Income Tax Act, 1961
Section 151. SANCTION FOR ISSUE OF NOTICE.
(1) In a case where an assessment under sub-section (3) of section 143 or section 147 has been made for the relevant assessment year, no notice shall be issued under section 148 by an Assessing Officer, who is below the rank of Assistant Commissioner or Deputy Commissioner unless the Joint Joint Commissioner is satisfied on the reasons recorded by such Assessing Officer that it is a fit case for the issue of such notice :
Provided that, after the expiry of four years from the end of the relevant assessment year, no such notice shall be issued unless the Chief Commissioner or Commissioner is satisfied, on the reasons recorded by the Assessing Officer aforesaid, that it is a fit case for the issue of such notice.
(2) In a case other than a case falling under sub-section (1), no notice shall be issued under section 148 by an Assessing Officer, who is below the rank of Deputy Commissioner, after the expiry of four years from the end of the relevant assessment year, unless the Joint Commissioner is satisfied, on the reasons recorded by such Assessing Officer, that it is a fit case for the issue of such notice.