Signature Requirements for USCIS Forms Applicants and petitioners have to sign their respective USCIS applications and petitions. The signature must be original. Parents and legal guardians can sign on behalf of their children under age 14. Legal guardians can sign for applicants who are incompetent to sign. Under such circumstances, the USCIS application package should … Continue reading Signing, Expediting and E-filing the USCIS Application