Price fixing is when competitors agree to set prices. If AirBnb and Hilton and Marriott started agreeing on prices, then it would be price fixing. This isn't

Price fixing is when competitors agree to set prices. If AirBnb and Hilton and Marriott started agreeing on prices, then it would be price fixing. This isn't price fixing because companies aren't considered their own competitors. It might be a little fuzzy if the people posting rooms on AirBnb are considered competitors, but even then it's not price fixing because there's no requirement to use the algorithm's suggested price, and no single owner can influence the general price of rooms, because there's still hotels, motels, non-AirBnb rooms, etc.