commercial software that restricts freedom (such as nearly all of

Microsoft's and Oracle's offerings).

and ``free software'' are known to be trademarked or otherwise legally

restricted by any organization in

any jurisdiction.  As such, it's quite common that these terms are abused and

modify and change the software.  This means that companies have a right to

hire anyone they wish to modify their Free Software.  Additionally, such

companies may contract with other companies to commission software

\subsection{The Freedom to Copy and Share}

respect software freedom, therefore, permit altruistic sharing of software

among friends.

includes selling copies of Free Software: that is, Free Software can

be distributed for any monetary

price to anyone.  Those who redistribute Free Software commercially also have

\subsection{The Freedom to Share Improvements}

The freedom to modify and improve is somewhat empty without the freedom to

pillar of altruistic sharing of improved Free Software. Historically

it was typical for a

Free Software project to sprout a mailing list where improvements

``subroutine'' that could be reused not just for all FSF-copyrighted

programs, but also by anyone else.  As the FSF claimed in its announcement of

the GPLv1\footnote{The announcement of GPLv1 was published in the

    number 6 dated January 1989}.  (Thanks very much to Andy Tai for his

  \href{http://www.free-soft.org/gpl_history/}{consolidation of research on

    the history of the pre-v1 GPL's}.)}:

\item GPLv2~\S3 includes more detailed requirements, including the phrase

 ``the scripts used to control compilation and installation of the

  \S~\ref{GPLv2s3} in this tutorial).

\end{itemize}

as the Creative Commons ``Share Alike'' licenses, the Eclipse Public License

and the Mozilla Public License \textbf{require} all copyright holders choosing

to use any version of those licenses to automatically accept and relicense

Eclipse Foundation, and the Mozilla Foundation (like the FSF) have generally

served as excellent stewards of their licenses.  Copyright holders using

those licenses seems to find it acceptable to fully delegate all future

\medskip

not attempting to cover them.  Furthermore, the GPLv2 ensures the freedom

to run specifically by stating the following:

\begin{quote}

  \item Computer manufacturers'

design standards

\end{itemize}

For many, this is where the ``magic'' happens that defends software

freedom upon redistribution.  GPLv2~\S2 is the only place in GPLv2

that governs the modification controls of copyright law.  If users

those changes.  Thus, this sections ensures that the body of GPL'd software, as it

continues and develops, remains Free as in freedom.

GPLv2~\S2(b) further states that the software must ``be licensed \ldots to all

third parties.''  This too yields some confusion, and feeds the

available to the public at large.  However, the text here does not say

that.  Instead, it says that the licensing under terms of the GPL must

extend to anyone who might, through the distribution chain, receive a copy

along the distribution chain must have the right to get the source and

exercise those freedoms that require it.

distribute binary software commercially.  Without GPLv2~\S3(c), that benefit

would be at the detriment of the companies' customers; the burden of

source code provision would be unfairly shifted to the companies'

stop distributing the GPLv2'd version (assuming GPLv2~\S3(b) was never used),

but they may not revoke the rights under GPLv2 already granted.

GPL'd software, it is because of their \emph{own actions}, not that of the

copyright holder.  The copyright holder does not decide when GPLv2~\S4

termination occurs (if ever); rather, the actions of the licensee determine

holder.  Both are common practice, although

\tutorialpartsplit{as discussed in \textit{A Practical Guide to GPL

    Compliance}, there are }{Chapter~\ref{compliance-understanding-whos-enforcing}

\section{GPLv2~\S5: Acceptance, Copyright Style}

\label{GPLv2s5}

\chapter{GPL Version 3}

\label{GPLv3}

includes text that was adapted (with permission) from text that FSF

originally published as part of the so-called ``rationale documents'' for the

various discussion drafts of GPLv3.

complexity of the license.  The FSF stated at the start of the GPLv3 process

that they would have liked to oblige those who have asked for a simpler and

shorter GPL\@.  Ultimately, the FSF gave priority to making GPLv3 a better

The FSF had many different, important goals in seeking to upgrade to GPLv3.

However, one important goal that is often lost in the discussion of policy

set forth in GPLv3~\S5, as described later in this tutorial in its

\S~\ref{GPLv3s5}).  Here in GPLv3~\S0, ``modify'' refers to basic copyright

rights, and then this definition of ``modify'' is used to define ``modified

\subsection{The Covered Work}

However, in isolation, (a) would be too permissive, as it would sometimes

allowing distributors to evade important GPL requirements.  Part (b) reigns

system library may provide and still qualify for the exception.  The goal is

to ensure system libraries are truly adjunct to a major essential operating

system component, compiler, or interpreter.  The more low-level the

to run is confined to the \textit{unmodified} Program.  This confinement is

unfortunately necessary since Programs that do not qualify as a User Product

in GPLv3~\S6 (see \S~\ref{user-product} in this tutorial) might have certain

  \S~\ref{freedom-to-run} of this tutorial for the details on ``the freedom to

  run''.}

to an upstream distributor's server and arrange with the operator of that

server to keep the source code available for copying for as long as the

downstream distributor enables access to the object code.  This codifies

% FIXME-LATER: perhaps in enforcement section, but maybe here, note about

% ``slow down'' on source downloads being a compliance problem. 

\subsection{User Products, Installation Information and Device Lock-Down}

technical measures such as signature checks in hardware to prevent

modification of GPL'd software on a device.

With these principles in the background, GPLv3~\S7  answers the following

questions: 

\begin{enumerate}

affect users' rights?

\item When and how may a licensee add terms to code being

claims that would be infringed only as a consequence of further

modification of the work.''  The set of essential patent

claims licensed  is fixed by the

cannot expand as a work is further modified downstream.  (If it could,

then any software patent claim would be included, since any software

patent claim can be infringed by some further modification of the

\section{GPLv3~\S12: Familiar as GPLv2~\S7}

GPLv2~\S7.  This is an important provision that ensures a catch-all to ensure

that nothing ``surprising'' interferes with the continued conveyance safely

under copyleft.

license, but one compatible with GPLv3. 

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

does not automatically apply to all GPLv3'd works.

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

and dependable, and the users be allowed to have unfettered access to

it. Free Software, and GPL'd software in particular (because IBM can

be assured that proprietary versions of the same software will not

For example, charging a ``convenience fee'' for Free Software,

when set at a reasonable price (around \$60 or so), can produce some

complying with the GPL from a users' perspective gives substantially fewer

headaches than proprietary license compliance.

versions of GPL'd software, the burden is a bit higher, but not by

much. The glib answer is that by releasing the whole product as Free

Software, it is always easy to comply with the GPL. However,