A U.S. Federal Court's jurisdiction extends to those places within the territorial boundaries of the USA, or where the U.S. Court has authority under consent of a foreign power. Obviously, no jurisdiction extends to Switzerland.
However, where a foreign organization has property interests and assets which are within U.S. territorial control, it is sometimes possible to enforce a court order, by permiting the enforcing party to reach the foreign organization's property. This cannot happen unless the organization is actually a party to an action -- merely being a witness is insufficient to pemit a federal court to exercise control.
Generally, when trying to obtain information from a foreign organization, a court will issue "letters rogatory" to the subpoenaing party, who will then seek an order from the foreign court to permit a subpoena or other legal process to issue. Whereupon a foreign attorney will be retained to effect legal process and obtain the requisite information.
The Swiss corporation could, of course, simply volunteer the information to you. But, absent an order from a Swiss court, there is no way for you to force the discovery.
Similar procedures would be required for any foreign organization.
Hope this helps.
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