Reversal of an Impairment Loss for Goodwill :
108. As an exception to the requirement in paragraph 98, an impairment loss recognised for goodwill should not be reversed in a subsequent period unless:
(a) the impairment loss was caused by a specific external event of an exceptional nature that is not expected to recur; and
(b) subsequent external events have occurred that reverse the effect of that event.
109. Accounting Standard (AS) 26, Intangible Assets, prohibits the recognition of internally generated goodwill. Any subsequent increase in the recoverable amount of goodwill is likely to be an increase in internally generated goodwill, unless the increase relates clearly to the reversal of the effect of a specific external event of an exceptional nature.
110. This Standard does not permit an impairment loss to be reversed for goodwill because of a change in estimates (for example, a change in the discount rate or in the amount and timing of future cash flows of the cashgenerating unit to which goodwill relates).
111. A specific external event is an event that is outside of the control of the enterprise. Examples of external events of an exceptional nature include new regulations that significantly curtail the operating activities, or decrease the profitability, of the business to which the goodwill relates.