Description Gas in the minivan? Check. Directions to the mall? Check. Shopping list? Check. Checkbook? TeleCheck! The company helps all those merchants process all those checks that all those consumers love to write (or submit electronically). Its services include check acceptance, guarantee, and verification for transactions that occur at the point of sale, over the Internet, and over the phone. TeleCheck's clients include financial institutions, utilities, grocery and big-box stores, and other retailers. The company is owned by First Data, one of the largest credit-card transaction processors in the US.