Mine does say "Holton Collegiate".It may have just read "Collegiate" without the Holton. Have these been confirmed not to be made by Holton, though ? This was a long time ago, like 15 years, that I worked on that horn. I don't think I have pics any longer. But that'd be interesting...
I can't remember exactly how I learned these weren't made by Holton (and of course, Holton and Couturier may well have had some kind of common ownership). But I've seen a few pictures labeled "Lyon and Healy" with that characteristic G# touch, and mention of Couturier. Compared to the two Holton sopranos I've owned with the "Frank Holton" name on, there are some details that appear the same as Holton and some that appear different. That's not very conclusive, not to someone with my limited amount of exposure to these things.
You probably already know this, but despite a very French-sounding name it appears Couturier was a US company, very small, and almost nothing is known about them, and it appears that they pretty much only made stuff under other people's names.
It's really really hard for most of us to assign manufacturer to stencil sopranos from the 20s and 30s as they all look pretty much alike. I think it'd be really difficult for anyone who isn't a tech with a long history of dealing with sopranos and a bank of detailed mechanism photos to refer back to.
