The Registration Act,1908
Section 49. Effect of non-registration of documents required to be registered
No document required by Section 17 or by any provision of the Transfer of Property Act,1882 to be registered shall-
(a) Affect any immovable property comprised therein, or
(b) Confer any power to adopt, or
(c) Be received as evidence of any transaction affecting such property or conferring such power; unless it has been registered:
Provided that an unregistered document affecting immovable property and required by this Act or the Transfer of Property Act,1882, to be registered may be received as evidence of a contract in a suit for specific performance under Chapter 11 of the Specific Relief Act,1877, or as evidence of part performance of a contract for the purposes of Section 53A of the Transfer of Property Act,1892, or as evidence of any collateral transaction not required to be effected by registered instrument.