Related Clues:

• ID since the Great Depression
• Application info, often
• 001-01-0001, for one: Abbr
• ID with a billion possibilities
• IRS digits
• Common phishing target: Abbr
• Nine digits on an I-9
• Fig. on a blue card
• Info that's often only partly revealed: Abbr
• ID on an I-9 form
• ID often used on forms
• ID whose first three numbers cannot be 666
• 111-11-1111 is not a valid one
• Job application datum: Abbr
• IRS form ID