New York Consolidated Laws, Not-For-Profit Corporation Law - NPC § 707. Quorum of directors

Unless a greater proportion is required by this chapter or by the certificate of incorporation or by a by-law adopted by the members, a majority of the entire board shall constitute a quorum for the transaction of business or of any specified item of business, except that the certificate of incorporation or the by-laws may fix the quorum at less than a majority of the entire board, provided that in the case of a board of fifteen members or less the quorum shall be at least one-third of the entire number of members and in the case of a board of more than fifteen members the quorum shall be at least five members plus one additional member for every ten members (or fraction thereof) in excess of fifteen.