Income and Corporation Taxes Act 1988

21 (1) If one or more ring fence losses are set off under section 393 against any profits of a post-commencement period, reductions are to be made in that period in accordance with this paragraph.

(2) If the company has a non-qualifying pool, the amount in the non-qualifying pool is to be reduced (but not below nil) by setting against it a sum equal to the total amount so set off.

(3) If—

(a) any of that sum remains after being so set against the amount in the non-qualifying pool, or

(b) the company does not have a non-qualifying pool,

the amount in the ring fence pool is to be reduced (but not below nil) by setting against it so much of that sum as so remains or (as the case may be) a sum equal to the total amount set off as mentioned in sub-paragraph (1).

(4) If the post-commencement period is the deemed accounting period under paragraph 3(3) beginning on 1st January 2006 (“the deemed accounting period”), the amount of the profits of the deemed accounting period is determined as follows.

(5) The amount of the profits of the straddling period is apportioned to the deemed accounting period in proportion to the number of days in the deemed accounting period that fall in the straddling period.

(6) The apportioned amount is taken for the purposes of this paragraph to be the amount of the profits of the deemed accounting period.

(7) In this paragraph “the straddling period”, in relation to a qualifying company, means an accounting period of the company—

(a) beginning before 1st January 2006, and

(b) ending on or after that date,

disregarding paragraph 3(3).