... incurredwhen shares of the risky asset are traded but, on the other hand, that tradingin riskless bonds is cost-free. More precisely, we assume that when the stockprice is S, buying one share incurs a ... deter-mine this least cost. In this paper, we consider two-period binomial models and show that, fora special class of claims including short call and put options, there are just four possibilities ... special class ofclaims including short call and put options there are just four possibilities sothat the least cost superreplicating portfolios can be easily calculated for suchpositions. In Section...