(a) " property derived from the deceased" means any property which was the subject- matter of a disposition made by the deceased, either by himself alone or in concert or by arrangement with any other person, 1[ notwithstanding that the disposition was made for full consideration] in money or money' s worth paid to him for his own use or benefit, or which represented any of the subject- matter of such a disposition, whether directly or indirectly, and whether by virtue of one or more intermediate dispositions and whether any such intermediate disposition was or was not for full or partial consideration: Provided that where the first- mentioned disposition was for full consideration in money or money' s worth paid to the deceased for his own use or benefit and it is proved to the satisfaction of the Controller that the disposition was not part of associated operations which included--

(a) a disposition by the deceased, either by himself alone or in concert or by arrangement with any other person, otherwise than for full consideration in money or money' s worth paid to the deceased for his own use or benefit, or

(b) a disposition by any other person operating to reduce the value of the property of the deceased; then, in considering whether estate duty should be charged the said first mentioned disposition shall be left out of account as if this provision did not apply in relation to it;

(b) " disposition" includes any trust, covenant, agreement or arrangement; and

(c) " subject- matter" includes, in relation to any disposition, any annual or periodical payment made or payable under or by virtue of the disposition.