Masterlock can provide a lock's combination based on its serial number, but this information is not public record and no customer can determine the combination based on the serial number alone. Masterlock no longer imprints serial numbers on locks for added security.
Masterlock will not provide a combination to a customer over the phone, even if the customer has a serial number. In order to receive a combination for a lock, the customer must either visit a Masterlock retailer to confirm ownership or fill out a lost combination form along with a notary witness of ownership. Masterlock provides this information as well as a secure web service for storing combinations on its official website.