New York Laws
Article 2 - Mechanics' Liens
11 - Service of Copy of Notice of Lien.

§ 11. Service of copy of notice of lien. Within five days before or
thirty days after filing the notice of lien, the lienor shall serve a
copy of such notice upon the owner, if a natural person, (a) by
delivering the same to him personally, or if the owner cannot be found,
to his agent or attorney, or (b) by leaving it at his last known place
of residence in the city or town in which the real property or some part
thereof is situated, with a person of suitable age and discretion, or
(c) by registered or certified mail addressed to his last known place of
residence, or (d) if such owner has no such residence in such city or
town, or cannot be found, and he has no agent or attorney, by affixing a
copy thereof conspicuously on such property, between the hours of nine
o'clock in the forenoon and four o'clock in the afternoon; if the owner
be a corporation, said service shall be made (i) by delivering such copy
to and leaving the same with the president, vice-president, secretary or
clerk to the corporation, the cashier, treasurer or a director or
managing agent thereof, personally, within the state, or (ii) if such
officer cannot be found within the state by affixing a copy thereof
conspicuously on such property between the hours of nine o'clock in the
forenoon and four o'clock in the afternoon, or (iii) by registered or
certified mail addressed to its last known place of business. Failure to
file proof of such a service with the county clerk within thirty-five
days after the notice of lien is filed shall terminate the notice as a
lien. Until service of the notice has been made, as above provided, an
owner, without knowledge of the lien, shall be protected in any payment
made in good faith to any contractor or other person claiming a lien.