Private company

Rational Software

Rational Machines was an enterprise founded by Paul Levy and Mike Devlin in 1981 to provide tools to expand the use of modern software engineering practices, particularly explicit modular.1

Last updated Oct 18, 2026.

Overview

1991Founded1

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Rational Machines was an enterprise founded by Paul Levy and Mike Devlin in 1981 to provide tools to expand the use of modern software engineering practices, particularly explicit modular architecture and iterative development. It changed its name in 1994 to Rational Software, and was sold for US$2.1 billion (equivalent to current US$3.68 billion) to IBM on February 21, 2003.2

Leadership

Who has led Rational Software, and when. Pick a name to see everywhere that person has worked.

Timeline

  1. 2003Dissolved Dissolved1
  2. 1991Founded Founded1

Sources

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