Missouri-based Commerce Bank is beefing up its promotion to encourage customers to sign for their debit card purchases instead of using the PIN. Now in its fifth year, the “Skip the PIN, Sign and Win” sweepstakes will offer three $10,000 bonus prizes. Through October, Commerce Bank is selecting a $1,000 winner every week with a final grand prize of $25,000 to be awarded after the end of the year. Now, Commerce is adding a $10,000 bonus prize at the end of March, June and September. The sweepstakes applies to holders of the “Commerce Bank VISA Check Card,” “ATM Plus Card,” “Platinum Check Card,” “CommerceOptions Check Card,” and “Business Check Card.” Cardholders are automatically entered into the contest each time they use their check card and sign for their purchase rather than enter their Personal Identification Number (PIN).