Sorry, can't help you. The knife could be French, German, or possibly even American. If I'm not mistaken the petit chef marque is OEM put there by the manufacturer for the importer or retailer.
The profile has been altered and the belly flattened by sharpening over the years. I could probably tell you if the knife is French or German if I had it in my hands -- French knives tend to be thinner and lighter -- but not from the picture. The handle and finger-guard/bolster are of a style common throughout the twentieth century -- at least up to the mid sixties -- so I can't even give you a good idea of the date of manufacture.
What's left of the profile looks more French than German (or American), so if you held a gun to my head and made me guess, I'd lean towards one of the Sabatiers as manufacturer, martinet forging, with the knife intended for the North American market. I kinda sorta think I might kinda sorta vaguely remember the "petit chef" marque as belonging to a large retailer. But that's all very speculative -- I certainly wouldn't lay money on it.
BDL
