Family Code § 3422

(a) Except as otherwise provided in Section 3424, a court of this state that has made a child custody determination consistent with Section 3421 or 3423 has exclusive, continuing jurisdiction over the determination until either of the following occurs:

(1) A court of this state determines that neither the child, nor 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.

(2) 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.

(b) A court of this state that 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 3421.