Financial firms will be slapped with fines amounting to 3 percent of their annual sales when responsible for a massive leak of personal data, and clients will be given an option to revoke their consent to providing their private information, the country's financial regulator said Monday. Also, financial firms will be required to delete clients' data upon termination of financial transactions during a given grace period and barred from sharing the data with their affiliates beyond a set limit, according to the Financial Services Commission (FSC).