JUDGMENT Barin Ghosh, J.: This writ petition is by four petitioners. The petitioners are challenging the decision of the respondent Corporation to levy conservancy charges at the rates of Rs. 8,000/- and Rs. 12,000/- for large premises let out for ceremonial functions having open space including garden exceeding 1000 sq. ft. and 2,500 sq. ft. respectively. In paragraphs 2, 3, 4 and 5 of the petition, the petitioners have alleged as follows: “2. your petitioner No.1 is in lawful occupation of a portion of premises No. 24, Camac Street, Kolkata 700 017 and is entitled to hire out and let out the same, inter alia, for the purpose of holding functions. 3. Your petitioner No.2 is one of the co-owners of premises No. 4A, Short Street, Kolkata 700 016 and is entitled to hire out and let out the same, inter alia, for the purpose of holding functions. 4. Your petitioner No.3 is the owner of premises No. 38, Ballygunge Park, Kolkata 700 019 and is entitled to hire out and let out the same, inter alia, for the purpose of holding functions. 5. Your petitioner No.4 is the owner of premises No. 13/1, Ballygunge Park, Kolkata 700 019 and is entitled to hire out and let out the same, inter alia, for the purpose of holding functions." 2. In paragraph 6 of the petition it is the contention of the petitioners that in view of paucity of open space in and around Kolkata, many residents of Kolkata are compelled to hold various ceremonial and other functions in residential houses which are partially and occasionally let out for such purposes and that the petitioners occasionally let out portions of their respective properties temporarily and on daily basis for holding ceremonial functions and for other purposes. Although it has not been stated in the petition but it has been admitted at the bar that the properties, which the petitioners are letting out, were erected on the basis of sanctions accorded by the Calcutta Municipal Corporation for erecting residential buildings. In paragraph 7 of the petition it has been stated that the petitioners are letting out the properties in question for holding ceremonial functions and for other purposes including marriage ceremonies, annaprasan, sradh ceremonies, small functions, which include holding religious discourses, social and charitable functions, small get-together, etc. In paragraph 7 of the petition it has been stated that the petitioners are letting out the properties in question for holding ceremonial functions and for other purposes including marriage ceremonies, annaprasan, sradh ceremonies, small functions, which include holding religious discourses, social and charitable functions, small get-together, etc. It has been stated that the properties though are large with large open spaces, yet on many occassions small portions of the same are used by various hirers for holding small functions because of the convenient locations of the properties and for such occasions reduced charges are collected by the petitioners. It is the case of the petitioners in paragraph 8 of the petition that the municipal taxes of the properties in question are equivalent to 60 per cent of the national income calculated on the basis of 72 days of commercial use in a year. It is the case of the petitioners in the petition that although it is the obligation of the respondent Corporation to collect, remove and dispose of solid waste and for that matter the Corporation though is entitled to levy reasonable costs incurred for removal of such waste or rubbish, the impugned claim is unreasonable. 3. Before one can challenge such a claim he must demonstrate that he has locus standi to challenge the same. In other words he must demonstrate first that he is otherwise entitled to use the property in question in the manner he is using the same and then he can contend that by reason of such use the waste that has accumulated is required to be removed at a reasonable cost to be paid by him and that the impugned claim is unreasonable. 4. Chapter 22 of the Calcutta Municipal Corporation Act, 1980 deals with buildings. The said chapter covers sections 390 to 415 of the Act. Sub-section (1) of section 390 of the Act defies the expression “to erect a building”. Subsection (2) of the said section defines the expressions “occupancy” or “use-group”. Sub-section (2) of section 390 of the Act is as follows: "(2). 'Occupancy' or 'use group' means the principal occupancy for which a building or a part of a building is used or intended to be used. For the purpose of classification of a building according to occupancy, an occupancy shall be deemed to include subsidiary occupancies which are contingent upon it. 'Occupancy' or 'use group' means the principal occupancy for which a building or a part of a building is used or intended to be used. For the purpose of classification of a building according to occupancy, an occupancy shall be deemed to include subsidiary occupancies which are contingent upon it. Building with mixed occupancies shall mean those buildings in which more than one occupancy are present in different portions thereof. For the purpose of classification of a building according to occupancy, an occupancy shall be deemed to include subsidiary occupancies which are contingent upon it. Building with mixed occupancies shall mean those buildings in which more than one occupancy are present in different portions thereof. The occupancy classification shall, unless, otherwise spelt out in any development plan under any law in force for the time being, include:- (a) residential buildings, that is to say, any building in which sleeping accommodation is provided for normal residential purposes with or without cooking facility or dining facility or both; such building shall include one or two or multi-family dwellings, hostels, apartment houses and flats, and private garages; (b) educational buildings, that is to say, any building used for school, college or day-care purposes involving assembly for instruction, education or recreation incidental to educational buildings; (c) institutional buildings, that is to say, any building or part thereof ordinarily providing sleeping accommodation for occupants and use for the purposes of medical or other treatment or care of persons suffering from physical or mental illness, disease or infirmity, care of infants, convalescences or aged persons and for penal or correctional detention in which the liberty of the inmates is restricted; such buildings shall include hospitals, clinics, dispensaries, sanatoria, custodial institutions and penal institutions like jails, prisons, mental hospitals and reformatories; (d) assembly buildings, that is to say, any building or part thereof where groups of people congregate or gather for amusement or recreation or for social, religious, patriotic, civil travel, sports, and similar other purposes, such buildings shall include theatres, motion picture house, drive-in-theatres, city hall, town halls, auditoria, exhibition halls, museums, skating rinks, gymnasium, restaurants, eating houses, hotels, boarding houses, lodging or rooming houses, guest-houses, dormitories, places of worship, dance halls, club rooms, gymkhana, passenger stations and terminals of air, surface and other public transportation services, recreation piers, and stadia; (e) business buildings, that is to say, any buildings or part thereof used for transaction of business for the keeping of accounts and records or for similar purposes; such buildings shall include offices, banks, professional establishments, court houses, and libraries for the principal function of transaction of public business and keeping of books and records, and shall also include office buildings (premises) solely or principally used as an office or for office purpose. Explanation.-For the purposes of this clause,- (i) the expression 'office purpose' shall include the purpose of administration and electrical work (including telephone and telegraph operating and operating computers), and (ii) the expression 'clerical work' shall include writing, book-keeping, sorting papers, typing, filing, duplicating, punching cards or tapes, machine calculating, drawing of matter for publication, and editorial preparation of matter for publications; (f) mercantile buildings, that is to say, any building or part thereof used as shops, stores or markets for display or sale of merchandise, either wholesale or retail, or for office, storage or service facilities incidental to the sale of merchandise and located in the same building; such building shall include establishments wholly or partly engaged in wholesale trade, manufacturer's wholesale outlets (including related storage facilities), warehouses, and establishments engaged in truck transport (including truck transport booking agencies); (g) industrial buildings, that is to say, any building or structure or part thereof in which products or materials of all kinds and properties are fabricated, assembled or processed as in assembly plants; such buildings shall include laboratories, power plants, smoke houses, refineries, gas plants, mills, dairies, factories, workshops, automobile repair garages, and printing presses; (h) storage buildings, that is to say, any building or part thereof used primarily for the storage or sheltering of goods, wares or merchandise as in warehouses; building shall include cold storages, freight depots, transit sheds, store houses, public garages, hangars, truck terminals, grain elevators barns and stables; (i) hazardous building, that it to say, any building or part thereof used for the storage, handling, manufacture or processing of highly combustible or explosive materials or products which are liable to burn with extreme rapidity or which may produce poisonous fumes or explosions during storage, handling, manufacture or professing or which involve highly corrosive, toxic or noxious alkalies, acids or other liquids or chemicals producing, flames, fumes, explosions or mixtures of dust or which result in the division of matters into fine particles subject to spontaneous ignition. Sub-section (3) of section 390 of the Act defines the expression “alteration”. Sub-section (3) of section 390 of the Act defines the expression “alteration”. The said sub-section is as follows: “(3) 'alteration' means the change from one occupancy to another, or the structural change, such as the addition to any area or height, or the removal of a part of a building or the change to the structure, such as the construction of or cutting into or removal of any wall, partition, column, beam, joist, floor, or other support, or the change to or closing of any required means of ingress or egress, or the change to any fixture or equipment.” 5. Section 392 of the Act provides that no person shall erect or commence to erect any building or execute any of the works specified in section 390 of the Act except with the previous sanction of the Municipal Commissioner and in accordance with the provisions of Chapter 22 of the Act and of the rules and regulations made under the Act in relation to such erection of building or execution work. 6. The prohibition, therefore, is not to erect any building or to execute any of the works specified in section 390 of the Act and not those specified only in sub-section (1) of section 390 of the Act. The works specified in section 390 of the Act include those mentioned in sub-section (3) of section 390 of the Act, i.e., alteration, which includes change from one occupancy to another. As aforesaid, sub-section (2) of section 390 of the Act defines "occupancy" or "use group". While defining occupancy or use group sub-section (2) of section 390 of the Act says that the same shall mean the principal occupancy for which a building or a part thereof is used or intended to be used. It clarifies that an occupancy shall be deemed to include subsidiary occupancies which are contingent upon the principal occupancy .It further proceeds to say that a building may have mixed occupancy. The occupancy has been classified under several heads. While, however, classifying the same, the legislature has ordained that the occupancy of a residential building shall be the residential occupancy of the building in its entirety and not of a part of the building. Similar is the case in relation to occupancy of educational buildings. The occupancy has been classified under several heads. While, however, classifying the same, the legislature has ordained that the occupancy of a residential building shall be the residential occupancy of the building in its entirety and not of a part of the building. Similar is the case in relation to occupancy of educational buildings. In contrast the legislature has ordained that the occupancy of industrial buildings, assembly buildings, business buildings, mercantile buildings, industrial buildings, storage buildings and hazardous building, shall be if a part of the building is used as such. 7. While section 392 of the Act prohibits erection of building or execution of any work specified in section 390 of the Act, except with the previous sanction of the Municipal Commissioner, section 393 of the Act permits a person intending to erect a building to apply for sanction. While applying for sanction to erect a building it is obligatory upon the person applying, by reason of section 395 of the Act, to notify the purpose for which such building is intended to be used. If, however, more than one class of use is notified, by reason of proviso to sub-section (1) of section 395 of the Act, the application for sanction shall not be considered unless mixed occupancy as applied for is permissible under the Act or any other law in force for the time being. Section 396 of the Act ordains the Municipal Commissioner to sanction erection of a building unless the same is intended to be erected at the corner of two streets or if intended to be erected on a new street until such new street has been leveled, provided the same is proposed to be used for residential purpose. In case the proposed use of the building is other than residential building, the matter must be left with the Mayor-in-Council and such an application in terms of section 391 of the Act is required to be scrutinized by the Committee constituted by and under the said section. 8. Chapter 23 of the Act deals with Regulation of Building Uses. Sections 416 to 425 of the Act are covered by the said chapter. Section 424 of the Act, contained in chapter 23, is as follows: “424. 8. Chapter 23 of the Act deals with Regulation of Building Uses. Sections 416 to 425 of the Act are covered by the said chapter. Section 424 of the Act, contained in chapter 23, is as follows: “424. Permission in case of other non-residential uses of premises.-(1) The Municipal Commissioner may, from time to time and with the prior approval of the Mayor-in-Council, notify• such other non-residential uses of premises (including the one for an educational building or an institutional building or an assembly building or a business building or a mercantile building or an industrial building or a storage building or a hazardous building) as are not provided for in this chapter and in the case of which prior permission of the Municipal Commissioner shall be necessary, subject to the provisions of section 425, for establishing, or materially altering, or enlarging, or extending the use of, any such premises. (2) The Municipal Commissioner may refuse to give such permission in any case on the ground that such use- (a) would be objectionable by reason of the density of population in the neighbourhood, or (b) would add to the traffic constraints in the vicinity including parking spaces, for vehicles, or (c) would not conform to other predominant uses in the neighbourhood, or (d) would constitute a fire hazard, or (e) would the a nuisance to the inhabitants of the neighbourhood, or (f) in the case of hospital or clinic would be harmful to the patients due to noise or an environment which poses a health hazard, or (g) in the case of an educational building would deprive the students of playground facilities; or on any other similar ground. (3) Subject to any land use control under this Act or any other law for the time being in force, the Municipal Commissioner's decision in refusing permission under this section shall be final." 9. Therefore, when the Committee, constituted by section 391 of the Act, is considering an application for erection of a building to be used for any purpose other than residential purpose, it must take note of those factors also which have been mentioned in sub-section (2) of section 424 of the Act. Thereupon the Committee shall give its recommendation to the Mayor-in-Council. Thereupon the Committee shall give its recommendation to the Mayor-in-Council. Mayor-in-Council upon receipt of such recommendation shall decide to grant or not to grant sanction for erecting a building to be used for a purpose other than residential purpose. 10. Although the expression "mixed occupancy" has been used in the Act but the same has not been defined by the Act. In sub-rule (36a) of the Calcutta Municipal Corporation Building Rules, 1990 the expression "mixed occupancy" in relation to a building has been defined as "where no single occupancy in such building covers more than 50% of the total covered area of the building". As aforesaid, if more than one .class of use is notified in the application made by the person intending to erect, by reason of proviso to sub-section (1) of section 395 of the Act, application for sanction shall not be considered unless "mixed occupancy" as applied for is permissible under the Act or any other law in force for the time being. Similarly, as aforesaid, occupancy of a residential building shall be the residential occupancy of the building in its entirety .Therefore, if anyone applying to erect a building notifies that he wishes to use 40% of the proposed building for residential occupancy and 40% for institutional occupancy and the remaining 20% for assembly occupancy, though the same would be a mixed occupancy within the meaning of the said Rules but the same being not permissible under the Act, such an application shall not be considered at all, inasmuch as in terms of sub-section (2) of section 390 of the Act there is no concept of a residential occupancy being part of a mixed occupancy since the residential occupancy of a building as is contemplated is for such occupancy for the building in entirety and not a part thereof. Similar is the case of occupancy of educational buildings. Any other building may have mixed occupancy provided the mixture is within the framework of the said rules. 11. The underlying principal, as appears to me, is that a citizen having a land within the territories of the municipality has a recognized right to have a residential building for his residence, a part of which may also be used by others but only for the purpose of residence. 11. The underlying principal, as appears to me, is that a citizen having a land within the territories of the municipality has a recognized right to have a residential building for his residence, a part of which may also be used by others but only for the purpose of residence. A citizen, however, has no right, as a matter of course, to have a building to be constructed by him for being used as an educational building or an institutional building or an assembly building or a business building or a mercantile building or an industrial building or a storage building or a hazardous building inasmuch as such use of a building is likely to affect other citizens residing in the neighbourhood. In that view of the matter, when an application is made to erect a building for such use or such mixed use, it is obligatory upon the Mayor-in-Council, i.e., the Corporation itself to find out whether erection of a building to be used for such use or uses would or would not affect the citizens residing in the neighbourhood. 12. A reading of sub-section (2) of section 390 of the Act has convinced me that the moment a part of the residential building is proposed to be used for any other purpose, i.e:, institutional purpose, assembly purpose, business purpose, mercantile purpose, industrial purpose, storage purpose or for keeping hazardous goods, howsoever small part of the residential building is so proposed to be used, would take away the residential character of the building and the principal occupancy of such building would stand converted to either institutional or assembly or business or mercantile or industrial or storage or for storing hazardous goods, as the case may be and accordingly the proposal to erect such a building would become either a proposal to erect an institutional building or an assembly building or a business building or a mercantile building or an industrial building or a storage building or a building for storing hazardous goods. 13. 13. Therefore, at the time when sanction is accorded to erect a building either the same shall be sanctioned for being used as a residential building or as an educational building or as any other building, i.e., institutional building, assembly building, business building, mercantile building, industrial building, storage building or building to store hazardous goods or for mixed uses for institutional purpose, assembly purpose, business purpose, mercantile purpose, industrial purpose, storage purpose and for the purpose of storing hazardous goods provided less than 50% of the building is used for such purpose but not for being used as a residential or educational cum-institutional or assembly or business or mercantile or industrial or storage building. 14. Section 424 of the Act, however, permits the Municipal Commissioner with the prior approval of the Mayor-in-Council to notify non-residential use of a building. Such non-residential use may be of a residential building, for educational purpose or institutional purpose or assembly purpose or business purpose or mercantile purpose or industrial purpose or storage purpose or for the purpose of storing hazardous goods. Non-residential use of a residential building is not contemplated in Chapter 23 of the Act. Therefore, to allow such use, the Mayor-in-Council is required to give strong acceptable reasons therefor. Despite that the Municipal Commissioner has been ordained by subsection (2) of section 424 of the Act to see that such permission does not affect the rights and comforts of the citizens residing in neighbourhood of such building. 15. Section 416 of the Act is as follow: "416. Despite that the Municipal Commissioner has been ordained by subsection (2) of section 424 of the Act to see that such permission does not affect the rights and comforts of the citizens residing in neighbourhood of such building. 15. Section 416 of the Act is as follow: "416. Prohibition on change of use of building.- (1) No person shall, without any Municipal Commissioner or otherwise than in conformity with the conditions, if any, of such permission- (a) use or permit to be used for the purpose of human habitation any part of a building not originally erected or authorised to be used for such purpose; (b) change or allow the change of the use of any building for any purpose other than that specified in the sanction under section 396; (c) change or allow the change of the use of any building erected before the commencement of this Act contrary to the use for which such erection was originally sanctioned; (d) convert or allow the conversion of a tenement under a particular occupancy or use group to a tenement under another occupancy or use group: Provided that no such permission shall be given if the new occupancy or use group is otherwise than in conformity with the provisions of this Act or the rules and the regulations made thereunder or of any other law in force for the time being. (2) If, in any case, such permission is given, no change of occupancy or use group shall be allowed before any necessary alterations or provisions have been made to the satisfaction of the Municipal Commissioner and in accordance with the provisions of this Act or the rules and the regulations made thereunder or of any other law in force for the time being. (3) Any chance of use made before the commencement of this Act, except in so far as such use is permitted under section 385 of the Calcutta Municipal Act, 1951 (West Ben. Act XXXIII of 1951), shall be deemed to be an authorized change and shall be dealt with under the provisions of this Act. (3) Any chance of use made before the commencement of this Act, except in so far as such use is permitted under section 385 of the Calcutta Municipal Act, 1951 (West Ben. Act XXXIII of 1951), shall be deemed to be an authorized change and shall be dealt with under the provisions of this Act. (4) Notwithstanding any other action that may be taken against any person whether owner or occupier or both, contravening any provision of this section, the Municipal Commissioner may levy on such person in accordance with such scale as may be determined by regulations a fine not exceeding in each case rupees one hundred per square metre per month for the area under unauthorized use throughout the period during which such contravention continues. (5) The Municipal Commissioner may, if he deems fit, order that the unauthorized use be stopped forthwith: Provided that before making any such order, the Municipal Commissioner shall give a reasonable opportunity to the person affected to show cause why such order should not be made. (6) Any person aggrieved by an order of the Municipal Commissioner under sub-section (5) may, within thirty days from the date of the order, prefer an appeal against the order to the Municipal Building Tribunal appointed under section 415. (7) Where an appeal is preferred under sub-section (6), the Municipal Building Tribunal may stay the enforcement of the order on such terms, if any, and for such period as it may think fit: Provided that the fine levied under sub-section (4) shall not be waived. (8) Save as otherwise provided in this section, no court shall entertain any suit, application or other proceeding for injunction or other relief against the Municipal Commissioner to restrain him from taking any action or making any order in pursuance of the provisions of this section. (9) Every order made by the Municipal Building Tribunal on appeal and subject to such order, the order of the Municipal Commissioner under subsection (5) shall be final and conclusive. (9) Every order made by the Municipal Building Tribunal on appeal and subject to such order, the order of the Municipal Commissioner under subsection (5) shall be final and conclusive. (10) Where no appeal has been preferred against an order made under subsection (5) or where an order under that sub-section has been confirmed on appeal, whether with or without modification, the person against whom such orders has been made shall comply with the same within the period specified therein, or, as the case may be, within the period, if any, fixed by the Municipal Building Tribunal on appeal, and on the failure of such person to comply with such order within such period, the Municipal Commissioner may require any police officer or any employee of the Corporation to seal up such area after evicting all persons therefrom to prevent its further unauthorized use." 16. Thus, without obtaining written permission of the Municipal Commissioner no one can change or allow the change of the use of any building for any purpose than that specified in section 396 of the Act. A person who has erected a residential building upon obtaining sanction to erect such a building or a person entitled to use such a building is not entitled to change the use of such building to any other use. The proviso to sub-section (1) of section 416 of the Act prohibits the Municipal Commissioner to grant any permission if the new occupancy or use group is otherwise than in conformity with the provisions of the Act and the rules and regulations made thereunder or any other law in force for the time being. Since mixed occupancy in respect of a building having residential occupancy with other occupancies, is not contemplated, there is, thus, a bar in permitting occupancy of a residential building to be change to a mixed occupancy comprising of residential occupancy and any other occupancy. The same is applicable also in the case of buildings constructed as educational buildings. Since mixed occupancy in respect of a building having residential occupancy with other occupancies, is not contemplated, there is, thus, a bar in permitting occupancy of a residential building to be change to a mixed occupancy comprising of residential occupancy and any other occupancy. The same is applicable also in the case of buildings constructed as educational buildings. Therefore, unless in terms of sub-section (1) of section 424 of the Act the Municipal Commissioner with the prior approval of the Mayor-in-Council has not notified non-residential use of a residential building for educational purpose or for industrial purpose or for assembly purpose or for business purpose or for mercantile purpose, there is no power of the Municipal Commissioner to permit change of occupation of a residential building into a mixed occupation of residential occupation and any other occupation. 17. The manner the petitioners are using the properties in question squarely comes within the use group of assembly buildings inasmuch as admittedly in a part of the properties of the petitioners groups of people congregate and gather for social and religious purposes. It is not the contention of the petitioners that such use has been permitted under section 385 of the Calcutta Municipal Act, 1951, nor it is the case of the petitioners that under section 424 of the Act the Municipal Commissioner with the prior approval of the Mayor-in-Council has notified user of buildings for mixed occupancy comprising of residential occupancy and any other occupancies, and it also not the case of the petitioners that they have obtained any permission under section 416 of the Act, if the Commissioner has notified such mixed occupancy. 18. The learned counsel for the petitioners has contended that change of use must be a permanent nature. He has submitted that even the Corporation is not contending that the properties are used for assembly purpose all throughout the year, instead, the Corporation is proceeding on the basis that out of 365 days only 72 days the properties are used for assembly purpose. He further submitted that after the congregation leaves in the night, the entire property is used for residential purpose and even when the congregation is present, a large portion of property is used for residential purpose and since the assembly is not the predominant purpose, there is no change of use as such. He further submitted that after the congregation leaves in the night, the entire property is used for residential purpose and even when the congregation is present, a large portion of property is used for residential purpose and since the assembly is not the predominant purpose, there is no change of use as such. The question is not how long the properties are being used for the purpose in question. The question is of use and intention to use. If the petitioners get people to take the properties in question on rent for 365 days, they would rent out the properties for 365 days. Whether the properties are being let out for 365 days or for 72 days or for one day for assembly purpose, is not the criteria. The criteria is that the petitioners intended to let out and have let out the properties in question for assembly purpose. 19. In this connection it must be taken note of that clubrooms are included in assembly buildings. It must be noted that it is the clubrooms and not the club premises, which have been included. It is possible that in a property a few rooms are used as a club and the members of the club congregate in such rooms during a particular period of time and thereafter such rooms are used for residential purpose but still then the moment such rooms of the building are used as clubrooms, such building would be categorised as assembly building. 20. Sub-section (2) of section 390 of the Act says that "occupancy" or "use group" means principal occupancy for which a building or a part of a building is used or intended to be used. Unless a building in its entirety is used or intended to be used for residential purpose, the principal occupancy of such a building would not be residential as there is no concept of part use of a building as a residential building. The said sub-section further says that an occupancy shall be deemed to include subsidiary occupancies, which are contingent upon it. If a building is meant for residence of a family of human beings and if such a building is used for a purpose contingent upon such user, such contingent user shall be treated to be subsidiary occupancy in terms of sub-section (2) of section 390 of the Act. If a building is meant for residence of a family of human beings and if such a building is used for a purpose contingent upon such user, such contingent user shall be treated to be subsidiary occupancy in terms of sub-section (2) of section 390 of the Act. A marriage in the family residing in the same building would be such a contingent. Such contingency would be few and rare. The moment the members of such family would start using such a building for the purpose of hosting marriage ceremonies of all and sundry, who are capable of paying rent therefor, such user would no longer be subsidiary occupancy as the same would change the intend to use the building as an assembly building. While every citizen has a reciprocal obligation to give up his comfort, to which he is otherwise entitled to in law, at times for the purpose of enabling his neighbour to discharge his family obligations, but no citizen has any obligation to do so to permit his neighbour to make profit at the cost of his inconveniences. That is how subsidiary occupancies are to be understood. 21. The learned counsel for the petitioners submitted by referring to section 435 of the Act that there is a prohibition upon any person to use or permitted to be used any premises for any of the non-residential purposes mentioned in schedule V to the Act without or otherwise than in conformity with the terms of a municipal licence granted by the Municipal Commissioner. The learned counsel submitted that schedule V of the Act does not include letting out of a premises for the purposes for which the properties in question are being let out by the petitioners. The learned counsel thus submitted that when no licence is required to use the properties in question for the purposes the same are being used, such a user is permissible. 22. Section 435 of the Act is in Chapter 25 of the Act, which deals with Municipal Licences. According to my reading even if a building has been erected with the intention to use the same as a business building that would not permit the owner or the occupier of the building to house a bank thereat unless he has obtained a licence under section 435 of the Act. According to my reading even if a building has been erected with the intention to use the same as a business building that would not permit the owner or the occupier of the building to house a bank thereat unless he has obtained a licence under section 435 of the Act. Obtaining of licence for such purpose has nothing to do with change of user of the building. 23. Section 421 of the Act, which is under Chapter 23 of the Act, which chapter provides regulation of building uses, says that no person shall without written permission of the Municipal Commissioner or otherwise than in conformity with the conditions of such permission use or permit to be used or materially alter;, enlarge or extend the use of any premises for the purpose of letting out the same to any person for performance of any sacred thread, marriage, annaprasan or sradh ceremony or marriage or death anniversary or similar other ceremony. It thus makes it absolutely clear that even the owners of the assembly buildings if intend to let out or in fact let out to any person such a building or part thereof for performance of any sacred thread, marriage, annaprasan or sradh ceremony or marriage or death anniversary or similar other ceremony, they are required to obtain permission of the Municipal Commissioner. No such permission, however, will be necessary if an assembly building is used as a city hall, as a town hall, as a auditorium or as an exhibition hall, museum, skating rinks, gymnasium etc. It thus makes it abundantly clear that despite having had obtained permission to construct an assembly building unless the written permission is had of the Municipal Commissioner, the person entitled to use the building cannot let out the same for the purpose of performance of any sacred thread, marriage, annaprasan or sradh ceremony or marriage or death anniversary or other similar ceremony. Again the underlying principal is that no person at the cost of comfort of his neighbours can use a building constructed within the territory of the Corporation for profit and accordingly such permission shall be granted only when it can be ensured that a permission to do so would not cause inconvenience and discomfort to the people living in the neighbourhood. 24. Assuming on a road there are 7 properties side by side. 24. Assuming on a road there are 7 properties side by side. Each of them contains a residential building with large open space. If the middle building is used exclusively for residential purpose and the remaining 6 buildings are used in the manner the petitioners are using their properties, can anyone imagine the misery that the owner of the middle building, who is using his property for the purpose for which he had been permitted by law to use the same, would suffer? Because those 6 owners are using their properties in a manner, which is not permissible by law, to make profit, the person who is using his property for the purpose for which he has been permitted to use the same by law, would suffer? That is what is not permissible in a society, which is ruled by law. 25. It is true that while assessing the annual value of the properties of the petitioners 72 days' letting out value at the rate at which the petitioners are letting out the properties in question, are being taken into account but then that is for assessment purpose, for which purpose it is obligatory upon the respondent Corporation to take into account the reasonable letting out value, but then that cannot be considered to be a permission to use the properties in question in the manner the petitioners are using the same inasmuch as for the reasons aforesaid it is at present beyond the competence of the Commissioner to grant any such permission. 26. For the reasons aforesaid I find that the petitioners have no locus standi to even question the reasonableness of the conservancy charges, being the subject matter of the writ petition, and accordingly I dismiss this writ petition. It would be open to the writ petitioners to take appropriate steps to challenge the conservancy charges as and when they would have permission to use their properties as assembly buildings and with that they shall have permission to let out the same for performance of any sacred thread, marriage, annaprasan or sradh ceremony or marriage or death anniversary or similar other ceremony, which permission none of the petitioners has at present. 27. 27. Although I have dismissed this writ petition but having regard to the fact that in the heart of the city and at a stone's throw distance from the Head Office of the respondent Corporation four large buildings are used in a manner, which is inconsistent with the provisions of the Act, I direct the Municipal Commissioner to publish a report in such newspaper or papers, as it may deem fit to him, within 3 months from today as to how many other similar buildings have indulged in similar practices and what steps the Corporation has taken to stop such practices. 28. There shall, however, be no order as to costs. 29. Let xeroxed certified copy of this judgment, if applied for, be handed over to the learned advocates for the parties on the usual undertaking. Writ petition dismissed.