Income-Tax Act (43 of 1961) , S.12A, S.12AA(3)— Registration of certificate - Power to cancel - No express provision vesting Commissioner of Income Tax (CIT) with power to cancel registration certificate granted to assessee under S. 12A till amendment made in @page-SC3561S. 12AA(3) w. e. f. 1-10-2004 - Order granting registration certificate passed by CIT is quasi judicial order - Cannot be cancelled by taking recourse to S. 21 of General Clauses Act. General Clauses Act (10 of 1897) , S.21— Misc. Appeal (Income Tax) No. 6 of 2005, D/- 14-3-2007 (MP), Reversed.(2011) 243 CTR 245 (Del); 2006 Tax LR 383 (Utr) and 2009 Tax LR 558 (All), Approved. (Para 29 30 31)