# Licensing

CiteLink combines material under four different regimes. Treating them as one
would be wrong in both directions — some of it is freer than the code, and some
of it is not ours to license at all.

## Bibliographic data — CC0

The article, author and institution records, and every column of the journal
records **except the index-coverage flags**, come from
[OpenAlex](https://openalex.org), released under a
[CC0 1.0](https://creativecommons.org/publicdomain/zero/1.0/) public-domain
dedication. We add no restriction on top. Take it, redistribute it, build on it.

## Index-coverage flags — twelve sources, four regimes, two open questions

Until 7 September 2026 the paragraph above said "the journal records", full stop.
That was true when a journal row held only OpenAlex bibliography. It stopped being
true as flags from twelve indexes were added to the same table, and the sentence
was left standing — so it is corrected here rather than quietly.

`in_scopus`, `in_wos`, `is_in_doaj`, `in_pubmed`, `in_pmc`, `in_ebsco`,
`in_trdizin`, `in_eric`, `in_kci`, `in_erihplus`, `in_scielo`, `in_ajol` and the
fields beside them each say whether one journal appears in somebody else's index.
The per-flag table in **[data.html §8](https://www.citelink.org/data.html#licence)**
names, for each one, the endpoint we actually read and what its publisher says
about reuse. Four things belong here rather than there:

**Most of them ask nothing.** DOAJ waives all rights in its journal metadata
(CC0) and expects no attribution; `is_in_doaj` reaches us through OpenAlex, which
is CC0 as well. Crossref calls bibliographic metadata "facts, not subject to
copyright" and releases its own aggregations — which is what the ISSN facet behind
`in_ajol` is — as CC0. ERIC is published by IES for public use. Korea's open-data
portal declares dataset 3049043 with no restriction on the scope of use.

**NLM asks, and asking is enough.** Works of the U.S. government carry no
copyright in the United States, and NLM's web policy says "Please acknowledge NLM
as the source". We do, on data.html and here: *Courtesy of the U.S. National
Library of Medicine.*

**Two are not ours to pass on.** `in_wos` comes from Clarivate exports obtained
under an institutional subscription; Clarivate forbids redistribution of its
content without written consent, and an institutional agreement governs on top.
`in_scopus` comes from Elsevier's public workbook, whose terms prohibit systematic
retrieval to compile a database without prior written permission. **We do not have
that permission and have not yet asked**; a letter is drafted and unsent. Neither
flag is offered here under any licence of ours, and anyone redistributing them
should read those operators' terms.

**And one is an unresolved conflict, on 8,377 journals.** `in_erihplus` comes from
the Zenodo deposit 10.5281/zenodo.8163337 — a snapshot dated 27 April 2023,
published 19 July 2023 by the depositor "ERIH-PLUS" — and that record carries
**CC BY 1.0 Generic**. The operator's own site says something different: *"The
content in erih+ is licensed under CC BY 4.0 Non Commercial."* CiteLink is
commercial. Those two statements cannot both govern our use, and we are asking
HK-dir which does. Until they answer, this flag rests on the Zenodo deposit alone,
and we say so rather than picking the reading that suits us.

## What the API actually gives you

One sentence in an earlier draft of this file said we hold "one value per journal
and never the list". It described a table and was offered as a description of the
service, and as that it was false. Correctly: the flags are filterable on the
public route and the response carries an exact count, `assets/data/catalog.json`
ships every flag for all 63,664 records in one file, and four of the flags are
more than a boolean — `scopus_source_id` (30,239 journals), `wos_editions`,
`wos_categories`, `wos_abbrev`, `ebsco_dbs` and `kci_tier`. A reader can get close
to a reconstruction of somebody's index from this API. Whether that access should
change is an open question; whether this file describes it accurately is not.

## Metrics we compute — CC BY 4.0

CNI, percentiles, the C1–C4 quartiles, self-citation rates, the Crossref deposit
scorecard and the CiteLink Value are derived by us and released under
[CC BY 4.0](https://creativecommons.org/licenses/by/4.0/).

Attribution must name **the edition**, not just CiteLink. A quartile from one
citation snapshot is not comparable with one from another, and a figure quoted
without its edition invites exactly the misreading the methodology works to
prevent. For example: *"C1 in Immunology, CiteLink edition 2026-07."*

## Site code — not yet licensed

The HTML, CSS, JavaScript and ETL scripts in this repository carry **no licence
yet**. That is a deliberate placeholder, not an oversight: publishing a licence
grants rights that cannot be withdrawn, and the choice belongs to the owner.

Until a licence is chosen, default copyright applies — all rights reserved. If
you want to reuse the code, ask.

## Third-party material

The site JavaScript is original work. `assets/css/style.css` is our own CSS, **but
the index marks in it are other people's trade marks**, and there are more of them
than an earlier version of this section admitted.

Three are the operators' own files, embedded as `data:` URIs so they load without a
request to anyone: **TR Dizin** (TÜBİTAK ULAKBİM), **ERIC** (US Dept of Education,
IES) and **ERIH PLUS** (HK-dir). The rest are **redrawings** — the stylesheet's own
comment puts it plainly: *"Every other index mark in this stylesheet is a traced
SVG"* — which covers the DOAJ leaf, the open-book device in the PubMed wordmark and
the PMC pediment among others. A redrawing of a mark is still a use of that mark.

All of them are used nominatively: to say which index a journal is in. We assert no
rights in any of them, we do not suggest that any of these organisations endorses
CiteLink, and if an operator asks us to stop using its mark we will replace it with
the index's name set in type.

No vendored third-party code bundles remain in this repository; four that had been
saved here by accident during research were removed on 22 August 2026.

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*Questions about reuse: info@citelink.org*