Coded data for disposal on or in a surface that includes a number of coded data portions. Each coded data portion encodes an identity of an object or the like associated with the surface. In addition, each coded data portion encodes at least part of a data object so that the data object is encoded in its entirety over a number of data portions, thereby allowing the data object to be reconstructed. The data object can include digital data relating to the object, such as product information, or a digital signature of at least part of the identity.