Birkenstock, which is enjoying a boom in the American shoe market, has notified Amazon that it will stop supplying it from next January. It has also asked its authorized dealers not to offer Birkenstock shoes on its marketplace. According to CNBC, Birkenstock has found it impossible to supervise the distribution of unauthorized models through Amazon in the country. The German company is reportedly claiming that a large number of copies are being offered through its internet platform, which is hosting a rising number of Chinese suppliers.