Duties Act 1997

For the purposes of this Act, an instrument is taken to be first executed the first time that it is signed and sealed, or signed (as the case may be) by any party to it.

However, a contract made by acceptance of an offer contained in an instrument is taken to be first executed when the offer is accepted.

If an instrument is ineffective by reason of a failure of the necessary parties to execute it, a refund may be made of any money paid for stamping.