If an investor expects the price of an underlying instrument to rise within a certain time frame, he will purchase a call warrant that grants him the right to acquire a particular quantity of the underlying instrument at an agreed-upon price, either at any time during the exercise period (American-style) or on the expiration date (European-style). The call writer is obligated to deliver the underlying instrument at this price, and in return receives a premium from the buyer. However, most warrants are settled in cash rather than through the physical delivery of the underlying instrument.