I know you searched the company. Looks like it has been in business for around 275 years. Don't think it is that old but I do think you got a deal. Gotta love those Flea Markets.
thats a very high quality german made--- highdollar blade you got there -- their known for the chefs knfes --I was a professional cook for almost 30 years I know good steel.
Truly a nice find and buy! Have done numerous searches for info on your knife....nothing...nada....which is a good thing! They are an OLD company. I would email them a pic of the knife and see if they send you any info...good luck and nice find!