# Muse Spark Open license: can you use it commercially?

Canonical: https://theagenticweekly.com/guides/muse-spark-open-license · Last verified: 2026-10-27 · Published: 2026-10-27 · Author: Agentic Weekly (operated independently from Texas, US) · Versions covered: Muse Model License, version Muse Spark Open, release date October 15, 2026, read on its Hugging Face page 2026-10-27 · Evidence: Reported (license text read from Meta's Hugging Face model page; not legal advice; nothing run by us) · Tools: 

Checked 2026-10-27 by Agentic Weekly's editorial process: vendor pages re-read.

> Yes, with conditions. As of 2026-10-27 (America/Chicago), Meta's Muse Model License for Muse Spark Open allows use, fine-tuning, distillation, distribution and sale. It requires the notice "Built with Muse Spark Open", and a separate written agreement with Meta to offer it as an API service if your group's revenue exceeds $20 million in any 12 months. Not legal advice.

## What the license lets you do

The license text on Meta's [Hugging Face page](https://huggingface.co/meta-models/Muse-Spark-Open-816B-A42B) grants permission, free of charge, to "use, copy, modify (including fine-tune), create derivative works, distill, merge, publish, distribute, sublicense, and/or sell copies of the Software", in each case subject to its conditions. "Software" covers the model, code, weights, parameters, configuration files and documentation. The page is gated, so you must log in to Hugging Face and accept the conditions to download the files; the license text itself was visible to us.

Table: Muse Model License (version Muse Spark Open, release date October 15, 2026): what each clause says, summarized by us

| Question | Answer from the license text | Clause |
|---|---|---|
| Can I use it commercially? | Yes, subject to the conditions below; selling copies is expressly permitted | Grant |
| Can I fine-tune or distill it? | Yes; results are called Derivatives, and the conditions travel with them | Grant and clause 2 |
| Do I have to keep the license with copies? | Yes: include the copyright notice, the license and the Usage Policy in all copies or substantial portions of the Software and Derivatives | Clause 1 |
| Do I have to credit Meta? | Yes: prominently display "Built with Muse Spark Open" in the user interface of each product or service that uses the Software or Derivatives, or in the documentation, website or settings menu | Clause 2 |
| Can I offer it as an API to others? | Only freely below the revenue threshold; above $20 million aggregate gross revenue for you and your affiliates in any consecutive 12 months, you must notify Meta and sign a separate written agreement first | Clause 3 |
| Does the API rule apply to my own product? | No: clause 3 does not apply to internal use, research, any commercial activity that is not Model as a Service, or using it as a component to power features of your own product that is not itself Model as a Service | Clause 3(a) and (b) |
| Who owns the outputs? | Meta claims no ownership of outputs | Clause 4 |
| Is there a warranty? | No: provided "AS IS"; Meta has no liability for Derivatives and you are solely responsible for their safety, deployment and use | Clause 5 |

## The Model-as-a-Service clause in plain terms

Clause 3 defines Model as a Service as providing a third party with access to AI models "as a product or service, via API or a similar interface, where the third party receives outputs of such models." The separate-agreement requirement applies only if the aggregate gross revenue of the licensee and its affiliates exceeds twenty million US dollars (or the equivalent in other currencies) during any consecutive twelve-month period. We read that as: a small company can host the model as an API without a separate agreement, and a large company cannot, but a lawyer should confirm how it applies to you.

## The Usage Policy

The license incorporates a Usage Policy (Exhibit A, dated October 15, 2026). It says Muse Spark Open "is not intended for individuals under the age of 18" and lists prohibited uses, including breaking the law, harassment, unlicensed professional practice, malware, circumventing safety measures, certain military and weapons uses, and deceiving or impersonating people. Read the full policy at the source before you ship; we do not reproduce it.

## Is it open source?

The Hugging Face page lists the license as "muse-model-license" and the model's weights are available to download after accepting conditions. We make no claim that the license meets the Open Source Initiative definition. The conditions above, including the notice, the Usage Policy and the API carve-out, are why we call it open weights under a custom license and not an open-source license.

## What we tested

We read the license text on 2026-10-27 and did not run the model or consult a lawyer. Section summaries and the table are ours; quoted phrases are Meta's. This is not legal advice. For the model's specifications and benchmark rows, see [Muse Spark Open](https://theagenticweekly.com/models/muse-spark-open).

## FAQ

### Can I use Muse Spark Open commercially?

Yes under the Muse Model License conditions: keep the license and Usage Policy with copies, display "Built with Muse Spark Open", and get a separate written agreement with Meta before offering it as an API service if your group's revenue exceeds $20 million in any 12 months.

### Do I have to credit Meta when I use Muse Spark Open?

Yes. Clause 2 requires you to prominently display "Built with Muse Spark Open" in the user interface of each product or service that uses the model or Derivatives, or in the accompanying documentation, website or settings menu.

### When do I need a separate agreement with Meta?

When you or your affiliates offer Muse Spark Open or its Derivatives to third parties as a Model as a Service (an API where they receive outputs) and your aggregate gross revenue exceeds $20 million in any consecutive 12 months.

### Is Muse Spark Open open source?

Meta publishes the weights under its custom Muse Model License. We make no claim that it meets the Open Source Initiative definition, because the license adds a notice requirement, a Usage Policy and a revenue-based API condition.

### Is this legal advice?

No. This page summarizes the license text read on 2026-10-27 and quotes short phrases from it. It is not legal advice, and you should have a lawyer review the full license and Usage Policy before relying on it.

### Have you tested Muse Spark Open?

No. We did not download or run the model. This guide summarizes the license text and Usage Policy as read on 2026-10-27 and quotes short phrases from them, so it says nothing about quality, speed or behaviour.

## Sources

- [Hugging Face: Muse-Spark-Open-816B-A42B (Muse Model License and Usage Policy)](https://huggingface.co/meta-models/Muse-Spark-Open-816B-A42B) (fetched 2026-10-27)

## Related

- [Muse Spark Open](https://theagenticweekly.com/models/muse-spark-open)
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- [Upcoming AI model dates](https://theagenticweekly.com/models/upcoming)

## Changelog

- 2026-10-27: First published from the license text on Meta's Hugging Face model page, read on this date. Not legal advice.

## How to cite

Agentic Weekly, "Muse Spark Open license: can you use it commercially?", last updated 2026-10-27, https://theagenticweekly.com/guides/muse-spark-open-license