IC card receiving power from terminal and performing process, IC card comprises storage storing first identification information uniquely assigned to IC card, acquisition unit acquiring second identification information from terminal, first timer including first change unit whose state changes with lapse of time without power, state of first change unit changing from first initial state to final state via intermediate state, first timer outputting first signal indicative of changed state of first change unit when IC card receives power, comparison unit comparing second identification information with first identification information, determining whether second identification information and first identification information are identical, and providing first initializing signal according to at least one of determined results, and controller initializing first change unit to first initial state when receiving first initializing signal, controller further controlling IC card to make it inhibit process until state of first change unit changes to intermediate state.