When Madras Act (XVIII of 1960) was passed, section 30 was enacted therein exempting from the operation of the Act any non-residential building, the rental value of which on the date of the commencement of that Act as entered in the tax assessment book of the municipal council or other local body exceeded Rs. 400 per mensem. This provision was amended by Madras Act (II of 1962) substituting in the place of the rental value entered in the tax assessment book, the monthly rent paid by the tenant. This exemption was removed later by Act (XI of 1964.) In between the dates of the passing of the two latter Acts, the landlords of certain premises, the respondents in this petition, filed an application before the House Rent Controller — H.R.C. No. 2942 of 1963 — for the fixation of fair rent. The tenant came to this Court contending that since the tenancy was under a contractual arrangement by means of a registered lease deed for a term of years, the House Rent Control Act could not apply to this tenancy. Apart from this general contention, it was also claimed that the monthly rental payable by the tenant was in excess of Rs. 400, so that by reason of section 30 of the Act as a