For the purposes of the Capital Gains Tax Acts -
(a) references to a disposal of an asset include, except where the context otherwise requires, references to a part disposal of an asset, and
(b) there shall be a part disposal of an asset where an interest or right in or over the asset is created by the disposal, as well as where it subsists before the disposal, and, generally, there shall be a part disposal of an asset where, on a person making a disposal, any description of property derived from the asset remains undisposed of.