 In 1996 Heesen, already known for its earlier Striker sport fishing boats, entered the market for large sport fishing yachts with the delivery of the 37 metre (121ft) "Obsession", a yacht that could reach a speed of 33 knots.At that time she was the world’s largest sport fishing yacht.Heesen expanded in 2003, the same year it launched its 3700 and 4400 yacht series.