https://en.m.wikipedia.org/wiki/OS/2 https://en.m.wikipedia.org/wiki/OS/2 : As a result of a feud between the two companies over how to position OS/2 relative

https://en.m.wikipedia.org/wiki/OS/2 https://en.m.wikipedia.org/wiki/OS/2 : As a result of a feud between the two companies over how to position OS/2 relative to Microsoft's new Windows 3.1 operating environment, the two companies severed the relationship in 1992 and OS/2 development fell to IBM exclusively. https://en.m.wikipedia.org/wiki/Windows_NT https://en.m.wikipedia.org/wiki/Windows_NT : Windows 3.0 was eventually so successful that Microsoft decided to change the primary application programming interface for the still unreleased NT OS/2 (as it was then known) from an extended OS/2 API to an extended Windows API. This decision caused tension between Microsoft and IBM and the collaboration ultimately fell apart.