Summarize the following court judgment. Civil Appeal No. 317 of 1984. From the Judgment and Order dated 10.1.80 of the Bombay High Court in Special Civil Application No. 1471/75. P.H. Parekh for the appellants. U.R. Lalit	 B.P. Maheshwari and R.S. Rana for the respondents. The Judgment of the Court was delivered by KANIA	 J. This is an appeal against the judgment of a Division Bench of the Bombay High Court delivered on January 10	 1980. The appellants before us are the Kalyan Municipal Council (referred to 834 hereinafter as 'the Municipal Council ')	 its Chief officer and the State of Maharashtra respectively. Respondent No. 1 is a Private Limited Company and is the owner of an industrial undertaking within the limits of the Municipal Council. We propose to refer to respondent No. 1 as 'the Company '. The relevant facts lie within a narrow compass and there is no dispute regarding the same. Property Tax was levied by the Municipal Council on the immovable properties of the Company within the territorial limits of the Municipal Council in respect of the years 1970 71	 1971 72 and 1972 73. In September	 1973	 the Municipal Council claimed that it had detected certain new construction and alterations in the existing construction belonging to the Company and a report to that effect was made to the Standing Committee. A proposal was submitted to the Standing Committee to increase the property tax in respect of the said immovable property from 1.4.70 to 31.3.74. On October 3	 1973	 the Standing Committee passed a resolution increasing the rateable value of the said immovable property of the Company from 1.4.70 to 31.3.74. After serving a notice on the Company as required under the provisions of Section 123(1) of the Maharashtra Municipalities Act (referred to hereinafter as the 'said Act ')	 and hearing the objections filed by the Company against the proposed increase	 a demand notice was issued on the Company on January 9	 1975 demanding an amount of Rs.51	626.69 and an appropriate amount of Educational Cess and additional Health Tax. This notice of demand was challenged by the Company by way of Special Civil Application No. 147 of 1975 before the High Court of Judicature at Bombay. The Division Bench of the Bombay High Court which decided the said Special Civil Application held that the case was covered by the decision of a Full Bench of the Bombay High Court in Sholapur Municipal Corporation vs Ramchandra Ramappa Madgundi	 [1972] 74 Bombay Law Reporter	 p. 469. The Division Bench of the Bombay High Court in the impugned judgment has pointed out that there was no dispute that a notice dated November 17	 1973	 being the notice as contemplated by Section 123(1) of the said Act was issued to the Company for amending the assessment list. This notice was served after 17th November	 1973. After analysing the provisions of Section 123 of the said Act and following the aforesaid decision of the Full Bench	 the Division Bench took the view that alteration made in the assessment list after following the procedure under Section 123(1) of the said Act does not become effective for any period prior to the commencement of the official year in which the alteration in the assessment list is made and the Municipality is not entitled to levy tax for an official year or 835 any part thereof which is already expired. The Division Bench pointed out in the present case the alteration in the assessment list was made after 31st March	 1974 and before 31st March	 1975. In view of this the said alteration could not have the effect of increasing the assessment for any year prior to the year commencing from 1st April	 1974. It is the correctness of this decision	 which is sought to be assailed before us in this appeal. Since the decision under appeal is based mainly on the said decision of a Full Bench in the case of Sholapur Municipal Corporation vs Ramchandra Ramappa Madgundi (supra)	 we may briefly refer to the said decision. That decision was based on the provisions of the Bombay Municipal Boroughs Act	 1925	 but the ratio of the decision applies to the case before us	 because the relevant provisions of the Bombay Municipal Borough Act and the said Act are in pari materia. As far as the question raised before us is concerned	 the provisions of Section 82	 Sub section (3) of the Bombay Municipal Boroughs Act are in pari materia with the provisions of Section 123(3) of the said Act. The Full Bench of the Bombay High Court in that case came to conclusion that the alteration made	 under Section 82(3) of the Bombay Municipal Boroughs Act	 in the assessment list prepared under Section 73 of that Act does not become effective for any period prior to the commencement of the official year in which the alteration in the assessment list is made and	 therefore	 the Municipality is not entitled to levy tax for an official year or any part thereof which has already expired. It was also held that the expression "current official year" in Section 82(3) of that Act means the earliest day in the official year which is current when the amendment of the assessment list takes place	 that is to say	 the expression refers to that official year which is running at the time when the amendment is made by insertion or alteration of an entry under Section 82(1) of the Act. The submission of Mr. Parekh	 learned counsel for the appellants	 is that the aforesaid case before the Full Bench was wrongly decided and	 as the judgment under appeal follows the said decision of the Full Bench	 that judgment is also erroneous and liable to be set aside. In our view	 this contention must be negatived in view of the decision of this Court rendered by a Bench of three learned Judges in Municipal Corporation of City of Hubli vs Subha Rao Hanumatharao Prayag & Ors.	 [1976] 3 S.C.R. p. 883. A perusal of the said decision makes it clear that this Court took the view that the scheme of relevant provisions of the Bombay Municipal Boroughs Act	 1925 shows that the official year is the unit of time for the levy of property tax under 836 that Act. It was further held that the expression "current official year" in the context in which it occurs in Section 82	 Sub section (3) clearly signifies the earliest day in the official year which is current when the amendment in the assessment list takes place and that expression refers only to the official year which is running at the time when the amendment is made by insertion or alteration of an entry under sub section (1) of Section 82. Thereafter this Court goes on to point out as follows: "It would	 therefore	 seem clear	 on a combined reading of Sub sections (1) and (3) of Section 82	 that an amendment	 in order to be effective in levying tax for an official year	 must be made during the currency of the official year. This is now well settled as a result of several decisions of Bombay High Court culminating in the Full Bench decision in Sholapur Municipal Corporation vs Ramchandra (supra) and we do not see any reason to take a different view. " The aforesaid statement in the judgment of this Court clearly shows that the decision of the Full Bench of the Bombay High Court in Sholapur Municipal Corporation vs Ramchandra (supra) was approved by this Court. The decision of the aforesaid Bench of this Court is binding on us and is clearly applicable to the case before us. In that judgment this Court pointed out that once it was accepted that the process of levying the tax is complete only when the assessment list is authenticated and it is only then that the tax is levied on the ratepayers	 it is difficult to resist the conclusion that the authentication must be made within the official year. The tax	 being a tax for the official year	 must obviously be levied during the official year and since the levy of the tax is complete only when the assessment list is authenticated it must follow that the authentication must take place in the official year. Mr. Parekh urged	 although not with much conviction	 that the decision of this Court in the case of Municipal Corporation of City of Hubli vs Subha Rao Hanumatharao Prayag & Ors. (supra) can be distinguished because in that case there was no question of any additional construction or new construction being detected. In our view it is not possible to make any such distinction. The question which arose before the Court was whether an assessment list which was finalised and authenticated on July 24	 1952	 after the expiry of the official year 1951 52 on 31.3.1952	 could be regarded as a good or valid assessment list for the official year 1951 52. The entire scheme of the provisions 837 pertaining to the preparation of the assessment list and the levy of property tax under the Bombay Municipal Boroughs Act	 which is materially similar to the scheme under the said Act	 was considered and the aforesaid conclusion were arrived at. There is no substance in the contention that the said decision can be distinguished. Moreover	 with respect	 we see no reason to take a different view from the one taken in the aforesaid case. The official year is the unit of taxation as far as Municipal Property taxes are concerned and	 if the contention of Mr. Parekh is accepted	 the result would be that an assessment list could be altered at any time if the conditions set out in Section 123 of the said Act are satisfied	 with the result that there would be complete uncertainty in the field of taxation of property and the unwarry purchasers of immovable property might be put to the difficulty of having of discharge the liabilities for property taxes for years long prior to the time when they purchased the immovable property in order to save the property from being sold in recovery proceedings. In the result	 the appeal fails and is dismissed with costs. S.L. Appeal dismissed.

After levy of the property tax by the Kalyan Municipal Council ( 'the Municipal Council ') on the immovable properties of the Respondent No. 1 ( 'the company ') in respect of certain years	 the Municipal Council detected certain new construction and alterations in the existing properties of the Company	 and on October 3	 1973 a resolution was passed by the Standing Committee increasing the rateable value of the said immovable property from 1.4.70 to 31.3.74. A demand notice	 demanding additional property tax	 Educational cess and Health Tax	 was issued thereafter to the Company. The Company challenged the notice of demand before the High Court. The High Court decided in favour of the Company	 holding that alteration made in the assessment list after following the procedure under section 123(1) of the Maharashtra Municipalities Act (the 'said Act ') did not become effective for any period prior to the commencement of the official year in which the alteration in the assessment list was made and the Municipality was not entitled to levy tax for an official year or any part thereof which was already expired. This appeal was filed in this Court against that decision of the High Court. Dismissing the appeal	 the Court	 ^ HELD: The ratio of the decision of the Full Bench of the Bombay High Court in Sholapur Municipal Corporation vs Ram Chandra Ramappa Madgundi	 [1972] 74 Bombay Law Reporter 469	 upon which the judgment of the High Court impugned in this case was based	 applied to this case. The appellants contended that the said case before the Full Bench had been wrongly decided and the judgment under appeal based on that decision was also erroneous. this contention must be negatived in view of the decision of this Court in Municipal Corpora 833 tion of City of Hubli vs Subba Rao Hanumatharao Prayag & Ors. 	[1976] 3 S.C.R. p. 883	 which approved the said decision of the Full Bench of the High Court	 and which is binding on the Court and clearly applicable to this case. In that judgment	 this Court had pointed out that once it was accepted that the process of levying the tax was complete only when the assessment list was authenticated and it was only then that the tax was levied on the rate payers	 the authentication must be made within the official year. The tax	 being a tax for the official year	 must be levied during the official year and since the levy of the tax is complete only when the assessment list is authenticated	 it must follow that the authentication must take place in the official year. The official year is the unit of taxation as far as Municipal property taxes are concerned. [836D	G	837A B] If an assessment list could be altered at any time if the conditions set out in Section 123 of the said Act are satisfied	 the result would be that there would be complete uncertainty in the field of taxation of property and unwary purchasers of immovable property might be put to the difficulty of having to discharge the liabilities for property taxes for years long prior to the time when they had purchased the immovable property in order to save the property from being sold in recovery proceedings. [837B C] Sholapur Municipal Corporation vs Ramchandra Ramappa Madgundi	 [1972] 74 Bombay Law Reporter 469 and Municipal Corporation of City of Hubli vs Subha Rao Hanumatharao Prayag & Ors.	 ; 	 referred to.