Stamp Act (2 of 1899) , S.28(3), Sch.I, Art.23— Scope - Agreement to sell flat by its allottee to petitioner - Sale-deed by Delhi Development Authority in favour of allottee not executed - DDA granting petitioner's application for reversionary interest in land underneath the flat in his favour - Consideration fixed at Rs. 10,000/- Stamp duty on conveyance between DDA and petitioner - Payable only on Rs. 10,000/- Consideration for sale of flat by allottee cannot be included. In the instant case a flat was allotted by a Co-op. Housing Society, to the allottees jointly the allottees entered into an agreement with the petitioner whereby they agreed to sell their rights in the flat to the latter for a consideration of Rs. 5,51,000/- which stands paid by the petitioner to the allottees. The allottees applied to the Delhi Development Authority for converting lease-hold tenure of the flat into free-hold. The DDA sent unsigned and unexecuted conveyance deed forms to the attorney and also informed him that his request has been accepted and was required to get the unsigned and unexecuted conveyance deed forms stamped from the office of the Collector of stamps. Copy of the deed, inter alia, states that the allottees applied to the DDA for grant of reversionary interest of the DDA in the land underneath the flat to the petitioner and the DDA agreed to convey ....