During the 1960s and early 1970s, Kirubi worked as an Administrator at Kenatco, a government-owned transportation company. Around 1971, he began buying run-down buildings in the cities of Nairobi and Mombasa, renovating them for resale or renting them out. He also began acquiring prime land in and around Nairobi and proceeded to erect rental and other commercial properties, using loans from Kenyan financial institutions.
Holdings Kìrubi was the largest single investor in Centum Investment Company, whose stock is listed on both the
Nairobi Stock Exchange and on the
Uganda Securities Exchange. and
Nation Media Group.
Former investments At one time, Kìrubi owned 9.58 percent of
UAP Holdings, an investment and insurance conglomerate that provides investment and insurance services in the countries of Eastern and Central Africa. In 2015, he sold his shares to Old Mutual and exited the stock. In May 2020, Haco Industries sold the BIC brand (stationery, lighters and shavers) to French conglomerate Société BIC. The deal brought to an end 40 years of Haco's BIC franchise. == Philanthropy ==