N.Y. R.R. Law § 186
The corporate existence and powers of every street surface railroad corporation, which has completed a railroad upon a substantial portion of the route designated in its certificate of incorporation, or of extension, within ten years from the date of filing such certificate in the office of the department of state, and which was operating such completed portion of its railroad on the twenty-third day of March, nineteen hundred and twelve, and had operated a portion of the same continuously for a period of five years immediately preceding said date, shall continue as to the completed portion of said road only with like force and effect, as though it had in all respects complied with the provisions of law with reference to the time when it should have fully completed its road, or such extension. Every such corporation shall have the right to operate any extensions and branches of its railroad, now constructed and operated by it, which had been so constructed and operated by it, for a period of ten years immediately preceding said twenty-third day of March, nineteen hundred and twelve, with like force and effect, as though the route of such extensions and branches were designated in its certificate of incorporation.
But every such street surface railroad corporation is authorized to operate such railroad and any extensions or branches thereof, upon condition that it has heretofore obtained, or shall hereafter obtain, the consent of the local authorities having the control of that portion of the streets, avenues or highways included in such railroad, or any extension or branch thereof, to the construction and operation of the same, and also upon the condition that it has heretofore obtained or shall hereafter first obtain the consent of the owners of one-half in value of the property bounded on the portion of the streets, avenues or highways included in the route of such railroad, or any extensions or branches thereof, to the construction and operation of the same, or in case the consent of such property owners can not be obtained, the appellate division of the supreme court of the department in which such railroad or any extension or branch thereof is located, may, upon application, appoint three commissioners who shall determine, after a hearing of all the parties interested, whether such railroad ought to be constructed or operated, and their determination, confirmed by the court, may be taken in lieu of the consent of the property owners. If any street surface railroad corporation shall have made and filed a statement or statements of proposed extensions or branches embracing a line from the boundary of a city or village to the boundary of another city or village generally parallel with the route specified in its certificate of incorporation and generally distant not more than one-half mile therefrom, and shall have made and filed an agreement of consolidation with some other street surface railroad corporation formed to build a street railroad upon a route continuous or connecting with one or more of the routes described in such statement or statements of proposed extensions or branches, and thereafter there shall have been constructed and operated for a period of four years a street surface railroad from such city or village to such other city or village upon a line embraced in any such proposed extensions or branches, such consolidated corporation may relinquish and abandon any unconstructed route or unconstructed portions of route specified in the certificate of incorporation or in any statements or proposed extensions or branches of such first mentioned corporation by filing in the office of the department of state a copy of a resolution of the board of directors of such consolidated corporation certified by its president and secretary, declaring such unconstructed route or unconstructed portions of route relinquished or abandoned, and thereupon the corporate rights, powers and franchises of such consolidated corporation shall be and continue the same as though the certificate of incorporation of such constituent corporation had specified the constructed and not the unconstructed portions of such route and proposed extensions and branches. All consents given, or grants made by local authorities having the control of the portion of any street, avenue or highway included in the route of such railroad, or any extensions or branches thereof, to any such street surface railroad corporation, prior to March twenty-third, nineteen hundred and twelve, are hereby ratified and confirmed and declared valid. This section shall not apply to or affect any railroad corporation in the city of New York; nor any special grant made to or authority conferred upon any street surface railroad corporation by any law of this state; nor any litigation pending on March twenty-third, nineteen hundred and twelve; nor shall it impair rights, privileges, or franchises existing on said date of any street surface railroad corporation.
N.Y. R.R. Law § 186