Use the Blue Oak Model License

a new state-of-the-art permissive license

March 6, 2019

The Blue Oak Model License 1.0.0 is the new state-of-the-art permissive public license for software. Consider it for your next release.

Blue Oak is easier to read, and more legally complete, than MIT, BSD, or ISC. It’s shorter, simpler, and more permissive than Apache 2.0. It avoids the legal confusion of Unlicense, Fair, and 0BSD.

The Blue Oak Model License grew out of the license list. We compiled the list not to apply a new definition of “permissive license”, or to expound any theory or philosophy of licensing, but to create a useful, reusable component of contracts, policies, and grants to guide those who can’t find or afford a professional license navigator. We rated licenses by asking where they belong, practically, and polling the judgment of contributing lawyers.

Naturally, patterns began to emerge. Licenses with explicit patent grants, like BSD-2-Clause Plus Patent, rose to the top. Licenses without, like MIT and BSD, dropped toward the bottom. Licenses with multiple, administratively complex attribution conditions sunk. As did licenses lacking statements of irrevocability, licenses with defensive termination provisions or unclear patent scopes, licenses that beg contract-or-license confusion, and licenses that fail to anticipate contributions from others.

Those characteristics became unspoken guidelines. Those guidelines became a checklist. That checklist became a specification. As an exercise, that specification became a license. Finding no other form meeting all its requirements, that exercise became the Blue Oak Model License.

We’re particularly proud of a few specific features:

Language Simplified

The model license was written to be read and applied by hackers and lawyers alike. It’s only about 240 words. Less than many pop songs.

Permission Clarified

The model license grants explicit copyright and patent permission. Copyright permission covers all contributions. Patent permission covers all patents reading on the software, now or later.

Contribution Expected

The model license covers all contributions to the project, in the same terms. This feature does double duty. First, it reassures users that they have permission from all contributors. Second, it expresses the expectation that new contributors will make their work available in the same way.

Attribution Demined

The model license adds an automatic excuse, or cure provision, for failures to follow the rule about providing notice of the license terms, often called “attribution”. We have seen this for copyleft rules in the past, such as under the GPL Cooperation Commitment and GPLv3. We see latent risk of claims for failure to provide attribution. The Blue Oak Model License paves a path to compliance, rather than to court.

Uncertainty Avoided

The model license takes assertive steps to head off legal uncertainty about the legal treatment of its terms. Most common licenses don’t address whether they’re bare licenses, contract terms, or both. That leads to uncertainty about what contributors can sue for when their terms aren’t respected, and about whether they can revoke their licenses.