Acquisition of Westinghouse by the international consortium led by Toshiba attracted a great deal of global attention, although Toshiba concluded a secret agreement to give put options to their partners in the deal. As a result, the execution of the options by a partner gave an additional blow to the already daunted Toshiba, when Toshiba was said to suffer a huge loss through its nuclear power engineering business after the Fukushima nuclear disaster due to the Great East Japan Earthquake in 2011, which is said to have eventually triggered off Toshiba accounting scandal. In this paper, we evaluate the put options Toshiba gave to their partners and estimate how much loss Toshiba suffered from the consequences of the Fukushima nuclear disaster, in order to take a better view of Toshiba accounting scandal, through the approach of Real Options, Merton model and the Event Study.
