N.Y. Gen. City Law § 14
The mayor of any city of the first class or the commissioner of transportation in the city of New York, may, in his discretion, grant temporary permits for the erection of booths, stands, arches, overhead passageways, or flagstaffs for the stringing of flags or banners, upon or over the sidewalks or streets of such city for the purpose of a public celebration, exposition, fair, political demonstration or any charitable or patriotic drive, function or celebration; provided, however, that no such permit shall be granted for the erection of any such structure or device which is to be used in whole or in part for business or commercial advertising purposes. No such permit shall be granted by virtue of this section without the consent of the owners of the abutting property constituting more than one-half of the foot frontage upon both sides of such street in the block formed by the nearest cross-streets on each side of such structure or erection.
N.Y. Gen. City Law § 14