First, the old Suhl gunmaker was named "Simson", not "Simpson". Mr Simpson is an American arms dealer who imports many old guns, among them drillings, from Europe.
Are you talking about a pre- or post-WW2 Simson drilling? If prewar, it is likely pre-1933, when the jewish Simson family was dispossessed by the Nazis. If made post-WW2, from the 1950s on, the name "Simson" on the gun does not matter at all. The GDR commies used the Names "Merkel", "Simson", "Fortuna", "Hubertus" of the expropriated former Suhl gunmakers just as trademarks for the products of their ETW = Ernst Thaelmann Werke "people owned combine". Guns with these trademark names were essentially all made by the same people. Merely the names on them varied, according to export market preferences.
As you are concerned and nitpicking about your "copyright" and "intellectual property" you will find little help on the internet. The net simply is no place for such people.