In Aldinger v. Segler, 263 F.Supp.2d 284 (D. Puerto Rico) the father, a German citizen, filed a petition, seeking the return of his children to Germany. The District Court held that the parties marriage contract provision did not amount to forfeiture of father's custody rights.

The parties= marriage contract provision, stating that the children would live with the mother in the event of the parties' separation, that the mother and father had joint legal custody, and that in event of divorce the court would determine custody, did not amount to a forfeiture of the father's custody rights, in event of the parties' separation, for purpose of determining whether father had custody at the time the mother removed the children from their habitual place of residence. The father was exercising his rights of custody at the time the children were removed from their habitual place of residence in Germany.

He lived at same address as children and actively participated in their lives prior to the removal.