xref: /netbsd-src/external/gpl3/README (revision a9374b6b8772c2a7447266163271e0dc795a0e3e)
1*a9374b6bSreed$NetBSD: README,v 1.1 2010/04/01 14:13:25 reed Exp $
2*a9374b6bSreed
3*a9374b6bSreedThe code within the src/external/gplv3 directories may have serious
4*a9374b6bSreedlegal impacts if you are a company and redistributing or changing
5*a9374b6bSreedthis code (as a company holding patents). We recommend you contact
6*a9374b6bSreedyour lawyer before using it.
7*a9374b6bSreed
8*a9374b6bSreedPlease do not import new GPLv3 projects without Board approval.
9*a9374b6bSreed
10*a9374b6bSreed--------------------------------------------------------------------
11*a9374b6bSreed
12*a9374b6bSreedStatement for The NetBSD Foundation's Position on the GPLv3
13*a9374b6bSreed
14*a9374b6bSreedNetBSD provides source code with the goal for anyone to be able
15*a9374b6bSreedto use it for whatever they want, as long as they follow the simple
16*a9374b6bSreedlicensing terms. Historically, most of the original code used
17*a9374b6bSreedBerkeley-style licensing and NetBSD's own code uses a simple
18*a9374b6bSreedtwo-clause Berkeley-style license. To summarize: modifications are
19*a9374b6bSreedallowed, the source code may be redistributed and the binaries (or
20*a9374b6bSreedexecutables) may be distributed as long as the copyright and
21*a9374b6bSreeddisclaimer is included.  NetBSD's code may be extended and sold
22*a9374b6bSreedwithout sharing back the source code changes.
23*a9374b6bSreed
24*a9374b6bSreedNetBSD also uses and redistributes source code and binaries from
25*a9374b6bSreedsource code obtained from external third parties. This source code
26*a9374b6bSreedis segregated by placing it in the src/external and sys/src/external
27*a9374b6bSreeddirectories which are categorized per license. Examples of this
28*a9374b6bSreedinclude:  ISC BIND, Solaris ZFS, CVS, GNU Binutils, Postfix, X.org
29*a9374b6bSreedX Windowing System, and other software that are primarily maintained
30*a9374b6bSreedoutside of NetBSD.
31*a9374b6bSreed
32*a9374b6bSreedIn some cases, the third-party software is licensed under terms
33*a9374b6bSreedthat conflict with NetBSD's own goals. For example, the GPLv2 is
34*a9374b6bSreeda "copyleft" license  -- it requires that anyone who distributes
35*a9374b6bSreedexecutable or object code based on the source code, also make the
36*a9374b6bSreedsource code and modifications available to the public.  (NetBSD's
37*a9374b6bSreedown code doesn't require companies to share their changes.)
38*a9374b6bSreed
39*a9374b6bSreedThe GPLv3 (GNU General Public License Version 3) includes clauses
40*a9374b6bSreedthat may cause additional burdens to developers or companies who
41*a9374b6bSreedmay modify the source code or ship products based on the source
42*a9374b6bSreedcode. The following summarizes some of these issues:
43*a9374b6bSreed
44*a9374b6bSreed- The license allows the user to circumvent measures preventing
45*a9374b6bSreedsoftware changes (#3).  This is known as the Tivoization clause.
46*a9374b6bSreedIn addition, this same clause is an anti-DRM, anti-DMCA clause --
47*a9374b6bSreedas the developer allows the end-user to attempt to circumvent or
48*a9374b6bSreedbreak the technological protection measures. Also, any information
49*a9374b6bSreedor authorization keys required to install or run modified versions
50*a9374b6bSreedmust also be provided (#6).
51*a9374b6bSreed
52*a9374b6bSreed- The patent clause (#11) says the copyright holders grant a
53*a9374b6bSreednon-exclusive, worldwide, royalty-free patent license.  You may be
54*a9374b6bSreedrequired to extend the royalty-free patent license(s) to all
55*a9374b6bSreedrecipients or future users and developers who use the code.  In
56*a9374b6bSreedaddition, you may not initiate litigation for a patent infringement
57*a9374b6bSreed(#10).
58*a9374b6bSreed
59*a9374b6bSreedWe recommend companies redistributing GPLv3 licensed code to
60*a9374b6bSreedconsult their lawyer before using it.
61*a9374b6bSreed
62*a9374b6bSreedIt is the intent of the NetBSD project to use as little GPL licensed
63*a9374b6bSreedsoftware as possible to provide maximum freedom for development
64*a9374b6bSreedand distribution of NetBSD derived products.
65*a9374b6bSreed
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