Northern Territory Consolidated Acts16. Multiple instruments relating to a single transaction
(1) If 2 or more instruments together relate to the same transaction, and both or all instruments are required to give effect to the transaction, the instruments must be treated as a single instrument executed at the time when the instruments became legally effective.
Example
If a conveyance consists of a written offer followed by a written acceptance, both instruments would be treated as a single instrument of conveyance taking effect on the date of the acceptance.
(2) If one such instrument is duly stamped with the duty applicable to the transaction as a whole, another instrument relating to the same transaction and referring to the duly stamped instrument, will also be regarded as duly stamped.