There is often confusion with the type designation of Fokker aircraft.

This is partly the result of how Fokker self has handled the correct type designation with the correct aircraft.

An example of this is the D.XII fighter from 1923: A prototype as a half-decker and two successive aircraft as a full biplane with modified tail and engine still kept the same D.XII designation.
Very confusing with photo verification in the Fokker history.

After staging a fighter aircraft competition by the United States aviation authorities, Reinhold Platz developed the D.XII based on a USAAS specification.
The prototype was developed from the D.IX and D.XI, with the same eight-cylinder Hispano-Suiza 8Fb 300 hp engine.
The underwing of this one-and-a-half-decker had a considerably smaller wingspan than the upper wing.

The other two D.XIIs had two thin wings of the same wingspan.

A 375 and 440 hp Curtis engine was also tested for the American market and the shape and size of the tail was changed compared to the prototype.

The first flight with the 440 hp Curtis engine took place on August 21, 1924.
The prototype had V-struts between the wings, the next two aircraft had N-struts between the wings.
The D-XII with Curtiss engine, however, did not meet the requirements of the Americans and the D.XII was not purchased by the USAAS.

Naturally, the series machines produced, if any, would be equipped with armament as a fighter aircraft.

However, it remained with three test planes.