Section 42 | Part disposals.

(1)Where a person disposes of an interest or right in or over an asset, and generally wherever on the disposal of an asset any description of property derived from that asset remains undisposed of, the sums which under paragraphs (a) and (b) of section 38(1) are attributable to the asset shall, both for the purposes of the computation of the gain accruing on the disposal and for the purpose of applying this Part in relation to the property which remains undisposed of, be apportioned.

(2)The apportionment shall be made by reference—

(a)to the amount or value of the consideration for the disposal on the one hand (call that amount or value A), and

(b)to the market value of the property which remains undisposed of on the other hand (call that market value B),

and accordingly the fraction of the said sums allowable as a deduction in the computation of the gain accruing on the disposal shall be—and the remainder shall be attributed to the property which remains undisposed of.

(3)Any apportionment to be made in pursuance of this section shall be made before operating the provisions of section 41 and if, after a part disposal, there is a subsequent disposal of an asset the capital allowances or renewals allowances to be taken into account in pursuance of that section in relation to the subsequent disposal shall, subject to subsection (4) below, be those referable to the sums which under paragraphs (a) and (b) of section 38(1) are attributable to the asset whether before or after the part disposal, but those allowances shall be reduced by the amount (if any) by which the loss on the earlier disposal was restricted under the provisions of section 41.

(4)This section shall not be taken as requiring the apportionment of any expenditure which, on the facts, is wholly attributable to what is disposed of, or wholly attributable to what remains undisposed of.

(5)It is hereby declared that this section, and all other provisions for apportioning on a part disposal expenditure which is deductible in computing a gain, are to be operated before the operation of, and without regard to, section 58(1), sections 152 to 158 (but without prejudice to section 152(10)), section 171(1) or any other enactment making an adjustment to secure that neither a gain nor a loss occurs on a disposal.