Permanent account number requirement mandates PAN be quoted by payees, deductors, buyers and sellers for tax reporting. The Finance Act, 2001 adds mandatory PAN obligations: payees must intimate PAN to deductors for sums taxed under Chapter XVIIB (with limited non-resident and temporary G.I.R. exceptions); deductors must quote payee PAN in statements, certificates and returns, subject to notification of phased dates and exemption if a nil-tax declaration under section 197A is furnished; buyers must intimate PAN to sellers under section 206C and sellers collecting tax must quote buyer PAN in prescribed certificates and returns.