A service, not a shaming
Some of the most beloved repositories in AI are not open source — and most coverage never mentions it. A public GitHub repo, a free tier, or a downloadable model does not make something open source. The license does. Here are the projects most often mislabeled, with the exact terms that disqualify them, so you can decide with your eyes open.
None of this is a knock on the software. Much of it is excellent, and generous for most users. The point is precision: if you build a business on a license, read the license.
Proprietary (all rights reserved; Anthropic Commercial Terms)
It practically defined the agentic-coding-CLI category, and its public GitHub repo leads many to assume it's open source. It is not: the LICENSE.md reserves all rights under Anthropic's Commercial Terms of Service. The repo hosts installers, docs, and the issue tracker; the tool itself ships as a distributed bundle.
Custom personal-use-only license (not OSI)
One of GitHub's most-starred repositories ever, and a common example of 'famous but not open source.' Its custom license permits personal use only: you can't republish the content in blogs or newsletters without consent, and commercial reuse is prohibited. (And despite appearances it isn't a fork — the author renamed his account from kamranahmedse to nilbuild.)
Apache-2.0 with additional conditions (source-available, not OSI)
Hugely popular and routinely labeled 'Apache 2.0' — but it's Apache 2.0 with additional conditions, and those conditions (no multi-tenant operation without authorization; no removing the Dify logo or copyright) impose field-of-use restrictions that fail the Open Source Definition.
Sustainable Use License + n8n Enterprise License (fair-code, not OSI)
Enormously popular and constantly described as open source — but n8n itself uses the term 'fair-code', not open source. The Sustainable Use License limits use to your own internal business, non-commercial, or personal purposes, and forbids hosting n8n as a commercial service.
Open WebUI License (custom, BSD-3-based + branding clause)
The highest-profile relicensing in local AI. It moved from permissive terms to a custom license that forbids removing the 'Open WebUI' branding unless you have 50 or fewer users in a rolling 30-day window (or written permission). That branding-protection clause is a use restriction OSI licenses don't allow.
CC BY-NC-ND-4.0 (not OSI; no commercial use, no derivatives)
Gorgeous and widely shared, but licensed CC BY-NC-ND: no commercial use and no derivatives. Despite the open-repo optics it's among the most restrictive licenses in this catalog, and it doubles as marketing for a paid newsletter.
These are genuinely open on the software side, but the model weights ship under custom or non-commercial terms. Featured in the catalog with an amber badge — listed here so the distinction is easy to find.
MIT code, but weights are described as research-oriented; commercial use is directed to Microsoft
DeepSeek Model License (commercial OK; use restrictions in Attachment A)
Mixed: klein 4B + autoencoder Apache-2.0; klein 9B and dev 32B under the FLUX Non-Commercial License
LTX-2 Community License — freely downloadable, commercial use for smaller entities, company-scale restrictions apply
OpenMDW-1.1
SAM License (Meta custom): commercial use permitted, acceptable-use restrictions, gated download
Think we've mislabeled something, or missed a repo people keep calling open source? The tally stays honest through corrections.
How verification works →