If patent rights are required to call it free, BSD and MIT aren't that great either. Apache 2.0 explicitly grants patent rights, CC0 explicitly calls out that it doesn't, BSD and MIT are simply silent on the issue since they were written in a time before the issue became relevant. The silence allows people to argue that they contain an implicit patent grant. An argument that has merit in the US, but not in every jurisdiction out there.
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If patent rights are required to call it free, BSD and MIT aren't that great either. Apache 2.0 explicitly grants patent rights, CC0 explicitly calls out that it doesn't, BSD and MIT are simply silent on the issue since they were written in a time before the issue became relevant. The silence allows people to argue that they contain an implicit patent grant. An argument that has merit in the US, but not in every jurisdiction out there.