20 C.F.R. § 416.983

How we evaluate statutory blindness.

            We will find that you are blind if you are
            statutorily blind
             within the meaning of § 416.981. For us to find that you are statutorily blind, it is not necessary—

        (a) That your blindness meet the duration requirement; or

        (b) That you be unable to do any substantial gainful activity.

Official source