IBM bought Red Hat in 2019 in a deal valued at approximately $34 billion.
IBM announced the acquisition in October 2018 and completed it in July 2019. Red Hat continued to operate as a distinct unit, with its leadership and open-source business serving as an important part of IBM's hybrid-cloud strategy.
Red Hat is best known for Red Hat Enterprise Linux, a commercial distribution of the Linux operating system, along with technologies such as OpenShift. IBM expected Red Hat's software and expertise to help customers run workloads across private data centers and multiple public clouds.
The transaction was an acquisition of Red Hat by IBM, not a merger of equals. It also did not mean IBM owned Linux itself: Linux remains an open-source project with contributions from many organizations and individuals.