Tales from 20 Years of Copyleft Enforcement

Bradley M. Kuhn

Saturday 4 June 2016

The Guiding Moral Theory

Fighting for software freedom means trying to build a world where every user has the unencumbered, inalienable right to copy, share, modify, redistribute, upgrade and improve all the software on which they rely.

The Final Goal

IMO, the final goal of the software freedom movement is to change the world so that all software available is Free Software, giving every users those key inalienable rights.

What is Copyleft?

Formal Definition of Copyleft

Copyleft is a strategy of utilizing copyright law to pursue the policy goal of fostering & encouraging the equal & inalienable right to copy, share, modify & improve creative works of authorship. Copyleft … describes any method that utilizes the copyright system to achieve the aforementioned goal. Copyleft as a concept is usually implemented in the details of a specific copyright license … Copyright holders of creative work can unilaterally implement these licenses for their own works to build communities that collaboratively share & improve those copylefted creative works.

— Definition of copyleft from copyleft.org

It’s Not Magic

Copyleft is not magic pixie dust.

What is GPL Enforcement?

But It’s Not Really About Upstream.

What’s a GPL Violation?

Earliest Copyleft Programs

Second Copyleft Program

The NeXT Shall be First

Earliest Post I Could Find

Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!cs.utexas.edu!usc!apple!bbn!bbn.com!bpalmer
From: bpal…@bbn.com (Brian Palmer)
Newsgroups: gnu.misc.discuss
Subject: Objective Gnu?
Message-ID: <5768@bbn.COM>
Date: 19 Sep 89 15:36:16 GMT

In “The NeXT Book” by Bruce Webster, he says: (page 134):

Objective C is based on the Gnu C compiler developed by Richard Stallman. Release 0.9 has merged the Objective C syntax with the the Gnu C compiler to speed up compilation and to produce faster, more efficient code.

Are they using FSF software in their product? Or is Webster just badly explaining the situation … and Objective C is just preprocessing and passing C to gcc.

Otherwise Gang, I see a Copyleft violation right?


NeXT Answers

Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!apple!gem.mps.ohio-state.edu!tut.cis.ohio-state.edu!NEXT.COM!Matthew_Self
From: Matthew_S…@NEXT.COM<br/> Newsgroups: gnu.gcc
Subject: Objective-C front end for GCC from NeXT
Message-ID: <8909210104.AA14825@batcomputer.NeXT.COM>
Date: 21 Sep 89 01:01:50 GMT
Sender: dae…@tut.cis.ohio-state.edu<br/>

In response to Steve Simmons’ inquiry about an Objective-C front-end for GCC, NeXT will be making our modifications to GCC for Objective-C available very soon.

Once GCC-1.36 is released (any day now), I will create a patch kit which will be announced on this mailing list. (The modifications are very small.)

Matthew Self

Tar Wars

A long time ago, in a city far far away, the Empires had taken GNU tar and placed it into proprietary backup solutions. A small band of freedom fighters enforced the GPL to liberate users who were oppressed by the proprietary nature of GPL violators.

Tar Wars

My First CCS Check

Enforcement is Technical

How GPLv3 says CCS.

The “Corresponding Source” for a work in object code form means all the source code needed to generate, install, and (for an executable work) run the object code and to modify the work, including scripts to control those activities.

— GPLv3§1

How GPLv2 says CCS.

You may copy and distribute the Program (or a work based on it, under § 2) in object code or executable form under the terms of § 1 & 2 above provided that you … [a]ccompany it with the complete corresponding machine-readable source code … The source code for a work means the preferred form of the work for making modifications to it. For an executable work, complete source code means all the source code for all modules it contains, plus any associated interface definition files, plus the scripts used to control compilation and installation of the executable.

— GPLv2§3

The 11 Words That Consumed My Life

the scripts used to control compilation and installation of the executable.

— GPLv2§3

The 11 Words That Consumed My Life

the scripts used to control compilation and installation of the executable.

— GPLv2§3

Tar Wars Continue

Court May Not Mandate Source Release

Coalition of the Willing

Compliance Takes Soooo Long


GCC Redux, 2003-2005

Enforcement Corruption: MySQL

Embedded Violations Prevalent

The First Era of GPL Litigation

Success in Court

The Default Judgment


The Default Judgment

Violators Are Often Corrupt

Age of the Savvy Violator

The Tempest in the Toybox

Anti-enforcement industry consortia

A New Coalition

Why Linux?

Linux’s GPL Elephant

Zero-Sum Game

Linux’s Combined Work Test Case

VMware’s Incorporation of Linux

Status of VMware Suit

Funding Enforcement

Funding Enforcement

More Info / Talk License

Presentation and slides are: Copyright © 2012, 2014, 2015, 2016 Bradley M. Kuhn, and are licensed under the Creative Commons Attribution-Share Alike 4.0 International License.

Some images included herein are ©’ed by others. I believe my use of those images is fair use under USA © law. However, I suggest you remove such images if you redistribute these slides under CC-By-SA 4.0.

ZFS (Since You Asked)

ZFS (Since You Asked)