A prodigious designer, Jac M. Iversen is reported to have designed and constructed more than 1000 yachts. He began his design career in Son, on the east side of Oslo fjord in Norway. He was also one of the founders of the Soon Yacht Club (note - spelling norms have changed over the years...).
In this period, from 1907 to 1926, he constructed something on the order of 400 yachts - 280 coming from a single boatyard. Like many other top designers of yesteryear, Iversen was an active competition sailor, combining design knowledge with practical experience to refine newer designs.
He spent several years in Gothenburg after moving from Norway, but soon settled permanently in Stockholm.
A great number of his design drawings are preserved in the Norwegian Maritime Museum in Oslo and the Marine Historical Museum in Stockholm.