One piece of confusion here is that you do not actually have to prove a literal explicit agreement between the parties to be successful. While tacit collusion

One piece of confusion here is that you do not actually have to prove a literal explicit agreement between the parties to be successful. While tacit collusion is not itself illegal, conspiracy is. Put another way: You can prohibit folks from agreeing not to compete, no matter what form that agreement takes. You don't have to know who you are avoiding competition with, etc However you can't order people to compete just because they aren't