confuse, not necessary, see how GC say:

来源: 于 2006-07-27 18:07:25 [旧帖] [给我悄悄话] 本文已被阅读：次

in the back of the GC: "The person indentified by this card is authorized to work and reside in he U.S."

SSN: Valide to work only with DHS (INS) authorization.