N.Y. Domestic Relations Law § 76-A – Exclusive, continuing jurisdiction

1. Except as otherwise provided in section seventy-six-c of this title, a court of this state which has made a child custody determination consistent with section seventy-six or seventy-six-b of this title has exclusive, continuing jurisdiction over the determination until:
1. (a) a court of this state determines that neither the child, the child and one parent, nor the child and a person acting as a parent have a significant connection with this state and that substantial evidence is no longer available in this state concerning the child's care, protection, training, and personal relationships; or
2. (b) a court of this state or a court of another state determines that the child, the child's parents, and any person acting as a parent do not presently reside in this state.
2. A court of this state which has made a child custody determination and does not have exclusive, continuing jurisdiction under this section may modify that determination only if it has jurisdiction to make an initial determination under section seventy-six of this title.