Section 4(1)(a) in The Kerala Buildings (Lease and Rent control) Act, 1965
(a)Every landlord may within fifteen days before completion and shall, within fifteen days after the construction or re-construction of a building intended to be let our or after a building becomes vacant by his ceasing to occupy it, or by the termination of a tenancy, or by release from requisition by the Government or any other competent authority, give notice of the availability or vacancy in writing to the Accommodation Controller. Every tenant shall within fifteen days of his vacating a building occupied by him give notice of the same in writing to the Accommodation Controller;