Why are there so many exact copies of this product found on Amazon.com under different brand names?
Is the patent not valid? Or is there a legal way around selling this product under a different name?
The patent document you are referring to seems to be a pre-grant publication of an application for a Chinese Utility model. CN202723661 U. I do not see a corresponding U.S. patent. Even if it were a granted patent in China that would not affect anything in the U.S. Maybe the company in China is selling it to many branded distributors in the U.S.