2019 merger of CBS and Viacom
The 2019 merger of CBS Corporation and Viacom was announced on August 13, 2019, and was completed on December 4, 2019. The merger of equals reunited the second incarnations of CBS Corporation and Viacom into a single company known as ViacomCBS (later renamed Paramount Global) after their separation from the first incarnation of Viacom on December 31, 2005.
Source: Wikipedia — 2019 merger of CBS and Viacom (CC BY-SA 4.0)