\begin{itemize}

  \item How to build a plan for proper and successful compliance with the GPL

  \item How existing GPL'd software can be used in existing enterprises

  \item How best to understand the complexities regarding derivative

        works of software

it was created to embody and defend a set of principles that were set

forth at the founding of the GNU project and the Free Software Foundation

(FSF)---the organization that upholds, defends and promotes the philosophy

terms and conditions is a basic understanding of the principles behind it.

designed to defend and uphold these principles.

\section{The Free Software Definition}

software, governs copying, modifying, and redistributing that

software.\footnote{Copyright law in general also governs ``public

  performance'' of copyrighted works. There is no generally agreed

the author) of the work controls how others may copy, modify and/or

distribute the work. For proprietary software, these controls are used to

prohibit these activities. In addition, proprietary software distributors

\section{Complexities of Two Simultaneously Popular Copylefts}

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

\label{run-and-verbatim}

This chapter begins the deep discussion of the details of the terms of

0--2. These are the straightforward sections of the GPL that define the

simplest rights that the user receives.

\label{GPLs0}

copyright law. It specifically points out that it is the ``copyright

holder'' who decides if a work is licensed under its terms and explains

how the copyright holder might indicate this fact.

covered by this License; they are outside its scope.

\end{quote}

In essence, the license governs \emph{only} those activities, and all other

(which they cannot; see Sections~\ref{GPLs6} and~\ref{GPLs7}). This is

very important, because the Free Software community heavily supports

users' rights to ``fair use'' and ``unregulated use'' of copyrighted

to fair and unregulated uses.

Fair use of copyrighted material is an established legal doctrine that

\medskip

to run specifically by stating the following:

\begin{quote}

''The act of running the Program is not restricted.''

even the GNU GPL --- can be blamed for this. Legislators and court

opinions must give us guidance to decide the border cases.

\label{GPLs1}

exactly as it was received. This section is quite straightforward.

However, there are a few details worth noting here.

We digress for this chapter from our discussion of GPL's exact text to

consider the matter of derivative works --- a concept that we must

Software licensing in general, relies critically on the concept of

``derivative work'' since software that is ``independent,'' (i.e., not

``derivative'') of Free Software need not abide by the terms of the

In this chapter, we discuss the two core sections that define the rights

and obligations for those who modify, improve, and/or redistribute GPL'd

software. These sections, \S\S 2--3, define the central core rights and

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

freedom along the distribution chain. \S 2 is the only place in the GPL

source code. \S 3 addresses the matter of creation and distribution of

binary versions.

terms of \S\S 1--2, so all the material previously discussed applies

here. However, \S 3 must go a bit further. Access to the software's

source code is an incontestable prerequisite for the exercise of the

complete source, it would not be possible to make changes that were

actually directly derived from the version received.

seen in FSF's GPL enforcement. Under GPL, if you pay a high price for

a copy of GPL'd binaries (which comes with corresponding source, of

course), you have the freedom to redistribute that work at any fee you

GPL --- including the freedom to modify, rebuild, and redistribute the

source code.

would unfairly favor large companies. \S 3(b) allows the

separation of the binary software from the key tool that people can use

to exercise their freedom. The GPL permits this separation because it is

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

source code provision would be unfairly shifted to the companies'

customers. A customer, who had received binaries with a \S 3(b)-compliant

merely to give a copy of the software to a friend who needed it. \S 3(c)

reshifts this burden to entity who benefits from \S 3(b).

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

\chapter{The Implied Patent Grant in GPL}

to consider the interaction between the terms of GPL and patent law. The

licensees more rights to a licensor's patents than those licenses that

purport to address the issue. This is the case because patent law, under

the doctrine of implied license, gives to each distributee of a patented

to prevent the application of the implied license doctrine to Free

Software, because software licensed under the GPL grants the licensee the

right to make, use, and sell the software, each of which are exclusive

grant the licensee the right to do those things under any patents the

licensor may have that cover the software or its reasonably contemplated

software is what would be considered ``uses of the [software] to which

the parties might reasonably contemplate the product will be put.'' A

larger in scope than the express license in other Free Software

licenses with express patent grants, in that, the patent license

clause of many of those licenses are specifically limited to the

patent claims covered by the code as licensed by the patentee.

under the doctrine of implied patent license, is free to practice any

patent claims held by the licensor that cover ``reasonably contemplated

uses'' of the GPL'd code, which may very well include creation and

This theory comports well with the idea of Free Software, whereby software

is distributed amongst many entities within the community for the purpose

of constant evolution and improvement. In this way, the law of implied

benefits from the licensing of patents to any single community member.

worthless. To the contrary, the patents are still valid and enforceable

against either:

 \renewcommand{\theenumi}{\alph{enumi}}

 \renewcommand{\labelenumi}{\textup{(\theenumi)}}

  holder, and

with respect to the licensed software.

\end{enumerate}

\newcommand{\compA}{$\mathcal{A}$}

For example, if Company \compA{} has a patent on advanced Web browsing, but

cannot assert the patent against any party that takes a license to its

infringement of the patent, because the implied patent license only

Company \compB{} distributes a competitive advanced Web browsing program,

Company \compA{} is free to assert its patent against any user or

distributor of that product. It is irrelevant whether Company \compB's

implied licenses to Company \compA's patent.

This result also reassures companies that they need not fear losing their

terms can benefit from the implied patent license. To continue the

example above, Company \compB{} does not receive a free ride on Company

\compA's patent, as Company \compB{} has not licensed-in and then

\compB{} does do that, however, Company \compA{} still has not lost

competitive advantage against Company \compB{}, as Company \compB{} must then,

when it re-distributes Company \compA's program, grant an implied license

to any of its patents that cover the program. Further, if Company \compB{}

relicenses an improved version of Company A's program, it must do so under

are impliedly licensed to any licensee. As such, the only way Company

\compB{} can benefit from Company \compA's implied patent license, is if it,

itself, distributes Company \compA's software program and grants an

\chapter{Defending Freedom on Many Fronts}

Chapters~\ref{run-and-verbatim} and ~\ref{source-and-binary} presented the

are enforceable, are kept to the confines of copyright law, and are not

trumped by other copyright agreements or components of other entirely

separate legal systems. In short, while \S\S 0--3 are the parts of the

the parts of the license that keep the playing field clear so that \S\S

0--3 can do their jobs.

\label{GPLs4}

strange that a license with the goal of defending users' and programmers'

freedoms for perpetuity in an irrevocable way would have such a clause.

However, upon further examination, the difference between irrevocability

  nearly perpetual, even though the Constitution forbids perpetual

  copyright.} The copyright holder has the right to relicense the same

work under different licenses (see Section~\ref{Proprietary Relicensing}

already granted.

In fact, when an entity looses their right to copy, modify and distribute

then all rights under the license --- even those otherwise permitted for

those who have not violated --- terminate automatically.

they are stuck. They must completely cease and desist from all

copying, modification and distribution of that GPL'd software.

would ever consider undertaking or even endorsing, it is a legal way for

copyright holders to proceed.

\label{GPLs5}

\S 5 brings us to perhaps the most fundamental misconception and common

most users, programmers, and lawyers alike tend to be more familiar with

EULAs. EULAs are believed by their authors to be contracts, requiring

formal agreement between the licensee and the software distributor to be

other words, the GPL only kicks in when it needs to for the sake of

freedom.

\label{GPLs6}

A point that was glossed over in Section~\ref{GPLs4}'s discussion of \S 4

and it is made so formally by \S 6.

The first sentence in \S 6 ensures that as software propagates down the

new licensee. Under \S 6, the act of distributing automatically grants a

license from the original licensor to the next recipient. This creates a

chain of grants that ensure that everyone in the distribution has rights

making sure that future licensees get no fewer rights than the licensee before.

The second sentence of \S 6 does the opposite; it bounds from the top. It

prohibits any licensor along the distribution chain from placing

additional restrictions on the user. In other words, no additional

The final sentence of \S 6 makes it abundantly clear that no individual

entity in the distribution chain is responsible for the compliance of any

only copyright license allowing you to copy, modify and distribute the

software.

\label{GPLs7}

In essence, \S 7 is a verbosely worded way of saying for non-copyright

Instead, it is inspiring patent holders to share their patents in the same

freedom-defending way that they share their copyrighted works.

\label{GPLs8}

\S 8 is rarely used by copyright holders. Its intention is that if a

particular country, say Unfreedonia, grants particular patents or allows

copyrighted interfaces (no country to our knowledge even permits those

distribution in the countries where such controls do not exist.

It is a partial ``out'' from \S 7. Without \S 8, if a copyright holder

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

\chapter{Odds, Ends, and Absolutely No Warranty}

liability.

\label{GPLs9}

FSF reserves the exclusive right to publish future versions of the GPL\@;

a gigantic community depends on that freedom now. FSF hopes to take all

stakeholders' opinions under advisement.

\label{GPLs10}

\S 10 reminds the licensee of what is already implied by the nature of

program has the prerogative to grant alternative agreements under separate

copyright licenses.

\label{GPLs11}

All warranty disclaimer language tends to be shouted in all capital

Finally, one important point to remember when reading \S 11 is that \S 1

permits the sale of warranty as an additional service, which \S 11 affirms.

\label{GPLs12}

There are many types of warranties, and in some jurisdictions some of them