Yes
Both The Unlicense and zlib License are permissive licenses with minimal obligations. Combining code under them is straightforward; ensure the original copyright notices are preserved alongside any new ones.
| License | Family | Patent grant |
|---|---|---|
| The Unlicense (Unlicense) | permissive | No (implicit at most) |
| zlib License (Zlib) | permissive | No (implicit at most) |
The Unlicense: Public-domain dedication with a fallback license for jurisdictions that don't recognise PD.
zlib License: Permissive, with a misrepresentation-of-origin clause.
If you found this page because you're trying to figure out whether shipping a particular dependency is safe, the answer above is a starting point — not a substitute for reading the actual licenses or talking to a lawyer when stakes are high.
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