(1) For the purposes of this section -
(a) 2 or more companies shall be associated companies if by themselves they would form a group of companies;
(b) a chargeable gain shall be deferred on a replacement of business assets if, by one or more claims under section 597, a chargeable gain on the disposal of those assets is treated as not accruing until the new assets within the meaning of that section cease to be used for the purpose of a trade carried on by the company making the claim;
(c) an asset acquired by the chargeable company shall be treated as the same as an asset owned at a later time by that company or an associated company if the value of the second asset is derived in whole or in part from the first asset, and in particular where the second asset is a freehold, and the first asset was a leasehold and the lessee has acquired the reversion;
(d) references to a company ceasing to be a member of a group of companies shall not apply to cases where a company ceases to be a member
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