Cruelty free brand x ingredients

Hello guys, maybe an expert or even a brand can help me to understand this, I explain: One of my favorite cientists said in his poadcast that when we see brands claiming that they don't test in animals it only means that they don't manufacture their owns ingredients. Because when you are selling it you need to be certified let's say. So another company has it tested and then they buy the ingredient and add it I their formula production. I don't know if I am clear enough in my explanation, but I would like to know if that's the case with skincare too. Do you know anythings about it?