There is an ongoing thread discussing this subject but I thought it best to post it here to help people locate information since Google sweeps this fourm frequently. There is very little beyond speculation elsewhere on the internet. So as usual, you can find the real information here on PipesMagazine.com.
I emailed Kai and he was kind enough to write back. This is what I was told:
In 1993 a stamp made. It was spelled incorrectly. It was some time before a new stamp made. For a period of time Kai Nielsen pipes were stamped like this:
I emailed Kai and he was kind enough to write back. This is what I was told:
In 1993 a stamp made. It was spelled incorrectly. It was some time before a new stamp made. For a period of time Kai Nielsen pipes were stamped like this: