In 1894 he established Sandefjord Flytedokker A/S (Sandefjord Dry Docks), two wooden floating docks. A few years later, on 23 February 1887, he would go on to found what would become the world's largest whaling company of the early twentieth century, A/S Oceana of Sandefjord, with businessman and partial shareholder Carl Lindenberg, for the company Woltereck & Robertson in Hamburg. The company bought and processed seal and whale oil from Christensen vessels. A/S Oceana's original share capital was $94,000 NOK and the company was formed for the operation of the 5 whaling vessels the Polar Star, Cito, Fanklin, Penda and Aries which Christensen had bought for $73,000 NOK the year before from a bankrupt company in Larvik. The first year of operation was favorable with a surplus of U.S. $66,716 NOK.