Lots of interviews with Amazon employees and internal documents show that, despite Amazon's official claims to the contrary, they do use the sales data of 3rd party vendors to develop rival products fr their own brand. How happy for everyone that I am literally just finishing a paper and model statute that addresses this problem.
https://www.wsj.com/articles/amazon-scooped-up-data-from-its-own-sellers-to-launch-competing-products-11587650015
https://www.wsj.com/articles/amazon-scooped-up-data-from-its-own-sellers-to-launch-competing-products-11587650015