Lauffer or Stelton - Cylinda Line - Jacobsen  

Hi there!
Does someone know why the vintage pieces of the Cylinda Line serie designed by Arne Jacobsen can be stamped on the bottom in different ways?
I have seen some of these vintage objects stamped with "Lauffer Stelton Stainless Denmark" and an "AJ" logo. Or with a "Lauffer Stelton Stainless Denmark" sticker.
And I have also seen some of them (vintage too) with a sticker saying "Stelton Stainless from Denmark. Design Arne Jacobsen"
It depends on where it was produced? Is Lauffer the manufacturer in the US and Stelton in Denmark? There were allways produced by Stelton in Denmark and in the US distributted by Lauffer? It depends on how old is the object?
Thanks!