The defining piece of evidence was a seal that was initially thought to be a simple official seal, but was later discovered to be actually a seal bearing the name of the owner of the tomb. When the seal was first revealed after it was excavated from the tomb, it was presented upside down so the Chinese character inscribed on it in seal script did not make any sense. After the error was corrected, archaeologists recognised that the Chinese character on the seal reads Huan, hence they deduced that the tomb owner was Cao Huan. Cao Huan died at the age of 57, which was rather close to the age at which the man in the tomb died.