(a)  if four years have elapsed from the end of the relevant assessment year, unless the case falls under clause (b) or clause (c);

(b)  if four years, but not more than six years, have elapsed from the end of the relevant assessment year unless the income chargeable to tax which has escaped assessment amounts to or is likely to amount to one lakh rupees or more for that year;

(c)  if four years, but not more than sixteen years, have elapsed from the end of the relevant assessment year unless the income in relation to any asset (including financial interest in any entity) located outside India, chargeable to tax, has escaped assessment.

Explanation.—In determining income chargeable to tax which has escaped assessment for the purposes of this sub-section, the provisions of Explanation 2 of section 147 shall apply as they apply for the purposes of that section.

(2) The provisions of sub-section (1) as to the issue of notice shall be subject to the provisions of section 151.

(3) If the person on whom a notice under section 148 is to be served is a person treated as the agent of a non-resident under section 163 and the assessment, reassessment or recomputation to be made in pursuance of the notice is to be made on him as the agent of such non-resident, the notice shall not be issued after the expiry of a period of six years from the end of the relevant assessment year.

Explanation.—For the removal of doubts, it is hereby clarified that the provisions of sub-sections (1) and (3), as amended by the Finance Act, 2012, shall also be applicable for any assessment year beginning on or before the 1st day of April, 2012.