Section 9(3)(c) in The Bombay Rents, Hotel and Lodging House Rates Control Act, 1947
(c)The increase in rent under clause (a) shall be recoverable from all tenants occupying premises in the building on the basis of the actual expenses incurred as specified in a certificate from the local authority or the architect as aforesaid, and the amount to be recovered from each tenant shall bear the same proportion as the rent payable by him in respect of his premises bears to the total amount of actual expenses together with interest as aforesaid.