the Municipal Council is collecting the taxes, it does not mean that the Municipal Council has acquiesced or waived the right to initiate the action for removal of unauthorised construction. That apart, the NOCs issued by the Municipal Council also show that they were without prejudice and subject to the right of the Municipal Council to take appropriate action in respect of the illegal construction. Thus, the contention based on the structures being assessed to tax, to my mind, cannot be accepted. The submission made on behalf of the petitioner/s based on Section 184(21) of the Act, also cannot be accepted for more reasons that one. Firstly, this contention, specifically with reference to Section 184(21) of the Act, was not raised either before the Municipal Council or before the Tribunal and is raised for the first time before this Court. That apart, this Court has in the case of Sidharam Yengandul Vs. State of Maharashtra , [2006 Law Suit (Bom) 1447], inter alia , held in para 6 of the judgment that once it is proved that the structure is unauthorised, the mere fact that the structure is assessed to property tax, would not have the effect of deemed regularisation or the structure being treated as authorised.