They are and have been involved in running the fashion house Forrester Creations but the core of their business interests is the ownership and management of the international shipping company Marone Industries.
When it was revealed that Ridge Forrester was Massimo's son Ridge became Vice Chairman of the Marone Industries and added fashion house Spectra Fashions as a subsidiary but Massimo eventually sold it back to Sally Spectra.
Nick sold his stock in Marone Industries to board member George Septolino, who presumably took over as CEO.
It was revealed that this includes banking and real estate when Massimo was able to check the bank account records of Mark Maclaine to prove that Stephanie bribed him to help her fake a heart attack in order to break up Ridge's marriage to Brooke.
Mark Maclaine revealed that his apartment complex was owned by Marone Industries.