Table of Contents:

Introduction to the online version


Preface to the printed version

Copyright Overview

Software Copyright

- History

- Copyrights or Patents?

- Object Code

- RAM Copies

- Beyond Mere Copying

   - Abstraction, Filtration, Comparison

   - Methods of Operation

   - Applying The AFC Test

- Reverse Engineering

- Other Issues

   - New Software from Old

- Summary

Digital Copyright

Patent Overview

Software Patents

Full treatise table of contents

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Chapter 2: Copyright of Computer Programs

VI. Other Software Copyright Issues

There are a number of aspects of software copyright that have not been considered by the courts but may play a role in future litigation.

VI.A. Source Code and Derivative Works

Copyright for a computer program, under the Copyright Act of 1976, comes into being as the source code for the computer program is being written by the programmer. As Section 102(a) states, “Copyright protection subsists . . . in original works of authorship fixed in any tangible medium of expression,” {FN100: 17 U.S.C. §102(a)} such as keypunch cards, magnetic tape, hard or floppy disks, or even the RAM of the computer. The program does not need to be complete or even functional for copyright protection to come into being.

When additional source statements are added to the computer program, or corrections are made to the computer program, those additions or corrections are a “derivative work” based on the original computer program. Section 101 {FN101: 17 U.S.C. §101} defines a derivative work as “a work based upon one or more preexisting works” and states that “editorial revisions, annotations, elaborations, or other modifications which, as a whole, represent an original work of authorship” are derivative works.

Just as a copyright came into being when the original lines of source code were written by the programmer, so another copyright comes into being for each addition or modification to the source code that shows sufficient originality. Because of this, a computer program generally is protected not by a single copyright but by a series of copyrights starting when it is first written and continuing through the last modification.

However, there is little practical significance in viewing the source code copyrights as a series of separate copyrights rather than a single copyright. If the computer program is not a work made for hire, then all the copyrights will expire at the same time – 70 years after the death of the last surviving author. For works made for hire, the copyrights will expire in the order in which they came into being. The copyright on the original program will expire first, allowing it (but not its later modifications) to enter the public domain, where it can be copied freely. The copyright on each modification will expire at some later time, until all the copyrights have expired and the complete computer program enters the public domain. However, because the copyright for the original source code will not expire for 95 years after it is first published (and 120 years after it is first written, if it remains unpublished), it is unlikely that the fact that part of an outdated, 95-year-old computer program has entered the public domain while a part remains copyrighted will be of any significance.

One situation in which this series of copyrights may be significant when the copyright in the computer program is registered. It is common to register the copyright whenever a major release of the computer program occurs, but not when there has been only a minor change. While the copyright owner can sue for infringement of the copyright only on the material that has been registered, if there have been only minor changes since registration, the copied version will be substantially similar to the registered one – sufficient for a finding of copyright infringement.

It may also be important to look at a computer program as a series of derivative works is when the original author has not written the modifications. For a program written by company employees, it makes no difference because the author under the law for such a work made for hire is the employer. But if there are different authors, then the copyright owner in any work has to authorize the making of any further derivative works and must approve of any distribution of the work that contains his material. Unless ownership and distribution rules are resolved at the time the work is being developed, there could be problems at a later time.

VI.B. Source Code and Object Code

Although copyright comes into being with the writing of the source code, it is the object code – the actual instructions that control the computer when the program is being executed – that copyright generally protects. In most instances, the source code is never revealed to the public, and thus remains protected as a trade secret even though millions and millions of copies of the program are distributed as object code.

Every computer program copyright case treats the copyright in the source code and the object code as equivalent. That is likely because they were decided at a time when there was essentially a one-to-one correspondence between the source code and the object code. The source code was written in assembly language, with each line of the source code corresponding to a single machine instruction (or, if a macro facility existed as part of the assembler, a small predefined series of machine instructions). The source code contained information that made it easier for a programmer to write or understand the program – mnemonics like “ADD” instead of a bit pattern of “01000011” for the addition instruction, the use of symbolic labels for storage or program locations, and the inclusion of comments to annotate the program – which the assembly process removed or replaced as it produced the object code.

With the advent of higher-level programming languages, that is less the case. The compiler for the higher-level language performs a much more complicated translation than was the case for an assembler. It not only produces complex series of object code instructions for each source line but may actually rearrange the statements of the program to produce a more efficient program. There is no longer the one-to-one correspondence between the source code and the object code. This, along with their size, makes it more difficult to reverse engineer (for example, to learn how the program works either by testing or by trying to convert the object code back to source code) a modern computer program, which in turn makes it more likely that any copying will be a literal copying of the entire program.

Even though source code and object code are distinct, it is still useful to maintain the concept that the source code and the object code are just different forms of the same copyrighted work. The Copyright Office regards the source code and object code as equivalent for purposes of registration. In fact, it generally requires a deposit of at least a portion of the source code (generally the first and last 25 pages – see their Circular 61) and questionsany registration that includes only object code.

Where an applicant is unable or unwilling to deposit source code, he/she must state in writing that the work as deposited in object code contains copyrightable authorship. The Office will send a letter stating that registration has been made under its rule of doubt and warning that it has not determined the existence of copyrightable authorship. {FN102: Copyright Office Circular 61: “Copyright Registration for Computer Programs,” at 2}

VI.C. Source Code and Displays

The source code copyright that protects the object code may also cover any screen displays produced by the computer program. These would be considered “audiovisual works” under the Copyright Act, defined in Section 101 as

works that consist of a series of related images which are intrinsically intended to be shown by the use of machines or devices such as projectors, viewers, or electronic equipment, together with accompanying sounds, if any, regardless of the nature of the material objects, such as films or tapes, in which the works are embodied. {FN103: 17 U.S.C. §101}

Video games, consisting of a series of displays controlled by the computer program, are particularly suitable to regard as audiovisual works. But because Section 106 grants no exclusive right to copyright owners of audiovisual works that it does not also grant to copyright owners of literary works like computer programs and audiovisual works, there is little reason to treat the two aspects of some programs separately. The Copyright Office has recognized that computer programs may be both literary works and audiovisual works, and it requires only a single registration for both aspects.

   Copyright protection for computer screen displays, including videogames, has been an issue in the courts for some time. Courts have differed in their opinions regarding whether screen displays may be registered separately.

   The Copyright Office has consistently believed that a single registration is sufficient to protect the copyright in a computer program and related screen displays, including videogames, without a separate registration for the screen displays or a specific reference to them on the application for the computer program. An application may give a general description in the “nature of authorship” space, such as “entire work” or “computer program.” This description will cover any copyrightable authorship contained in the computer program and screen displays, regardless of whether identifying material for the screen is deposited. {FN104: Copyright Office Circular 61 at 3}

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Copyright © 2002, Lee A. Hollaar. See information regarding permitted usage.