Re. imply versus declare
I didn't expect to disuss the english language. I can't enter into a lengthy discourse re. your idiosyncratic definition of the word "imply". I don't know what your definition is, but mine is the same as can be found in Webster's, Random house, and the Oxford dictionary--"to indicate or suggest, without express statement, as something to be inferred". The statement, "4UT is identified as a German acceptance quality control" is a declarative statement--"to make known in explicit or formal terms". That one does not agree with the statement, or that that one does not understand it, is another matter. Your disagreement does not change the form of a declarative statement into an implication. This is basic 6th grade grammar which I learned when Sister Lucretia taught my class to diagram our sentences about 45 years ago. I recall that she reinforced these lessons by pulling on my ear until it seemed that my feet left the ground. Yet, I remain incapable of explaining the derivation of these terms, imply and declare. I can't tell you why they mean what they mean, and must admit that I concede such issues to the likes of Noah Webster and other lexicographers.
You asked me how I reached the conclusion that ALL 4UT pistols were purchased by the German Military. Firstly, I need to clarify that I did not say that. I said, "it is LIKELY that all 4UT pistols were USED by the Heer". Words have meaning, and for a few decades, I have been very careful in my use of language. I believe these words were used deliberately by the originator of the statement. The word "likely" (seemingly true or certain; probable) and "USED"--not the word "purchased". "Likely" is an important word in this statement. I don't know if all 4UT Berettas went to the German Army, but I do know the following.
1. Jan C. Still, in Axis Pistols, page 107, states,
"It is likely that almost all of the 4/UT, ...were used by the German Army". He also includes two other variations in this statement, "1944 dated and blank slide Model 1935".
2. Ugo Menchini, in Pietro Beretta Le Automatiche, page 326, states,
"After the 8 September 1943 armistice between Italy and the Allies, the Germans saddled Beretta with three engineers from Germany. Moreover the factory was garrisoned by the SS... Weapons of that time, even the ones produced for the Germans, bore the punch mark 4UT (Quarto Ufficio tecnico di Controllo Armi e Munizioni--4th Technnical Control Unit), impressed prior to d[e]spatch to purchasers."
3. Ugo Menchini, in Pietro Beretta Le Automatiche, regarding an M1934, page 255, states,
"In late 1940 there appears an oval including the punch mark IVU. It refers to the 4th technical Control Unit of the ***, where inspection was carried out."
4. Note that, while they seem to represent the same inspectors, the "IVU" is not the same mark as the "4UT". The IVU would be found on the pre RSI model M1934, and the 4UT would be found on the RSI model M1935.
These are the reasons why I believe that it is likely that all of the 4UT Berettas were RSI pistols. I believe that I am in agreement with both Still and Menchini.