By the first year of this century, approximately 17,000 open source projects were active on the SourceForge servers (www.sourceforge.net). Four years later there are over 74,000 such projects and more than 775,000 registered SourceForge users. The majority of that open source software is currently licensed under the GPL or BSD licenses; the rest use one of about fifty other licenses based on the same open source principles.

Open source is now dominating many of the market conversations in the software industry. While software companies continue to release valuable and high-quality products under proprietary licenses, most are also embracing open source product development and distribution models as well as the software licenses that make those models possible.

This book is about the law but it is not written for lawyers. You will not find citations to case law or rigorous academic analyses suitable for publication in a law journal. This book is written for my friends in the open source community who write and distribute software and who are confused about which licenses to use. It is also written for our customers who are concerned about how software licenses may affect them and their businesses. It seeks to dispel myths and fears about open source software licensing and to explain the legal context in which open source software exists.

Open source is built upon a foundation of intellectual property law, particularly copyright law. Open source software is owned by its authors, who license it to the public under generous terms. Open source licenses do not seek to destroy or steal intellectual property. The first chapters of this book explain the intellectual property laws that make open source licensing possible.

The following chapters describe the first broad category of open source licenses, what I call academic licenses to acknowledge their heritage in universities. These academic licenses allow software to be used, copied, modified, and distributed, even with proprietary software?and their source code is included. These licensors generously donate their software to the public for use by anyone.

The GPL, and the MPL, CPL, and OSL licenses that followed it, strike what I call a reciprocal bargain. Licensor and licensees share a public commons of open source software, but any modifications to that software must be distributed under the same license. These four licenses are much more complex than the academic licenses and so I devote a chapter to each of them.

Choosing a license to apply to your open source software is not an easy decision and so I devote an entire chapter to it. The answer depends intricately upon your business model, on your software and product architecture, and on understanding who owns the intellectual property in your products. If you expect a checklist method to select a license, don?t bother reading this chapter; it cannot be so easy.

Eventually, a licensor or licensee may need to enforce the terms and conditions of an open source license. I devote an entire chapter to satisfying the curiosity of those who may want to sue?or who are afraid of being sued?under an open source license.

Finally, I begin to address a potentially bigger issue than open source. Open standards are really the battlefield on which we will determine whether software can truly be free and open. That topic deserves a book of its own someday; this isn?t it, but I?m making a start.

Turning a software license into interesting reading is probably an insurmountable challenge. There is no other way than reading the words of a license to understand what it means. And so, for those of you who won?t actually plod your way through the detailed explanations of licenses herein, I want to give you the conclusion.

As a user of open source software you may go forth and live free. None of the licenses in this book restrict in any way your use of open source software. But if you are more directly involved in the creation, modification, or distribution of software, or if you manage or advise the in-licensing of software into your company, you should at the very least consult your attorney to make sure you don?t commit to more than you?re willing to deliver. This book may help you ask your attorney the right questions.

“I have studied Rosens book in detail and am impressed with its scope and content. I strongly recommend it to anybody interested in the current controversies surrounding open source licensing.”

John Terpstra, Samba.org; cofounder, Samba-Team

“Linux and open source software have forever altered the computing landscape. The important conversations no longer revolve around the technology but rather the business and legal issues. Rosens book is must reading for anyone using or providing open source solutions.”

Stuart Open Source Development Labs

A Complete Guide to the Law of Open Source for Developers, Managers, and Lawyers

Now that open source software is blossoming around the world, it is crucial to understand how open source licenses workand their solid legal foundations. Open Source Initiative general counsel Lawrence Rosen presents a plain-English guide to open source law for developers, managers, users, and lawyers. Rosen clearly explains the intellectual property laws that support open source licensing, carefully reviews todays leading licenses, and helps you make the best choices for your project or organization. Coverage includes:

• Explanation of why the SCO litigation and other attacks wont derail open source
• Dispelling the myths of open source licensing
• Intellectual property law for nonlawyers: ownership and licensing of copyrights, patents, and trademarks
• “Academic licenses”: BSD, MIT, Apache, and beyond
• The “reciprocal bargain” at the heart of the GPL
• Alternative licenses: Mozilla, CPL, OSL and AFL
• Benefits of open source, and the obligations and risks facing businesses that deploy open source software
• Choosing the right license: considering business models, product architecture, IP ownership,
license compatibility issues, relicensing, and more
• Enforcing the terms and conditions of open source licenses
• Shared source, eventual source, and other alternative models to open source
• Protecting yourself against lawsuits

Preamble xix

Chapter 1: Freedom and Open Source 1

The Language of Freedom 1

Defining Open Source 2

Open Source Principles 8

Chapter 2: Intellectual Property 13

Dominion Over Property 13

Right Brain and Left Brain 15

Acquiring Copyrights and Patents 17

Original Works of Authorship 19

Works Made for Hire 20

Exclusive Rights of Copyright and Patent Owners 22

Copies 24

Exceptions to the Exclusive Right to Make Copies 25

Collective and Derivative Works 26

The Chain of Title for Copyright 28

The Chain of Title for Patents 30

Joint Works 32

Assigning Ownership 33

Duration of Copyright and Patent 36

Trademarks 37

Exceptions to Intellectual Property Protection 39

Chapter 3: Distribution of Software 41

Contributors and Distributors 41

Distribution 42

Open Source Collaboration 43

Contributor Agreements 45

What About Users? 49

Chapter 4: Taxonomy of Licenses 51

What Is a License? 51

Bare Licenses 53

Licenses as Contracts 57

Patent Licenses 66

Template Licenses 68

Types of Open Source Licenses 69

Chapter 5: Academic Licenses 73

The BSD Gift of Freedom 73

BSD License as Template 77

The BSD License Grant 77

Source and Binary Forms of Code 79

Conditions under the BSD 80

Warranty and Liability Disclaimer 83

The MIT License 85

The Right to Sublicense 87

The Warranty of Noninfringement 89

The Apache License 91

Protecting Trademarks 92

The Apache Contributor License Agreement 93

The Artistic License 95

License Preambles 96

When Amateurs Write Licenses 97

Big Picture of Academic Licenses 101

Apache License Version 2.0 102

Chapter 6: Reciprocity and the GPL 103

The GPL Bargain 103

Copyleft and Reciprocity 105

Policy Objectives 107

The Preamble to the GPL 109

GPL as Template 112

The GPL Applies to Programs 113

Linking to GPL Software 115

Copyright Law and Linking 119

The LGPL Alternative 121

GPL Grant of License 125

Access to Source Code 128

“At No Charge” 131

Other Obligations in the GPL 133

The GPL and Patents 134

Accepting the GPL 136

Chapter 7: The Mozilla Public License (MPL) 141

The Mozilla Story 141

The MPL Reciprocity Bargain 143

Contributors and Modifications 145

The MPL and Patents 147

Defending Against Patents 154

Other Important MPL License Provisions 156

Other Corporate Licenses 159

Chapter 8: The Common Public License (CPL) 161

CPL as a Template 161

A Digression about Well-Written Licenses 162

Grant of Copyright and Patent Licenses 163

Reciprocity under the CPL 167

Exception to Reciprocity 168

Patent Defense 170

Defend and Indemnify 173

Ownership of the CPL License 176

Chapter 9: The OSL and the AFL 179

Academic or Reciprocal? 179

Initial Paragraph of OSL/AFL 182

Copyright and Licensing Notice 225

Chapter 10: Choosing an Open Source License 229

How Licenses Are Chosen 229

The Free-Rider Problem 230

Making Money from Open Source 231

In-Licensing 232

Out-Licensing 235

Contributions to Projects 238

License Compatibility for Collective Works 241

License Compatibility for Derivative Works 243

Relicensing 252

Chapter 11: Shared Source, Eventual Source, and Other Licensing Models 255

Alternatives to Open Source 255

Shared Source 256

Public Source 259

Dual and Multiple Licensing 262

Eventual Source and Scheduled Licensing 264

Combining Licensing Models 267

Chapter 12: Open Source Litigation 269

Owning a Cause of Action 269

Damages 271

Injunctions 274

Standing to Sue 276

Burden of Proof 277

Enforcing the Terms of a Contract 280

Disputes over Ownership of Intellectual Property 283

Disputes over Derivative Works 284

Patent Infringement Litigation 289

SCO vs. Open Source 290

Chapter 13: Open Standards 295

Defining Open Standards 295

Open Specifications 296

Enforcing the Standard by Copyright Restrictions 298

Licensing the Test Suite: The Open Group License 299

Discouraging Forks: Suns SISSL 301

Patents on Open Standards 303

Reasonable and Nondiscriminatory 304

Royalty Free 306

The W3C Patent License 307

Justifying Open Standards and Open Source 310

The Open Source Paradigm 313

Appendices 315

Index 385

About the Author 397