Stamp duty shall not be chargeable on any instrument which is certified to the Commissioners of Inland Revenue by the Corporation, the Post Office or any wholly owned subsidiary of either of those bodies as having been made or executed in pursuance of section 10 or Schedule 2; but no such instrument shall be deemed to be duly stamped unless it is stamped with the duty to which it would but for this subsection be liable or it has, in accordance with the provisions of section 12 of the M1Stamp Act 1891, been stamped with a particular stamp denoting that it is not chargeable with any duty or that it is duly stamped.

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