The history of Toshiba before its separation in 2022 is published here.
History
2022: Approval of shareholders to allocate the company
In February 2022] Toshiba revised restructuring plans and instead of three companies decided to divide into two: Infrastructure Service Co. Device Co. and First will be responsible for infrastructure systems and solutions, digital solutions, as well as for batteries and chips Kioxia within the Device Co. business. Will develop the sector of power, semiconductors electronic devices and storage, large-capacity hard drives and analog integrated circuits. More. here
2021: Stand-alone
In mid-November 2021 Toshiba , it announced a restructuring in which the conglomerate will be divided into three separate companies: Infrastructure Service,, Device Toshiba. More. here