For section 4 of the principal Act, the following section shall be substituted, namely:—

"4. (1) An Aadhaar number, issued to an individual shall not be re-assigned to any other individual.

(2) An individual may voluntarily use his Aadhaar number to establish his identity, by authentication or offline verification.

(3) Every requesting entity to whom an authentication request is made by an Aadhaar number holder shall—

(a) obtain the consent of the individual before collecting his identity information for the purposes of authentication; and

(b) ensure that the identity information of an individual is only used for submission to the Central Identities Data Repository for authentication.

(4) No individual shall be denied any service for not having an Aadhaar number, unless authentication of such individual is required by a law made by Parliament."