This case study investigates the KIKO currency option that has been a social issue in recent years among developing countries, especially Korea, where the financial derivatives market is in a state of rapid growth. The forward transaction which becomes a basis of derivatives is intended to hedge risks that may be caused by a future change in asset prices. Although it originates from a simple form of agricultural transactions, there currently exists a variety of derivatives in more sophisticated forms. In the Korean agricultural industry, the need to use such derivatives is great, as there is a huge risk of price fluctuation in agricultural products due to frequent adverse weather. In addition, many developing countries with export-led industrial structures similar to Korea’s, of necessity must resort to currency hedging as a method of reducing relevant risk. However, in most cases, the lack of understanding about financial derivatives results in an inappropriate application of these derivatives. The KIKO in this study represents such cases. Since 2007, KIKO has been sold in Korea to many small- and medium-sized export companies for the purpose of currency hedging when the exchange rate between the Korean won and the U.S. dollar was in a downward spiral. The main focus of this study is a case which is most representative of KIKO. As inflation rapidly increased during the financial crisis in the U.S. at the end of 2007, derivatives became a hot issue in the courts rather than in the financial markets. This case study investigates what KIKO and the fierce legal debates over it imply, from the perspective of the option of value evaluation in order to suggest not only a direction in which companies can utilize financial derivatives, but also a roadmap for the future derivatives market.