Arnoud Engelfreit wrote: > The FSF seems to believe such a clause is incompatible with the GPL.
I've got to admit that is a strong argument against it. But couldn't the same argument be made against any patent-defence clause? > Generally speaking, the clause seems unreasonably broad, since > if I get software from you, why should you be allowed to tell > me I cannot sue someone you've never heard of? I don't see it as being unreasonable. A patent-based attack on an open source project hurts all open source projects. Furthermore the assumption that I should automatically know about any software patent before I start implementing seems pretty unreasonable to me. "If we do not hang together we shall assuredly hang seperately" > The only alternative left is to say "We have software patents we > might want to enforce, so we cannot use Apache-licensed stuff." The clause only prevents them from enforcing these rights against open source software, which is what we want. Large companies routinely implement cross-licensing agreements; non-agression pacts under which they promise not to sue each other for patent licenses. Mutual patent defence clauses apply this principle to open source. There may be a "protect it or lose it" principle in patent law, such that if a patent holder fails to sue an open source project that violates a patent then the patent becomes unenforceable against other parties. If so then perhaps the clause could say that patent holders who use Apache-licensed software automatically grant a free non-exclusive license to all their patents to all OSS licensed software, and the patent license can be revoked by ceasing to use the Apache-licensed package and destroying all copies. This has a similar effect to the mutual defence clause, but the patent-holder can get the patent back at any time and in the mean time does not lose the right to sue other violators. It also has the effect of making the license GPL-compatible, since it is never withdrawn. In another email Brian Behlendorf writes: > imagine someone who wants to cause harm to a patent-holder releasing a > library that implements their patent as open-source-licensed software. OK, so what if they do? If the library is useful then its just another useful piece of OSS, and the motives of the author are irrelevant. If it is not useful then the attack on the patent holder fails because it makes no difference to their income. The only way I can see such an attack being useful is if the would-be violator releases just enough of their source code as OSS to escape the patent whilst keeping the rest of their package wrapped up in secrecy. This can be solved by phrasing the patent-license-grant clause to not cover anyone who incorporates OSS (from whatever source) in a closed-source package. They can negotiate for licenses like anyone else. Paul.
