Public-Domain Verification Process

1. Policy: United States public domain only

Attacca ingests, stores, and serves only musical scores it has assessed, file by file, to be in the public domain in the United States. A file that may be public domain in another jurisdiction but not the United States is excluded from the catalog entirely. This is deliberate conservatism. Attacca operates from the United States, and a single strict standard is simpler to verify, to audit, and to defend than a per-jurisdiction model.

2. Verification pipeline

Files are checked at every stage from ingestion to delivery. Source review supplies the initial copyright data; three independent gates then exclude any file that is not assessed as United States public domain, at ingestion, at download, and at catalog inclusion, so a file that fails any one of them is excluded from serving. A fourth gate governs serving, delivering only the already-cleared catalog through authenticated, metered access. When a gate gap or a mis-admitted file is identified, it is corrected promptly and the correction is logged; the audit record is what makes those corrections demonstrable.

• Source review. Each file in the source archive carries a per-jurisdiction copyright-review tag. That tag is the starting datum, not the final word.
• Gate 1, ingestion scope. Our extraction step reads the per-file tag and places a file on the download list only where that tag indicates United States public domain.
• Gate 2, downloader. The crawler enforces the same check independently and refuses to store any file absent from the verified list. The check is enforced in code and cannot be bypassed silently.
• Gate 3, catalog build. A file enters the catalog only if its individual US-public-domain verdict holds. The verdict is per file, not per work (see Section 4).
• Gate 4, serving. Only files that passed Gate 3 enter the catalog. Files are served solely through authenticated, metered download grants, never directly, and each retains its per-file audit record. Attacca applies one United States public-domain standard uniformly and does not detect or filter by a visitor's location. Public-domain status can differ outside the United States, and users there are responsible for compliance with their local copyright law, as set out in our Terms.

3. Audit log

Attacca maintains a durable, per-file audit record.

For each file examined, the record captures:

• the source URL;
• the date the file was examined;
• the raw upstream copyright tag;
• the resulting per-jurisdiction public-domain verdict;
• the ingestion decision, admitted or excluded, and on what basis.

The log accumulates over time and is not overwritten. For any file in the catalog, Attacca can therefore state on what basis, and on what date, it was judged to be in the public domain. This is what makes the process auditable rather than merely asserted.

4. Edition-level copyright

Public-domain status is judged at the level of the individual digitized file, never the composer or the composition alone. The most common error in score reuse is to treat a public-domain work as though every edition of it were equally free. A modern critical or engraved edition of a public-domain composition carries its own copyright. Attacca's per-file gate is built specifically to exclude such editions, even when the underlying work is unambiguously in the public domain. Such editions are excluded on the strength of their own copyright status, whether or not the underlying composition is in the public domain.

5. Editorial originality and re-engraved editions

Attacca serves only files that are individually verified as United States public domain. It does not rely on any theory that urtext, scientific, or re-engraved editions of a public-domain composition lack copyrightable originality of their own. A file whose United States public-domain status would depend on such an argument, rather than on the file's own verified public-domain status, is excluded from the catalog and is never served.

If you believe any specific edition has been incorrectly classified, please contact us through the DMCA process.

6. Foreign works and URAA restorations

Foreign works first published between 1923 and 1977 receive elevated scrutiny. The Uruguay Round Agreements Act of 1994 (URAA) restored United States copyright on foreign works that remained under copyright in their source country on January 1, 1996. A work that appears to be US public domain by publication date alone may in fact be subject to URAA restoration, with US copyright extending until 95 years after first publication.

This is the area of United States public-domain analysis that most often produces close calls. We are currently reviewing and strengthening how our ingestion process evaluates this category. While that review is under way, our approach is conservative removal: any file whose United States status is in question is withdrawn from the catalog pending re-verification rather than served while the question is open. If you believe a specific work or edition is incorrectly available, please contact us through the DMCA process and we will act on it promptly.

7. Content sourced through institutional partnership

For scores obtained through a partnership, the partner institution's own public-domain determination is the primary basis for inclusion. A library that digitizes only works it has itself determined to be in the public domain, under a documented and conservative standard, arrives pre-vetted. Attacca's gates and audit log then serve as a documented confirming check rather than an independent re-adjudication, and every item permanently retains its source identifier as a provenance link back to the originating institution.

8. Legal posture

For the catalog, Attacca's position rests on substance rather than procedure: content is admitted only on a documented, good-faith determination that it is in the public domain in the United States, so that for any file Attacca can show the basis on which no copyright is infringed. The verification pipeline and the audit log exist to make that basis demonstrable, file by file. Should a mislabeled file ever be identified, Attacca can remove it from the catalog promptly, and will do so on any credible report, with the audit log preserving the basis of the original decision for review. Conservatism in what is admitted, documentation of every decision, and prompt correction are treated as the core of responsible operation.