Section 157 of Income Tax Act "Intimation of loss"
157. When, in the course of the assessment of the total income of any assessee, it is established that a loss has taken place which the assessee is entitled to have carried forward and set off under the provisions of sub-section (1) of section 72, sub-section (2) of section 73, sub-section (1) or sub-section (3) of section 74 or sub-section (3) of section 74A, the Assessing Officer shall notify to the assessee by an order in writing the amount of the loss as computed by him for the purposes of sub-section (1) of section 72, sub-section (2) of section 73, sub-section (1) or sub-section (3) of section 74 or sub-section (3) of section 74A.
158. Whenever, in respect of the assessment year commencing on the 1st day of April, 1992, or any earlier assessment year, a registered firm is assessed, or an unregistered firm is assessed under the provisions of clause (b) of section 183, the Assessing Officer shall notify to the firm by an order in writing the amount of its total income assessed and the apportionment thereof between the several partners.