This one-day course presents the details of five different GPL

compliance cases handled by FSF's GPL Compliance Laboratory. Each case

offers unique insights into problems that can arise when the terms of

the GPL are not properly followed, and how diplomatic negotiation between

the violator and the copyright holder can yield positive results for

both parties.

Attendees should have successfully completely the course, a ``Detailed

Study and Analysis of the GPL and LGPL,'' as the material from that

course forms the building blocks for this material.

This course is of most interest to lawyers who have clients or

employers that deal with Free Software on a regular basis. However,

technical managers and executives whose businesses use or distribute

Free Software will also find the course very helpful.

\bigskip

These course materials are merely a summary of the highlights of the

course presented. Please be aware that during the actual GPL course, class

discussion supplements this printed curriculum. Simply reading it is

not equivalent to attending the course.

\chapter{Overview of Community Enforcement}

The GPL is a Free Software license with legal teeth. Unlike licenses like

the X11-style or various BSD licenses, the GPL (and by extension, the LGPL) is

designed to defend as well as grant freedom. We saw in the last course

that the GPL uses copyright law as a mechanism to grant all the key freedoms

essential in Free Software, but also to ensure that those freedoms

propagate throughout the distribution chain of the software.

\section{Termination Begins Enforcement}

As we have learned, the assurance that Free Software under the GPL remains

Free Software is accomplished through various terms of the GPL: \S 3 ensures

that binaries are always accompanied with source; \S 2 ensures that the

sources are adequate, complete and usable; \S 6 and \S 7 ensure that the

license of the software is always the GPL for everyone, and that no other

legal agreements or licenses trump the GPL. It is \S 4, however, that ensures

that the GPL can be enforced.

Thus, \S 4 is where we begin our discussion of GPL enforcement. This

clause is where the legal teeth of the license are rooted. As a copyright

license, the GPL governs only the activities governed by copyright law ---

copying, modifying and redistributing computer software. Unlike most