Yes
Both The Unlicense and ISC 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) |
| ISC License (ISC) | permissive | No (implicit at most) |
The Unlicense: Public-domain dedication with a fallback license for jurisdictions that don't recognise PD.
ISC License: Functionally equivalent to MIT; Internet Systems Consortium's house license.
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.
LicenseHound walks every transitive dependency in your repo, maps each to its SPDX license, and flags pairs like this one in PR comments. The CLI is free; the team dashboard is paid.