For a full list of “Category” codes for Employment Authorization Document – here.
Reading the Back of the Card
1–2: C1 or C2. C1 = Resident within the United States C2= Permanent Resident commuter (Living in Canada or Mexico)
3–5: USA (issuing country, United States)
6–14: 9-digit number (A#, alien number)
15: application receipt number
16–30: immigrant case number that resulted in the approved green card. The “<” symbol represents a blank space
1-6: birth date (in YY/MM/DD format)
7: not documented, assumed to be a check digit 8: gender
9-14: expiration date (in YY/MM/DD format) 15: not documented, assumed to be a check digit 16-29: country of birth
30: not documented, assumed to be a check digit
Last name, first name, middle name, first initial of father, first initial of mother (this line is spaced with “<<” between the last name and first name). Depending on the length of the name, the father’s and mother’s initials may be omitted.