When a foreign investment bank purchases Korea Treasury Bonds (KTBs), it is naturally exposed to country risk specific to Korea such as nuclear threats from North Korea or a downgrade in sovereign credit rating. Accordingly, the foreign investment bank needs to hedge such country risk. Credit default swap (CDS) contract is an efficient hedging device because the foreign investment bank can recover the par values of KTBs even in the event of sovereign default. Recently, some foreign investment banks operating in Korea asked Korean financial institutions to be protection sellers of Korean sovereign CDSs. In return for this credit protection, the foreign investment banks offered to pay a fixed interest rate denominated in Korean currency (KRW) every three months. This structured swap, commonly referred to KTB swap, is a means of riskless arbitrage from the viewpoint of Korean financial institutions because Korea Treasury Bonds will never default unless there is a risk of an all-out war. KTB swap exploits anomalous phenomenon in which KTB rates are higher than CRS rates. We examine the hedge structure from the viewpoint of issuers of KTB swap, and also analyze incentives of investments from the viewpoint of investors.