USCIS wants you to know that Green Cards (also known as Permanent Resident Cards) do not always include the holder’s signature. In limited cases, USCIS may waive the signature requirement for certain people, such as children under the age of consent or individuals who are physically unable to provide a signature.
Since February 2015, USCIS has been waiving the signature requirement for people entering the United States for the first time as lawful permanent residents after obtaining an immigrant visa abroad from a U.S. Embassy or consulate.