Transfers of firearms to persons in the insular possessions of the United States are exempt from transfer tax, provided title in cases involving change of title (and custody or control, in cases not involving change of title), does not pass to the transferee or his agent in the United States. However, such exempt transactions must be covered by approved permits and supporting documents corresponding to those required in the case of firearms exported to foreign countries (see §§479.114 and 479.115), except that the Director may vary the requirements herein set forth in accordance with the requirements of the governing authority of the insular possession. Shipments to the insular possessions will not be authorized without compliance with the requirements of the governing authorities thereof. In the case of a nontaxable transfer to a person in such insular possession, the exemption extends only to such transfer and not to prior transfers.