[3] NV Ingenieurskantoor voor Scheepsbouw (IvS) was founded on 21 July 1922 and initially was led from the Germaniawerft in Kiel, Germany.
In 1936 it was reported in the media that there had been negotiations between Turkey, IvS and Dutch shipyards about a potential order for another four submarines, however, due financial concerns it came to nothing.
Construction of the first two prototypes started in December 1934 at the Baltic Shipyard in Leningrad, using German diesel engines and electric batteries.
In 1945 the Soviet submarine S-13 was responsible for the sinking of the German military transport Wilhelm Gustloff and the General von Steuben with heavy losses of life.
A fifth IvS design was the small submarine Saukko, built in Helsinki by the Sandvikens Skeppsdocka och Mekaniska Verkstad shipyard, and originally planned to be deployed in Lake Ladoga.
[citation needed] The contracts were worded in such a way that IvS employees (many of whom were former Kaiserliche Marine and Reichsmarine personnel) were involved with crew training and selection, and were also allowed to take part in submarine service trials.
[15] Battlecruisers were deemed by some to be essential for the defense of the Dutch East Indies against possible Japanese expansion, especially as the Netherlands lacked any large surface ships.
In the end, political disagreements delayed the decision-making process and none of the projected ships were laid down, as on May 10, 1940 the Germans invaded the Netherlands.