Two models can both be marketed as “open” and have completely different rules about what you’re actually allowed to do with them. Reading the license takes ten minutes and saves real headaches later.
Apache 2.0 and MIT are the gold standard for permissiveness: download, modify, deploy commercially, no royalty, no obligation to share changes back. When a model ships under one of these, “open” is accurate in the fullest sense.
Many releases use custom licenses with conditions that don’t show up in the headline: usage caps tied to company size, restrictions on training a competing model, geographic limits on commercial deployment. None of this makes a model less useful for research, but it matters enormously if you’re building a commercial product on top of it.
Before building on one, check: does the license permit commercial use at your company’s actual scale? Are there geographic restrictions? Does using the model’s outputs to train another model violate the terms? Is there an obligation to share modifications back?
“Open” is a marketing word with a wide range of actual legal meanings, the same nuance covered in our explainer on open-weight versus open-source. Read the specific license text before building a real product on it. Browse current models and their licenses directly at Hugging Face.




