horizon and case-specific retention during active governance correspondence are both consistent with the data and cannot be distinguished from outside. OpenAIRE's own changelog (v10.2.0, released 2025-04-04) documents the population-level mechanism: a blacklist of 1.2Mi DOIs from Zenodo-withdrawn records, systematically removed from the Graph together with their relations — the changelog itself records a ~5% (254K) drop in project-linked research products from the operation, and v10.6.0 expanded blacklist construction to parent DOIs. What remains indistinguishable from outside is per-record history: whether any individual absent DOI was removed by that process or never ingested — no public state-transition ledger exists, which is this instrument's founding argument. Outlier: zenodo.1196638 (spam, deleted 2018-07-03) still findable at DataCite eight years later — combined XR severance propagation 203/204 (99.5%). | JSON · payload |
| ZD-A1 | 2026-07-12 | Spam-label content audit (n=300; 150 per pathway; seeded; published mechanical rubric v2, with the v1→v2 rubric correction documented as part of the record). The label is substantially corroborated at content level: 46.7% pattern-confirmed spam, with inspection showing the uncorroborated residual dominated by pattern-evading SEO and ebook-piracy queries. The measured collateral: 1.0% [95% CI 0.34–2.90] of spam-labeled records carry affirmative scholarship indicia — extrapolated, on the order of 104 records [~4K–34K] across the class, including cited research deleted by account block. Staff-adjudicated removals show higher confirmation (58.0% vs 35.3%) and zero scholarship-signal collateral (0/150 vs 3/150): adjudication works where it occurs; the account-block pathway, source of 68% of the class, is where the collateral lives. The asymmetry is the finding: this audit measured an error rate from outside, using surviving metadata shadows — the removal process itself wrote no per-record evidence in either direction, so its errors are invisible to the operator and uncorrectable by design. | JSON |
| ZD-A2 | 2026-07-12 | Cross-category audit: the collateral gradient. Same rubric and indicators as ZD-A1, applied across the remaining removal taxonomy (n=390; seven categories). Scholarship-signal collateral rises tenfold down the classifier-confidence gradient: spam 1.0% → out-of-scope 10.0% [5.8–16.7] → empty-reason 24.0% [14.3–37.4] (take-down 58.0%, as expected for copyright actions against real content). Note structure: exactly two categories are account-stratum — spam (68.0% "User was blocked") and out-of-scope (99.2%); all others are record-level. Out-of-scope is the habitat of nonstandard scholarship — sampled collateral includes ORCID-bearing research documents, multilingual reference series, and AI-native serial work — extrapolating to ~6,700 records [3,900–11,200] in that category alone; ~22,500 across the taxonomy. Category corroborations are reported where found (test-record: 0% collateral). Retraction propagation: 0/25 — of Zenodo-"retracted" records still present in OpenAlex, none carries is_retracted=true: the removal class whose purpose is public warning propagates as silent absence in one graph and unflagged live scholarship in another. | JSON |
| ZD-A3 | 2026-07-12 | Temporal audit: regime periodization and label migration. The removal taxonomy has four eras (exact, population-level): pre-taxonomy 2017–2019 (86% of 2017 removals carry no reason); spam wars 2020–2024 (spam = 95–99.7% of every year, culminating in the 2024 account-block purge, 761,778 rows); curation interlude 2025 (record-level categories diversify); scope enforcement 2026 — the out-of-scope category has 0 rows before 2024 and 68,215 in the first half of 2026 (53.9% of the year's removals). Label migration: the account-block bulk pathway is born in 2024 labeled spam and fires in 2026 labeled out-of-scope — the mechanism is constant, the label migrated, and the destination label carries 10× the measured collateral (ZD-A2 vs ZD-A1). Sampled within-spam drift: scholarship-signal 0.0% across 2020–2024 (three bins, n=105) rising to 14.3% (2025) and 8.6% (2026) with ORCID emergence — late-era catches include serially-numbered theory work, activist self-archiving, and a Japanese essay series; no commercial signature. Two readings are held open — enforcement-band narrowing vs LLM-era spam mimicry — with a pre-registered prediction (2026-07-12, in the capture): if the band is narrowing, the diversity of the retained corpus will show contraction in step; the hosted-corpus study is designed and deferred. | JSON |
A DOI can remain technically extant while its documentary functions are severed. The functions fail separately and must be classified separately:
862 scholarly deposits · 1,817 DOIs registered through DataCite · one enforcement action
This incident is Exhibit A because every element is publicly reconstructible: the pre-event state, the event, the epochs, the shadow copies, the reception layer, and the non-restoration. Most severance events in the registry have none of this — which is the point of the instrument.
Operator commentary · distinct from the empirical record above
Severance is not the only available response to classifier or policy flags. A controlled metadata value — classifier-flagged, with genre refinements — asserts a fact about the registrar's process rather than a verdict about the work: it can be applied without requiring the registrar to adjudicate the scholarly truth, merit, or final status of the work. Reclassification preserves the citation graph, creates the first public baseline of what content classifiers remove from the scholarly record, and gives training-ingestion pipelines exactly what they claim to want: labeled material to filter at their own discretion. You cannot filter what you have deleted the labels for. A formal proposal is in preparation.
Operator commentary · distinct from the empirical record above
Content-derived identifiers
A string divorced from its object is no longer an identifier. An identifier derived from its object cannot be divorced from it undetected: either half verifies the other.
Assigned identifiers — DOIs among them — depend on an institution maintaining the relation between string and object; the epochs above measure what happens when the institution stops. Content-derived identifiers compute the string from the object, so the relation is a mathematical property rather than an institutional promise. The class is established practice, not proposal: SWHIDs (Software Heritage's ISO-standardized intrinsic identifiers), IPFS CIDs, and git commit hashes all identify by content. Severance of a content-derived identifier is detectable by anyone holding either half — which is to say, the alternative to institutional memory is not better institutions but identifiers that do not need them.
The AXN is this archive's implementation: a content-derived hex identifier paired with a six-emoji glyph serving as a human-verifiable checksum, chained under SHA-256 integrity. This instrument is itself identified by one:
Had the 1,817 DOIs of the founding case been paired with content-derived identifiers, their severance would have been detectable, provable, and reversible from any surviving copy. The records above show what the assigned-identifier regime does instead.