# Rights, Licensing & Redistribution — SONAR packaging

**Status:** packaged and rehosted under a *maintainer-asserted* license. Read this before
relying on the data for anything beyond non-commercial research.

## What this repo is

A re-encoded, schema-normalized packaging of the **SONAR** synthetic-audio detection
evaluation set (arXiv [2410.04324](https://arxiv.org/abs/2410.04324); upstream code/data:
[github.com/Jessegator/SONAR](https://github.com/Jessegator/SONAR)). 4,548 clips: 2,274
bonafide (LibriTTS clean-test) + 2,274 spoof from nine speech-synthesis systems.

## The rights situation (be honest about it)

SONAR has **no unified upstream redistribution license**:

- The paper explicitly declines one: the constituent sources "may be subject to different
  distribution licenses and usage restrictions," and it directs users to "the usage policies
  of the respective API providers."
- The official upstream repo has **no `LICENSE` file** and no redistribution statement.
- The spoof set aggregates output from systems with their own terms — notably **OpenAI TTS
  API** output (600 clips), whose API Terms of Service restrict redistribution — alongside
  xTTS, Seed-TTS, VALL-E, VoiceBox, NaturalSpeech 3, PromptTTS 2, FlashSpeech, AudioGen. The
  bonafide side is **LibriTTS** (CC BY 4.0).

We therefore **cannot point to an upstream grant** that clearly permits rehosting these audio
bytes.

## What we asserted, and why

This packaging is published under **CC BY-NC 4.0** (full text in `LICENSE.txt`) as the
**safest defensible choice** for an aggregated research benchmark we can't relicense
permissively:

- **NonCommercial** narrows exposure on the commercial-API-derived portion (OpenAI TTS).
- **Attribution** preserves credit to the upstream sources and the SONAR authors.

**This is a packaging license applied by the Arena maintainers, not an upstream grant.** The
underlying sources retain their own terms. CC BY-NC 4.0 here is an assertion *over an aggregate
we do not hold full rights to* — it reduces, but does not eliminate, redistribution risk.

## For downstream users

- Use is intended for **non-commercial research / benchmarking only**.
- If you need stronger guarantees, **regenerate the spoof audio yourself** from the upstream
  recipes in `github.com/Jessegator/SONAR` rather than relying on this rehost, and consult each
  provider's usage policy (OpenAI, Coqui/xTTS, etc.).

## For maintainers / takedown

If any upstream rights-holder (OpenAI or any synthesis-system owner) objects, treat this as a
**takedown candidate**: depin the dataset from `arena-manifest` (remove the `core_set` entry +
add a `dataset_repin`/note CHANGELOG event) and delete or gate the HF dataset repo. The
labels/protocol are ours; the audio is the encumbered part. The cleaner long-term fix is a
loader that regenerates spoof audio on the user's side instead of rehosting it.

_Recorded 2026-06-07 alongside the SONAR add. See also the dataset card's "License &
redistribution" section and `docs/plans/2026-06-07-sonar-arena-dataset.md`._