The reservation provided for in article 49 provides for a derogation from the above-mentioned rule and provides that an unregistered document which relates to immovable property and which otherwise must be registered either under the registration law or under the TPA may be obtained as evidence of a contract in a legal action for a given performance or as proof of a security transaction. In KB Saha & Sons (P) Ltd v. Development Consultant Ltd [(2008) 8 SCC 564], the Supreme Court held that a mandatory registration document, if not registered, could only be considered in an appeal for certain services as proof that a contract was concluded between two parties and that this unregistered document could not be read as proof of the content of the contract. Therefore, if a document is inadmissible in the absence of registration as evidence, none of its provisions can be admitted as evidence. Q: What if we (the lender) have agreed to modify a mortgage but are unable to obtain the agreement of the following means of charge (necessary to register the modification agreement)? In this scenario, after the holder of the registered mortgage has sold the property and recovered all debts due, the excess would be made available to other secured creditors, such as the holder of an unregistered mortgage. It is increasingly common for mezzanine lenders to accept an unregistered mortgage as collateral for a loan. While an unregistered mortgage gives priority to the lender over the borrower`s unsecured creditors, an unregistered mortgage does not give a lender the same rights or benefits as a registered mortgage. The Constitutional Court explained the judicial route available as follows. The unreg registered creditor would not be able to claim repayment under the illegal agreement, but through an action for unjustified enrichment. .