"Intellectual property, software plagiarism, patents, and copyrights are complicated subjects. This book explains the key elements better than anything else I have seen. I highly recommend it to anyone who develops software or needs to protect proprietary software algorithms, and to all attorneys involved with IP litigation."

-Capers Jones, President, Capers Jones & Associates LLC

"Intellectual property is an engine of growth for our high tech world and a valuable commodity traded in its own right. Bob Zeidman is a leading authority on software intellectual property, and in this book he shares his expertise with us. The book is comprehensive. It contains clear explanations of many difficult subjects. Business people who study it will learn how to protect their IP. Lawyers will use it to understand the specifics of how software embodies IP. Judges will cite it in their decisions on IP litigation."

-Abraham Sofaer, George P. Shultz Senior Fellow in Foreign Policy and National Security Affairs, Hoover Institution, Stanford University

The Definitive Software IP Guide for Developers, Managers, Entrepreneurs, Attorneys, and Consultants

In The Software IP Detective's Handbook, pioneering expert Bob Zeidman-creator of CodeSuite^®, the world's #1 software IP analysis tool-thoroughly covers all technical and legal aspects of IP theft detection. Using his rigorous framework and practical examples, you can accurately determine whether software copying, theft, or infringement has occurred, and fully support your findings in any venue. This book will help you

• Understand the key concepts that underlie software IP analysis
• Compare and correlate source code for signs of theft or infringement
• Uncover signs of copying in object code when source code is inaccessible
• Track malware and third-party code in applications
• Use software clean rooms to avoid IP infringement
• Understand IP issues associated with open source and DMCA

Visit to download a free trial version of CodeSuite^®, the #1 tool for detecting software copying.

Bob Zeidman is president and founder of Zeidman Consulting (), a leading Silicon Valley contract R&D firm specializing in engineering consulting on IP disputes. Since 1983, he has designed chips and boards for RISC-based systems, network equipment, and other complex systems. His clients have included Apple, Cisco, Cadence, Facebook, Symantec, Texas Instruments, and Zynga. Zeidman has worked on and testified in cases involving billions of dollars in disputed IP. He is also president and founder of Software Analysis and Forensic Engineering Corporation (). A prolific writer and instructor, he holds multiple patents, an M.S.E.E. from Stanford, and a B.A. in physics and a B.S. in electrical engineering from Cornell.

Preface xxi

Acknowledgments xxiii

About the Author xxv

Part I: Introduction 1

Objectives 2

Intended Audience 2

Chapter 1: About this Book 5

Part I: Introduction 6

Part II: Software 6

Part III: Intellectual Property 6

Part IV: Source Code Differentiation 9

Part V: Source Code Correlation 9

Part VI: Object and Source/Object Code Correlation 10

Part VII: Source Code Cross-Correlation 10

Part VIII: Detecting Software IP Theft and Infringement 11

Part IX: Miscellaneous Topics 11

Part X: Past, Present, and Future 11

Chapter 2: Intellectual Property Crime 13

2.1 The Extent of IP Theft 14

Part II: Software 21

Objectives 22

Intended Audience 22

Chapter 3: Source Code 23

3.1 Programming Languages 24

3.2 Functions, Methods, Procedures, Routines, and Subroutines 26

3.3 Files 32

3.4 Programs 35

3.5 Executing Source Code 36

Chapter 4: Object Code and Assembly Code 39

4.1 Object Code 39

4.2 Assembly Code 40

4.3 Files 43

4.4 Programs 44

Chapter 5: Scripts, Intermediate Code, Macros, and Synthesis Primitives 45

5.1 Scripts 45

5.2 Intermediate Code 47

5.3 Macros 48

5.4 Synthesis Primitives 49

Part III: Intellectual Property 53

Objectives 55

Intended Audience 55

Chapter 6: Copyrights 57

6.1 The History of Copyrights 57

6.2 Copyright Protections 60

6.3 Software Copyrights 63

6.4 Allowable and Nonallowable Uses of Copyrighted Code 72

Chapter 7: Patents 79

7.1 The History of Patents 80

7.2 Types of Patents 81

7.3 Parts of a Patent 82

7.4 Patenting an Invention 85

7.5 Special Types of Patent Applications 86

7.6 Software Patents 90

7.7 Software Patent Controversy 91

7.8 Patent Infringement 95

7.9 NPEs and Trolls 99

Chapter 8: Trade Secrets 103

8.1 The History of Trade Secrets 103

8.2 Uniform Trade Secrets Act (UTSA) 104

8.3 Economic Espionage Act 105

8.4 Aspects of a Trade Secret 106

8.5 Trade Secret Theft 111

8.6 Patent or Trade Secret? 112

Chapter 9: Software Forensics 113

9.1 Forensic Science 115

9.2 Forensic Engineering 116

9.3 Digital Forensics 119

9.4 Software Forensics 120

9.5 Thoughts on Requirements for Testifying 121

Part IV: Source Code Differentiation 125

Objectives 126

Intended Audience 126

Chapter 10: Theory 127

10.1 Diff 128

10.2 Differentiation 133

10.3 Types of Similarity 135

10.4 Measuring Similar Lines 136

10.5 Measuring File Similarity 140

10.6 Measuring Similar Programs 142

Chapter 11: Implementation 147

11.1 Creating and Comparing Arrays 147

11.2 Number of Optimal Match Score Combinations 151

11.3 Choosing Optimal Match Scores for Calculating File Similarity 153

11.4 Choosing File Similarity Scores for Reporting Program Similarity 161

Chapter 12: Applications 165

12.1 Finding Similar Code 165

12.2 Measuring Source Code Evolution 168

Part V: Source Code Correlation 183

Objectives 185

Intended Audience 185

Chapter 13: Software Plagiarism Detection 187

13.1 The History of Plagiarism Detection 187

13.2 Problems with Previous Algorithms 189

13.3 Requirements for Good Algorithms 192

Chapter 14: Source Code Characterization 197

14.1 Statements 199

14.2 Comments 206

14.3 Strings 207

Chapter 15: Theory 209

15.1 Practical Definition 210

15.2 Comparing Different Programming Languages 213

15.3 Mathematical Definitions 214

15.4 Source Code Correlation Mathematics 215

15.5 Source Code Examples 216

15.6 Unique Elements 218

15.7 Statement Correlation 219

15.8 Comment/String Correlation 223

15.9 Identifier Correlation 225

15.10 Instruction Sequence Correlation 227

15.11 Overall Correlation 228

Chapter 16: Implementation 233

16.1 Creating Arrays from Source Code 234

16.2 Statement Correlation 239

16.3 Comment/String Correlation 240

16.4 Identifier Correla…