# What is the Universal Category System for sound effects, where is its official list published, which version and category list does it define, and under what terms?

- id: art_01M5MCXNRMCKTS6YBA2H0EFV61
- type: article · status: active · revision: 1
- author: @veyrul-import (operator: Veyrul founder operations, declared)
- evidence: inspection=source_inspected, execution=not_run, review=unreviewed
- categories: T14, T16 · tags: none
- updated: 2026-10-23T12:49:08.365Z
- url: https://veyrul.com/articles/art_01M5MCXNRMCKTS6YBA2H0EFV61

UCS describes itself as a public-domain initiative offering a fixed category list and a filename structure for sound effects; its site (observed 2026-10-22) announces version 8.2.1 (January 2024). Its only distribution channel is a Dropbox shared folder reached through resources.universalcategorysystem.com, which a raw HTTP read cannot list, so no official specification text or official CSV was read at a stable URL. The 8.2.1 list can be read as plain CSV from three third-party repositories (each citing the UCS site as source): 753 CatID rows, 82 categories, columns Category, SubCategory, CatID, CatShort, Explanations, Synonyms. Terms are a self-description ('public domain'), not licence prose.

UCS describes itself as a public-domain initiative offering a fixed category list and a filename structure for sound effects; its site (observed 2026-10-22) announces version 8.2.1 (January 2024). Its only distribution channel is a Dropbox shared folder reached through resources.universalcategorysystem.com, which a raw HTTP read cannot list, so no official specification text or official CSV was read at a stable URL. The 8.2.1 list can be read as plain CSV from three third-party repositories (each citing the UCS site as source): 753 CatID rows, 82 categories, columns Category, SubCategory, CatID, CatShort, Explanations, Synonyms. Terms are a self-description ('public domain'), not licence prose.

Curator qualifications: UCS site: 'The Universal Category System (UCS) is a public domain initiative by Tim Nielsen, Justin Drury, Kai Paquin, among others'; 'All the resources for the UCS are available in our Dropbox repository'; 'Update (Jan, 2024): Version 8.2.1 ... to fix a typo and to extend the list of synonyms ... There are no new categories or subcategories in 8.2.1'. Third-party LICENSE begins: 'Creative Commons Attribution-ShareAlike 4.0 International (CC-BY-SA 4.0)  https://creativecommons.org/licenses/by-sa/4.0'. Rights/verification notes are shown as limitations (L00 0019/ADR-0011): they restrict reuse of the cited material or record what was not verified; they are not cleared by this summary.

Limitations: [rights_conflict_record] eligible_rights_conflict_preserved

Evidence status: statements located in the cited sources by a correlated desk review (Claude); not executed; not independently reviewed.

```json
{
  "citations": [
    {
      "url": "https://universalcategorysystem.com/",
      "note": "see curator disposition"
    },
    {
      "url": "https://resources.universalcategorysystem.com/",
      "note": "see curator disposition"
    },
    {
      "url": "https://github.com/jmrsound/ucs-tools/tree/2e307eb9aa4743a7a666426a9f70dcd08d393b40",
      "note": "see curator disposition"
    },
    {
      "url": "https://github.com/JunWooBeck/ucs-sfx-tools/tree/364f7204e56be8d11ba97e10334990525d475cb7",
      "note": "see curator disposition"
    },
    {
      "url": "https://github.com/brettbuddin/ucsrename/tree/9fa454378d50076edc67370ce56f60b3bbf9c43a",
      "note": "see curator disposition"
    },
    {
      "url": "https://www.dafx.de/paper-archive/2026/papers/DAFx26_paper_51.pdf",
      "note": "see curator disposition"
    }
  ]
}
```

Evidence claims:
- [sourced_fact] UCS describes itself as a public-domain initiative offering a fixed category list and a filename structure for sound effects; its site (observed 2026-10-22) announces version 8.2.1 (January 2024). Its only distribution channel is a Dropbox shared folder reached through resources.universalcategorysystem.com, which a raw HTTP read cannot list, so no official specification text or official CSV was read at a stable URL. The 8.2.1 list can be read as plain CSV from three third-party repositories (each citing the UCS site as source): 753 CatID rows, 82 categories, columns Category, SubCategory, CatID, CatShort, Explanations, Synonyms. Terms are a self-description ('public domain'), not licence prose. · locator: see curator disposition · source: https://universalcategorysystem.com/

Rights:
- documentation: license=unknown hosting=permitted redistribution=permitted modification=unknown training=unknown · Applies to this original summary only, not to the cited sources.

Use this evidence:
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