Gregory Callimanopoulos is also behind U.K. based Sealion Shipping/Toisa Ltd, owner of around 30 offshore service vessels.

Owned by Pericles G Callimanopoulos (Hellenic Lines, Piraeus, Greece). Hellenic Lines used to be one of the largest liner companies of the '50s, 60's and 70's. With the evolution of containerized cargo, the vessels became obsolete and most of the fleet was converted to container vessels (by removing tween decks, derricks etc). The company seized operations in 1984, amongst disputes between children of late Pericles Callimanopoulos. Son Gregory Callimanopoulos set up Trade and Transport Inc, operationg bulkers and tankers, and today owns about 15 modern panamaxes, afras and suezmaxes as well as several newbuilds kamsarmaxes, with offices in Piraeus, London and New York.