I think the president Vitoed them. The only ones I recall are the rationales and a few Paris horns that got over here. Some of the Noblets were decent but not really a Leblanc.
If you're talking about the Leblanc Systeme horns with the thousands of alternate fingerings and set screws by the dozens, yes, Leblanc made them. I own one, sn 4xx. They only made like 1500 or so of these horns. I expect them to become more and more rare and valuable over time. I've noticed that leblanc systeme horns show up less and less often than they did a few years ago, which makes me sad, as I'd love to get a Leblanc Tenor to go with the alto.While doing the weekly eBay run this afternoon, I remembered that it has been eons since I have seen anything about Leblanc saxophones. Of the 43 pages of postings that I went through, not one "straight" Leblanc horn was mentioned, only a few Vito/Lelancs.
What gives here? I know that Leblanc produced the incredibly complicated "transposing saxs" at one point, because I've actually held and played on. BUt, where did they all go, vanishing without any apparent trace?
Inquiring minds want to know...