| Abstract: |
| Vulnerable options of a European and American style with a possible occurrence of an exogenous termination are studied under market incompleteness in a hazard process setup. It is proven that the reduced upper price of a vulnerable European option coincides with the unique price of an American option with a properly defined payoff and holder`s exercise times constrained to the random set given by the right support of the hazard process. For a vulnerable American option, it is shown that the reduced upper price equals the price of a specific American option with unrestricted exercise times, whereas the reduced lower price coincides with the price of a particular game option in which the issuer`s exercise times are constrained to the above-mentioned random set. |
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