Editing Rational Software (section)

{{Short description|Defunct software company}}
{{More citations needed|date=October 2020}}
{{Update|part=article|date=July 2023}}{{Infobox company
| name             = Rational Software
| logo             = [[File:RationalSoftware.png|180px|Rational Software]]
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| fate             = Acquired by [[IBM]]
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| foundation       = {{Start date|1981}}
| founder          = Paul Levy and [[Mike Devlin (entrepreneur)|Mike Devlin]]
| defunct          = {{End date|2003|02|20}}
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| key_people       = [[Mike Devlin (entrepreneur)|Mike Devlin]] (previous CEO)
| industry         = Application development tools
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| homepage         = {{URL|https://www.ibm.com/software/uk/rational/}}
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}}{{About-distinguish|the software company that specializes in software architecture solutions|Rational Systems}}
'''Rational Machines''' is an enterprise founded by Paul Levy and [[Mike Devlin (entrepreneur)|Mike Devlin]] in 1981 to provide tools to expand the use of modern software engineering practices, particularly [[Modular programming|explicit modular architecture]] and [[Iterative and incremental development|iterative development]]. It changed its name in 1994 to '''Rational Software''', and was sold for US$2.1 billion (equivalent to current US${{Format price|{{Inflation|US|2100000000|2003}}}}{{Inflation-fn|US}}) to [[IBM]] on February 21,<ref>{{cite web | url=https://www.lexpert.ca/big-deals/ibm-acquires-rational-software/343838 | title=IBM Acquires Rational Software }}</ref> 2003.