Where a contract between a risk management firm and a printer was silent as to the level of security required of scratch-off cards, the printer could not be liable for defective cards.The 7th U.S. Circuit Court of Appeals affirmed a decision by U.S. District Judge C.N. Clevert Jr., Eastern District of Wisconsin.Sabafon, a telephone company based in Yemen, wanted to buy cards that would provide its customers with prepaid minutes of phone use. To make these cards more attractive to its customers, Sabafon wanted to add a game …