Torben may be correct in his identification of the full factory name for the company that made these cartridges. I simply do not know. The only way I have seen the name of the factory is from a box label, where it is shown simply as "Nederlandische Patroenenfabreik, Dordrecht. The factory at Dordrecht had some commercial ties to Hirterberger Patronenfabrik in Austria, but I am not sure to what extent.
The “D” headstamp is confusing, as it appears on cartridges from so many different factories, but there is no question that the 9mm Kurz (.380 Auto) rounds with the “D” at the 12 O’Clock position on the headstamp and four-digit dates at the bottom are from the Netherlands. I have seen these dated from 1931 thru 1933 and there could be other dates. I also have a box for these in my collection, although the label is partially missing. Beautiful pictures of boxes for these cartridges can be found on the Dutch website: www. ammopix. com (no gaps, of course, put here solely to try to fool the robot spammers)
The Dutch designation for the 9mm Kurz cartridge, more properly called the .380 A.C.P. or .380 C.A.P.H. when described in the English language, since it is the only one of the three “pocket” calibers that was first used in America, was “Scherpe Patroon No. 21”. It was used by the Netherlands in the F.N. Model 1922 Pistol, designated in Holland as “Pistool M.25 No. 2”.