Editing Unix System Laboratories (section)

{{Use mdy dates|date=May 2018}}
{{Short description|Former software laboratory}}
{{Use American English|date = April 2019}}
{{Infobox company
| name             = UNIX System Laboratories
| logo             = File:Unix System Laboratories logo.svg
| image            = Unix System Laboratories building in Summit.jpg
| image_caption    = USL logo as it appeared atop the headquarters building in Summit, New Jersey
| type             = [[Private company|Private]]
| traded_as        = 
| fate             = Acquired by [[Novell]] {{End date|1993|06}}
| predecessor      = 
| successor        = 
| foundation       = {{Start date|1989|11}}
| founders         = 
| defunct          = 
| location_city    = [[Summit, New Jersey]]
| location_country = United States
| locations        = 3
| area_served      = 
| key_people       = {{unbulleted list|[[Roel Pieper]]|Michael J. DeFazio|Larry Dooling}}
| industry         = {{unbulleted list|[[Software product]]s|[[Information technology consulting]]}}
| products         = {{unbulleted list|Operating systems|transaction monitors|C++ language products}}
| production       = 
| services         = 
| revenue          = $100 million (1991, equivalent to ${{Formatprice| {{Inflation|US|100000000|1991|r=-6}} }} today)
| operating_income = 
| net_income       = 
| aum              = 
| assets           = 
| equity           = 
| owner            = 
| num_employees    = 500 (1991)
| parent           = 
| divisions        = {{unbulleted list|UNIX System V Software|Open Solutions Software}}
| subsid           = 
| homepage         = 
| footnotes        = 
| brands           = 
}}
'''Unix System Laboratories''' ('''USL'''), sometimes written '''UNIX System Laboratories''' to follow relevant trademark guidelines of the time, was an American software laboratory and product development company that existed from 1989 through 1993.  At first wholly, and then majority, owned by [[AT&T Corporation|AT&T]], it was responsible for the development and maintenance of one of the main branches of the [[Unix]] [[operating system]], the [[SVR4|UNIX System V Release 4]] source code product.  Through [[Univel]], a partnership with [[Novell]], it was also responsible for the development and production of the [[UnixWare]] packaged operating system for [[IA-32|Intel architecture]].  In addition it developed [[Tuxedo (software)|Tuxedo]], a [[Transaction processing system|transaction processing monitor]], and was responsible for certain products related to the [[C++ programming language]].  USL was based in [[Summit, New Jersey]], and its CEOs were Larry Dooling followed by [[Roel Pieper]].

Created from earlier AT&T entities, USL was, as industry writer Christopher Negus has observed, the culmination of AT&T's long involvement in Unix, "a jewel that couldn't quite find a home or a way to make a profit."<ref name="negus"/> USL was sold to Novell in 1993.