Judgement Briefs

Intellectual Property Rights

Computer Associates International, Inc. v. Altai, Inc.

982 F.2d 693 (2d Cir. 1992)

Citation
982 F.2d 693 (2d Cir. 1992)
Court
U.S. Court of Appeals for the Second Circuit
Date
22 June 1992
Bench
Altimari, Mahoney and Walker, Circuit Judges

Facts

  • Computer Associates developed a program called CA-SCHEDULER.
  • One component, ADAPTER, enabled the program to operate on different computer systems.
  • Altai employed a former Computer Associates programmer who copied parts of ADAPTER while creating Altai’s OSCAR 3.4 program.
  • After learning of the copying, Altai removed the copied version and created OSCAR 3.5 through a “clean-room” process involving programmers who had not seen ADAPTER’s code.
  • Computer Associates alleged that both versions infringed not only its literal code but also the non-literal structure, sequence and organisation of its program.
  • The District Court found OSCAR 3.4 infringing but held that OSCAR 3.5 did not copy protectable expression.
  • Computer Associates appealed.

Issue

  • How copyright infringement should be assessed for non-literal elements of computer programs.
  • Which aspects of program structure are ideas, functional necessities or otherwise unprotected.
  • Whether OSCAR 3.5 remained substantially similar after excluding unprotectable material.

Rule

  • Copyright protects computer-program expression but not:
  • ideas;
  • algorithms and methods;
  • elements dictated by efficiency;
  • external compatibility requirements;
  • public-domain material.
  • The “abstraction–filtration–comparison” test applies:
  • Abstraction: break the program into levels, from specific code to general purpose.
  • Filtration: remove ideas and elements dictated by efficiency, external factors or public domain.
  • Comparison: compare the remaining protectable expression with the accused program.
  • Substantial similarity must concern protected expression rather than functional resemblance.

Application

  • At the lowest level, exact source or object code may receive copyright protection.
  • At higher levels, program modules and architecture increasingly reflect functional concepts.
  • The Court refused to treat the entire structure of ADAPTER as protected merely because Computer Associates had designed it.
  • Some organisational choices followed naturally from:
  • the program’s required functions;
  • compatibility with operating systems;
  • standard programming practices;
  • efficiency concerns.
  • Those elements had to be filtered out.
  • Otherwise, copyright would grant control over methods of operation and software functionality.
  • OSCAR 3.4 contained copied code and was therefore infringing.
  • OSCAR 3.5, however, was independently rewritten.
  • After filtering out unprotectable similarities, the remaining overlap was insufficient to show appropriation of Computer Associates’ expression.
  • Functional equivalence was not enough.
  • Two programs may perform the same task and use similar general architecture without infringing if those similarities arise from the problem being solved.
  • The test protected genuine creative programming choices while preserving room for compatible and competing software.
  • It also required courts to conduct a disciplined technical analysis instead of relying upon an impression that two programs “look” structurally similar.

Conclusion

  • The Second Circuit approved the abstraction–filtration–comparison test.
  • OSCAR 3.4 infringed because it contained copied code.
  • OSCAR 3.5 did not infringe because, after filtering out ideas and functional constraints, no substantial protected similarity remained.
  • Use this case for: non-literal software infringement is tested by abstracting the program, filtering unprotectable functional elements and comparing only the remaining expression.