(1) This section shall apply where one company (in this section referred to as "the first company") has a holding in another company (in this section referred to as "the second company") and the following conditions are fulfilled -
(a) that the holding amounts to, or is an ingredient in a holding amounting to, 10 per cent of all holdings of the same class in the second company,
(b) that the first company is not a dealing company in relation to the holding,
(c) that a distribution is or has been made on or after the 6th day of April, 1974, to the first company in respect of the holding, and
(d) that the effect of the distribution is that the value of the holding is or has been materially reduced.
(a) Where this section applies in relation to a holding, section 621 shall apply in relation to any disposal of any shares or securities comprised in the holding, whether the disposal is by the first company or by any other company to which the holding is transferred by a transfer to which
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