So now we know what the Swedish population get up to in those long winter nights......
I don't know anything about the Corton name, but it sounds like a name that has done the rounds like "Vito". As spike said, the Czech company Amati use the Corton name now. I have no idea who used it, or how it was used, before Amati had it. It might be just like Leblanc use the Vito name, but there is a huge and often vague history (with very authorative threads about it on the SOTW web site) of the fortunes of the Vito mark over the passage of time.
But I suspect that, rather than Yani exporting, it is more a matter of another company taking the initiative and importing from Japan, stenciling the instruments as Corton De Lux.
Again, similar to the link between Leblanc and Yanagisawa, when (I think, correct me if I have it wrong) Leblanc took over the Vito mark and first sold a Vito range of saxophones made by Yanagisawa (as Vito VSP), but then made by Yamaha and now their Vito model is a student model made in Taiwan
Chris