Rights & Permissions

The five badges

• Rights: Public domain (US) (6 Index records)
  Published before 1931, or otherwise shown to be in the US public domain, with written evidence. It may not be public domain in your country. Download and reader buttons are shown.
• Rights: Open license (0 Index records)
  Released under an open license (Creative Commons or CC0). The license is linked in the evidence and its terms apply. Download and reader buttons are shown.
• Rights: Permission granted (0 Index records)
  The rights holder gave written permission. The date of the permission is in the evidence. Download and reader buttons are shown.
• Rights: Link only (4,149 Index records)
  In copyright or restricted. We link to the record’s book page on isidore.co, never to its files. No download or reader buttons.
• Rights: Unknown (2,478 Index records)
  Not yet reviewed, or the evidence is not strong enough. Treated as link only until a person checks it. No download or reader buttons.

For Link only and Unknown records we link only to the record’s book page on isidore.co, never to its files or to isidore.co’s folder listings. Bibliotheca Catholica does not host, and does not vouch for, any file at isidore.co. Hover over or tap a badge to see the evidence and the date it was checked; a record’s own page shows the same details.

How the status is decided

• Reading-room texts. Each text we host was checked edition by edition before it was added: the specific edition or translation must have been published before 1931, and the evidence is recorded with the edition. These show Public domain (US).
• Isidore Index records. Each record was classified on 2026-10-25 from its catalog year, ISBN, publisher, and an automated match against the NYPL transcription of US copyright renewals. Records presumed in copyright (for example, a 1978 or later edition, an ISBN with no year, a renewed 1931–63 book, or a post-1930 papal or curial text) are Link only.
• Leads are not decisions. A pre-1931 catalog year, a public-domain source named in the catalog, or “no renewal found” is a lead for a person to check, not proof. Catalog years are often scan or reprint dates, and a modern reprint can add a protected translation, introduction, or notes. Until someone checks the title page and the evidence, these records are Unknown.
• The only automatic public-domain records in the Index are the same Project Gutenberg texts that our reading room hosts after a rights check.
• When in doubt, the status is Unknown. A status changes only with written evidence (a URL, a quotation, or a renewal-record citation) and the date it was checked.

The checked date

Each badge shows when its status was last checked. Copyright status changes over time (each 1 January more US works enter the public domain), and our evidence can improve, so an older date means “as of then”.

The 1931 rule still applies

We host a full text only if that edition was published before 1931 and its rights were checked. Anything later is a link to its source, whatever its badge. A badge of Public domain (US) refers to the United States; the book may not be in the public domain in your country.

Rights are not recommendations

A rights badge says nothing about a book’s content. The Fidelity & Editorial Policy still applies: listing is not endorsement, flagged titles keep their context note, and flagged titles are never featured.

Corrections and removal

If a badge is wrong, or you hold the rights to a work and want a link or a text removed, see Takedown requests. Data: each record’s rights_status, rights_evidence, and rights_checked are in the Open Data.

This is not legal advice. It explains how this library labels and links books. If you need advice about a particular work, ask a lawyer.