History

NOS was established in 1987 as a clearing house for the Norwegian equity derivatives market. Norwegian listed derivatives are traded at the Oslo Stock Exchange, and NOS was the clearing house for this market since its origin in 1990.
NOS cleared both listed and OTC equity derivatives, equity index derivatives, bond futures and stock borrowing and lending contracts.

In November 2001, NOS started offering clearing services to the international maritime freight derivatives market in cooperation with the International Maritime Exchange. NOS has been offering clearing services to the international bunker fuel oil derivatives market since December 2005.

In September 2006, NOS and International Maritime Exchange merged ownership, creating the IMAREX Group. At the same time, NOS sold the financial derivatives clearing business to the VPS (the Norwegian CSD).
 
In March 2007, NOS signed an agreement with Fish Pool ASA regarding seafood derivatives. NOS offers clearing services to contracts traded at Fish Pool ASA, settled against the Fish Pool, Index (FPI).
In December 2007, NOS started clearing of Nordic and Continental power derivative contracts.