I don't think many of the list subscribers are lawyers. This is a
developer list, after all, so perhaps this is not the most reliable
place to get legal advice.
But I think what Paul is saying is the sensible thing: if the GPL
plugin is integral to the host functionality and loaded automatically,
any developer advising a jury will concur that the situation is in no
significant way different to dynamic linking at compile time. The host
is indeed a derivative work and thus should not be _distributed_
without providing its source code. You can use it in the machine you
have developed it, though, or in any other one as long as you copy
both the plugin and the host source code to it.
I guess if the host authors are bent on not contributing to the OSS
community with their source code, they could always try to contact the
plugin authors and get from them a proprietary license, which they are
entitled to provide as their copyright holders.
For instance, let's say someone writes an automatic accompaniment
generator and uses internally a GPL sampler to play it and render a
WAV version. I'd say that's derivative, since those features
contribute significantly to the product usefulness, and thus its
marketability. IANAL, but if I was asked by a jury that would be my
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