Overseas Shipholding Group announce the appointment of Captain Robert Johnston as President & CEO. Morten Arntzen has resigned as President and Chief Executive Officer and as a director of the Company to be succeeded by Johnston. Captain Robert Johnston will serve as the President and Chief Executive Officer of the Company effective immediately. He was previously the Senior Vice President and Head of U.S. Flag Strategic Business Unit. “The Board thanks Morten Arntzen for his service, including during recent challenging times,” said Michael J.