[ Postponement of original gainU.K.
2(1)On the making of a claim by the investor for the purposes of this Schedule, so much of the investor’s unused qualifying expenditure on [the relevant shares] as—U.K.
(a)is specified in the claim, and
(b)does not exceed so much of the original gain as is unmatched,
shall be set against a corresponding amount of the original gain.
(2)Where an amount of qualifying expenditure on [the relevant shares] is set under this Schedule against the whole or part of the original gain—
(a)so much of that gain as is equal to that amount shall be treated as not having accrued at the accrual time; but
(b)paragraphs 4 and 5 below shall apply for determining the gain that is to be treated as accruing on the occurrence of any chargeable event in relation to any of [the relevant shares].
(3)For the purposes of this Schedule—
[(a)the investor’s qualifying expenditure on [the relevant shares] is the amount subscribed by him for the shares; and]
(b)that expenditure is unused to the extent that it has not already been set under this Schedule against the whole or any part of a chargeable gain.
(4)For the purposes of this paragraph the original gain is unmatched, in relation to any qualifying expenditure on [the relevant shares], to the extent that it has not had any other expenditure set against it under this Schedule ... .]