Meanwhile, there was disagreement even among copyleft enthusiasts about the

importance of the provision.  A coalition never formed, and ultimately the

more powerful interest implicitly allied with the companies who deeply opposed

the Affero clause such that the FSF felt the Affero clause would need its own

license, but one compatible with GPLv3. 

GPLv3~\S13 makes GPLv3 compatible with the AGPLv3, so that at least code can

be shared between AGPLv3'd and GPLv3' projects, even if the Affero clause

does not automatically apply to all GPLv3'd works.

%FIXME-LATER:  no time to do this justice, will come back later, instead the

%above.

%% Some of this hostility seemed to be based on a misapprehension that

%% Affero-like terms placed on part of a covered work would somehow extend

%% to the whole of the work.\footnote{It is possible that the presence of

%% the GPLv2-derived copyleft clause in the existing Affero GPL contributed

%% to this misunderstanding.}  Our explanations to the contrary did little

%% to satisfy these critics; their objections to 7b4 instead evolved into a

%% broader indictment of the additional requirements scheme of section 7.

%% It was clear, however, that much of the concern about 7b4 stemmed from

%% its general formulation.  Many were alarmed at the prospect of GPLv3

%% compatibility for numerous Affero-like licensing conditions,

%% unpredictable in their details but potentially having significant

%% commercial consequences.

%% On the other hand, many developers, otherwise sympathetic to the policy

%% goals of the Affero GPL, have objected to the form of the additional

%% requirement in that license.  These developers were generally

%% disappointed with our decision to allow Affero-like terms through

%% section 7, rather than adopt a condition for GPLv3.  Echoing their

%% concerns about the Affero GPL itself, they found fault with the wording

%% of the section 7 clause in both of the earlier drafts.  We drafted 7b4

%% at a higher level than its Draft 1 counterpart based in part on comments

%% from these developers. They considered the Draft 1 clause too closely

%% tied to the Affero mechanism of preserving functioning facilities for

%% downloading source, which they found too restrictive of the right of

%% modification.  The 7b4 rewording did not satisfy them, however. They

%% objected to its limitation to terms requiring compliance by network

%% transmission of source, and to the technically imprecise or inaccurate

%% use of the phrase ``same network session.''

%% We have concluded that any redrafting of the 7b4 clause would fail to

%% satisfy the concerns of both sets of its critics.  The first group

%% maintains that GPLv3 should do nothing about the problem of public

%% use. The second group would prefer for GPLv3 itself to have an

%% Affero-like condition, but that seems to us too drastic. By permitting

%% GPLv3-covered code to be linked with code covered by version 2 of the

%% Affero GPL, the new section 13 honors our original commitment to

%% achieving GPL compatibility for the Affero license.

%% Version 2 of the Affero GPL is not yet published.  We will work with

%% Affero, Inc., and with all other interested members of our community, to

%% complete the drafting of this license following the release of Draft 3,

%% with a goal of having a final version available by the time of our

%% adoption of the final version of GPLv3.  We hope the new Affero license

%% will satisfy those developers who are concerned about the issue of

%% public use of unconveyed versions but who have concerns about the

%% narrowness of the condition in the existing Affero license.

%% As the second sentence in section 13 indicates, when a combined work is

%% made by linking GPLv3-covered code with Affero-covered code, the

%% copyleft on one part will not extend to the other part.\footnote{The

%% plan is that the additional requirement of the new Affero license will

%% state a reciprocal limitation.} That is to say, in such combinations,

%% the Affero requirement will apply only to the part that was brought into

%% the combination under the Affero license.  Those who receive such a

%% combination and do not wish to use code under the Affero requirement may

%% remove the Affero-covered portion of the combination.

Meanwhile, those who criticize the permission to link with code under the Affero

GPL should recognize that most other free software licenses also permit

such linking. 

\section{GPLv3~\S14: So, When's GPLv4?}

\label{GPLv3s14}

No substantive change has been made in section 14. The wording of the section

has been revised slightly to make it clearer.

It's unclear when the FSF might consider publishing GPLv4.  However, this

section makes it clear that the FSF is the sole authority who can decide

such.

The main addition to this section allows a third-party proxy to be appointed

by contributors who wish someone else to make relicensing to new versions of

GPL when they are released.  This is a ``halfway'' point between using ``-only''

or ``-or-later'' by consolidating the decision-making on that issue to a

single authority.

% FIXME-LATER: better proxy description

\section{GPLv3~\S15--17: Warranty Disclaimers and Liability Limitation}

No substantive changes have been made in sections 15 and 16.

% FIXME: Section header needed here about choice of law.

% FIXME: reword into tutorial

Some have asked us to address the difficulties of internationalization

by including, or permitting the inclusion of, a choice of law

provision.  We maintain that this is the wrong approach.  Free

software licenses should not contain choice of law clauses, for both

legal and pragmatic reasons.  Choice of law clauses are creatures of

contract, but the substantive rights granted by the GPL are defined

under applicable local copyright law. Contractual free software

licenses can operate only to diminish these rights.  Choice of law

clauses also raise complex questions of interpretation when works of

software are created by combination and extension.  There is also the

real danger that a choice of law clause will specify a jurisdiction

that is hostile to free software principles.

% FIXME: reword into tutorial, \ref to section 7.

Our revised version of section 7 makes explicit our view that the

inclusion of a choice of law clause by a licensee is the imposition of

an additional requirement in violation of the GPL.  Moreover, if a

program author or copyright holder purports to supplement the GPL with

a choice of law clause, section 7 now permits any licensee to remove

that clause.

% FIXME: does this need to be a section, describing how it was out then in

% then out then in? :)

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

\chapter{The Lesser GPL}

As we have seen in our consideration of the GPL, its text is specifically

designed to cover all possible derivative works under copyright law. Our

goal in designing GPL was to make sure that any derivative work of GPL'd

software was itself released under GPL when distributed. Reaching as far

as copyright law will allow is the most direct way to reach that goal.

However, while the strategic goal is to bring as much Free Software

into the world as possible, particular tactical considerations

regarding software freedom dictate different means. Extending the

copyleft effect as far as copyright law allows is not always the most

prudent course in reaching the goal. In particular situations, even

those of us with the goal of building a world where all published

software is Free Software realize that full copyleft does not best

serve us. The GNU Lesser General Public License (``GNU LGPL'') was

designed as a solution for such situations.

\section{The First LGPL'd Program}

The first example that FSF encountered where such altered tactics were

needed was when work began on the GNU C Library. The GNU C Library would

become (and today, now is) a drop-in replacement for existing C libraries.

On a Unix-like operating system, C is the lingua franca and the C library

is an essential component for all programs. It is extremely difficult to

construct a program that will run with ease on a Unix-like operating

system without making use of services provided by the C library --- even

if the program is written in a language other than C\@. Effectively, all

user application programs that run on any modern Unix-like system must

make use of the C library.

By the time work began on the GNU implementation of the C libraries, there

were already many C libraries in existence from a variety of vendors.

Every proprietary Unix vendor had one, and many third parties produced

smaller versions for special purpose use. However, our goal was to create

a C library that would provide equivalent functionality to these other C

libraries on a Free Software operating system (which in fact happens today

on modern GNU/Linux systems, which all use the GNU C Library).

Unlike existing GNU application software, however, the licensing

implications of releasing the GNU C Library (``glibc'') under GPL were

somewhat different. Applications released under GPL would never

themselves become part of proprietary software. However, if glibc were

released under GPL, it would require that any application distributed for

the GNU/Linux platform be released under GPL\@.

Since all applications on a Unix-like system depend on the C library, it

means that they must link with that library to function on the system. In

other words, all applications running on a Unix-like system must be

combined with the C library to form a new whole derivative work that is

composed of the original application and the C library. Thus, if glibc

were GPL'd, each and every application distributed for use on GNU/Linux

would also need to be GPL'd, since to even function, such applications

would need to be combined into larger derivative works by linking with

glibc.

At first glance, such an outcome seems like a windfall for Free Software

advocates, since it stops all proprietary software development on

GNU/Linux systems. However, the outcome is a bit more subtle. In a world

where many C libraries already exist, many of which could easily be ported

to GNU/Linux, a GPL'd glibc would be unlikely to succeed. Proprietary

vendors would see the excellent opportunity to license their C libraries

to anyone who wished to write proprietary software for GNU/Linux systems.

The de-facto standard for the C library on GNU/Linux would likely be not

glibc, but the most popular proprietary one.

Meanwhile, the actual goal of releasing glibc under GPL --- to ensure no

proprietary applications on GNU/Linux --- would be unattainable in this

scenario. Furthermore, users of those proprietary applications would also

be users of a proprietary C library, not the Free glibc.

The Lesser GPL was initially conceived to handle this scenario. It was

clear that the existence of proprietary applications for GNU/Linux was

inevitable. Since there were so many C libraries already in existence, a

new one under GPL would not stop that tide. However, if the new C library

were released under a license that permitted proprietary applications

to link with it, but made sure that the library itself remained Free,

an ancillary goal could be met. Users of proprietary applications, while

they would not have the freedom to copy, share, modify and redistribute

the application itself, would have the freedom to do so with respect to

the C library.

There was no way the license of glibc could stop or even slow the creation

of proprietary applications on GNU/Linux. However, loosening the

restrictions on the licensing of glibc ensured that nearly all proprietary

applications at least used a Free C library rather than a proprietary one.

This trade-off is central to the reasoning behind the LGPL\@.

Of course, many people who use the LGPL today are not thinking in these

terms. In fact, they are often choosing the LGPL because they are looking

for a ``compromise'' between the GPL and the X11-style liberal licensing.

However, understanding FSF's reasoning behind the creation of the LGPL is

helpful when studying the license.