This subpart contains the Social Security Administration's rules for filing a claim for old-age, disability, dependents', and survivors' insurance benefits as described in subpart D of part 404. It tells what an application is, who may sign it, where and when it must be signed and filed, the period of time it is in effect and how it may be withdrawn. This subpart also explains when a written statement, request, or notice will be considered filed. Since the application form and procedures for filing a claim under this subpart are the same as those used to establish entitlement to Medicare benefits under 42 CFR part 405, persons who wish to become entitled to Medicare benefits should refer to the provisions of this subpart. Requirements concerning applications for the black lung benefits program are contained in part 410. Requirements concerning applications for the supplemental security income program are contained in part 416. Part 422 contains the requirements for applying for a social security number.