I also think this may be the early Andresen pattern. The bottom along with the handle tells the story. Andresen was also pretty careful about patenting and trademarking everything. Nothing to definitely tie it to Andresen though. I'm not at home right now but will measure both the Andresen pan and this one to see if they are the same (I picked one up earlier this year).
Paul and I spoke briefly about it but I can't remember if he has one or not.
Tom