Research report 03 / Release momentum
Open Model Momentum
Verified open and disclosed-license model releases, developer activity, and release cadence.
Public editionLive dataset
- Open releases
- 4
11 total model launches
- Developers
- 4
Named release organizations
- Most active
- Anthropic
1 releases
- Open share
- 36%
Disclosed open availability/license
Data status4 verified records across 2 periods
The periods are real, but no series repeats yet. Points are shown without a trend line to avoid implying continuity.
Verified observationHover or focus any mark for exact valuesData and chart downloads share this dataset
Coverage note
This first edition measures release momentum. Historical download and like growth cannot be inferred before periodic snapshots are collected.
- Dataset ID
- spd:open-model-momentum
- Coverage
- 2026-06/2026-08-18
- Records
- 4
- Fields
- 6
- Formats
- CSV / JSON
- Updated
| Date | Model | Developer | Release type | Availability | License |
|---|---|---|---|---|---|
| 2026-06-09 | Claude Fable 5 | Anthropic | Public release (Mythos-class); available via API and Enterprise | Publicly accessible via API and Enterprise; included in subscription plans through 2026-06-22 after which access requires purchase of usage credits; some sensitive-topic access restricted and Mythos 5 limited to vetted Project Glasswing participants | — |
| 2026-08-10 | Muse Glimmer | Meta | open weights | Consumer hardware with 24 GB or 32 GB of memory | Apache 2.0 |
| 2026-08-11 | Nemotron 3.5 Lightning | Nvidia | open weights (public release) | Available through Nvidia and model repositories including Hugging Face and ModelScope; NeMo Switchyard available on GitHub | OpenMDW-1.1 |
| 2026-08-18 | GPT-5.6 Sol | OpenAI | API | Limited release to a small group of customers; wider access planned later | — |
Methodology
How to read this report
- 01Open status requires an explicit open, community, or named open license/availability disclosure.
- 02Momentum currently measures verified release cadence; download-growth snapshots will be added prospectively rather than reconstructed.
- 03A model without disclosed licensing is excluded from the open series.
Sources
Evidence
9 publishers supporting 12 records. Expand a publisher to inspect its cited pages.