A panel of judges in the Appellate Division, First Department on Wednesday heard arguments in the case of 200 Amsterdam, the Upper West Side building that has garnered substantial attention for its potential "haircut," or the removal of already-built floors at the top of the tower.

In February, New York County Supreme Court Justice W. Franc Perry ruled in favor of the plaintiffs, the Committee for Environmentally Sound Development and the Municipal Art Society of New York, which raised zoning issues relating to the building and its 55-story height. Perry ordered the New York City Department of Buildings to compel 200 Amsterdam's owner to remove floors exceeding the bulk permitted by city zoning rules.

The developer, Amsterdam Avenue Redevelopment Associates, soon appealed, arguing that Perry should not have allowed a new interpretation of city rules to apply retroactively to floors of the building already constructed.