Section 197 in The Indian Contract Act, 1872
Title: Ratification may be expressed or implied.
Ratification may be expressed or may be implied in the conduct of the person on whose behalf the acts are done.
(a) A, without authority, buys goods for B. Afterwards B sells them to C on his own account; B's conduct implies a ratification of the purchase made for him by A.
(b) A, without B's authority, lends B's money to C. Afterwards B accepts interest on the money from C. B's conduct implies a ratification of the loan.
Title: Knowledge requisite for valid ratification.
No valid ratification can be made by a person whose knowledge of the facts of the case is materially defective.
Title: Effect of ratifying unauthorized act forming part of a transaction.
A person ratifying any unauthorized act done on his behalf ratifies the whole of the transaction of which such act formed a part.
Title: Ratification of unauthorized act cannot injure third person.
An act done by one person on behalf of another, without such other persons authority, which, if done with authority, would have the effect of subjecting a third person to damages, or of terminating any right or interest of a third person, cannot, by ratification, be made to have such effect.
(a) A, not being authorized thereto by B, demands, on behalf of B, the delivery of a chattel, the property of B, from C, who is in possession of it. This demand cannot be ratified by B, so as to make C liable for damages for his refusal to deliver.
(b) A holds a lease from B, terminable on three months' notice. C, an unauthorized person, gives notice of termination to A. The notice cannot be ratified by B, so as to be binding on A.
Title: Termination of agency.
An agency is terminated by the principal revoking his authority; or by the agent renouncing the business of the agency; or by the business of the agency being completed; or by either the principal or agent dying or becoming of unsound mind; or by the principal being adjudicated an insolvent under the provisions of any Act for the time being in force for the relief of insolvent debtors.