[License-review] Approval: BSD + Patent License

[John Cowan]

Jim Wright scripsit:

>  - The UPL expressly permits sublicensing, the BSD+PL does not  [...]
>  such that under the BSD+PL you could not necessarily, e.g., cut
>  and paste code into something licensed under terms that require the
>  entirety of the work to be under a single license, or offer the work
>  on proprietary terms, and purporting to do so could be infringing.

Traditionally, neither of these has been seen as an issue with the
BSD licenses.  Because they grant licenses directly from the named
contributor(s) to whoever has the source code, there is no need to derive
one's license through a sublicensor: it is original.  (This is also why
the BSD licenses don't explicitly grant access to the source code: they
*presume* that you have the source code in hand.)  This is a consequence
of open source licenses being public licenses, meaning that everyone is
a licensee.

The GNU GPL and similar licenses require that a composite work containing
any GPLed code be licensed *as a whole* under the relevant flavor of
copyleft license, but they do not and cannot require that *no part*
of the code be licensed under any other license (the term "entirety" is
somewhat ambiguous here).  If you receive a work in source form under,
say, the GPLv2, then you have a GPLv2 license to the whole work, but any
BSD snippets in it are *also* licensed to you on BSD terms directly by
the BSD licensor, and you can extract them and use them in BSD-ish ways.
This is the principle by which an anthology, for example, that contains
public domain short stories (I have such a thing on my desk at present),
cannot change the fact that stories embedded in it which are in the
public domain are still in the public domain, and I can copy them out
of the book (assuming they have not been modified by the anthologist).

For the typical case of BSD snippet reuse in proprietary works, the
same thing applies in principle, but you cannot typically extract the
snippet from the binary because most proprietary licenses forbid reverse
engineering, so your BSD license to them is not very useful.

-- 
John Cowan          http://www.ccil.org/~cowan        cowan at ccil.org
The experiences of the past show that there has always been a discrepancy
between plans and performance.        --Emperor Hirohito, August 1945