Michael “Bambang” Hartono (Oei Hwie Siong) inherited his father’s (Oei Wie Gwan) clove cigarette business Djarum, along with his brother Robert Budi, when he passed away in 1963. Michael studied economics and business at Diponegoro University, returning to Kudos when his father died. The kretek business, had been bought by their father in 1951, and though it had grown, the factory burnt down shortly before they inherited it.

They rebuilt it and expanded the business, completing their first exports less than a decade later as well as introducing new products and brands. They extended their interest into industries outside cigarettes, namely palm oil and communication towers, and the electronics brand Polytron.

At the turn of the century they entered the world of finance, and though their cigarette business is one of the biggest in Indonesia with around a fifth of the market, it is from their banking endeavors that they have made their real fortune. Michael has recently moved into the real estate and property business.