Permanent Account Number compliance links PAN allotment, Aadhaar linkage, quotation duties, and restrictions on multiple PANs. Every person who meets specified income, business, return-filing, or prescribed-transaction conditions must apply for allotment of a Permanent Account Number within the prescribed time, and a person not covered may still apply and receive PAN on application. The number must be quoted in returns, correspondence, and challans, and changes in address or business particulars must be intimated. The section also links PAN with Aadhaar, requires no person to hold more than one PAN, and authorises prescribed rules and notifications for applications, authentication, transaction documents, and exemptions.