I have checked Heribert Seitz and Nickel Ulstein books for the mark, and another couple from Solingen and the mark is not there. This just means it is not a main producer.
Fernando, what you say about Toledo could be valid for troopers swords. The 1728 regulation does not say anything about screws (you can find it here:
http://bibliotecavirtualdefensa.es/B...o.cmd?id=36321
Volume 3 page 318).
But In 1761, they write that the 1728 order shall be better enforced, from the redaction they just repeat the model 1728, with 4 screws. So I take the 1728 shall have 4 screws, but it was not always followed. Further I have seen 1728 model swords, which seem to be for troopers, with Solingen blades that shall predate Toledo (the production after 1760 was completed with swords from Barcelona) and four screws. First picture, by Gio Knecht, JKeiser, Coel...
Of course, they could be later remountings, this is not an exact science.
I just noticed the Keiser sword has a similar blade than the initial post.
Officers is a different business as they were not using always Toledo blades after 1761, and of course not before either.
By the style, older swords have only two screws. They are difficult to date and to distinguish if they are for an officer or for the trooper. This includes those from late XVIIth century. So I believe that after 1728, but possibly before, the tendency was towards 4 screws.
As for the position, next is a Coel blade with mark in the ricasso (and two screws plus another two for the guardapolvo).
Last is another with two screws with a similar motto.