Phonon-2 is CC-BY-4.0: what attribution means for shipped transcripts

Phonon-2, released on September 29 by Fermion Research, is offered under CC-BY-4.0, and the model page says commercial use is permitted with attribution. In practice that means you may bundle the model in a paid app, but you owe credit to the author. This is a reading of the vendor's page, not legal advice; read the full licence text before you ship.

One detail is easy to miss. CC-BY-4.0 attaches to the model and its distribution. Whether a transcript produced by the model needs a credit line is a question for the licence text and your counsel. What is certain is that the app that bundles or redistributes the model needs the notice.

What to check before you ship

The list below is a practical review checklist, not a legal rule set.

• Keep the licence file and author credit in the app bundle.
• Add the credit in your about screen or open-source notices page.
• Record which model version shipped, so a later release can match it.
• Do not rename the model in a way that hides its source.

The hosted alternative

With a hosted API there is no model file to redistribute, so there is no model notice to carry. You still need your provider's terms. Sume STT is a hosted job: you send an audio_url and Sume returns word timings. It uses ElevenLabs Scribe v2 behind the endpoint at a provider list price of $0.008 a minute, and Sume charges about $0.01 a minute after its 1.25 margin. See the API reference for the request body.

Steps to add attribution cleanly

• Open the model page and copy the exact attribution wording the author asks for.
• Add it to your third-party notices file.
• Ship the licence text next to the model weights.
• Re-check the page at each model update; terms can change.

Common mistakes

Teams often treat the licence as an afterthought and discover the notice requirement when a release is already in review. Put the notice in the build checklist on day one. A second mistake is assuming that permissive terms on one release carry to the next; a new version can ship with different terms, so keep a copy of the page you relied on, with its date.

A third mistake is to confuse the model licence with the data licence. The audio your users record, and the transcripts it produces, belong to your own terms with them. Nothing in this post changes that, and none of it is legal advice.

What Sume does not do

Sume does not give licence advice, and it does not host Phonon-2. Sume STT is one hosted endpoint with no on-device mode. If your product must work offline, the hosted job is not an answer. Compare the two paths in Phonon-2 or hosted Sume STT, and test accuracy on your own audio first.