Becoming so dominant in your industry that you suck out all the oxygen needed for competitors to survive is a hallmark of what are known as virtual monopolies. They’re perfectly legal and can make a great investment because they have almost the entire field of play to themselves.
Three Motley Fool investors identified Live National Entertainment (NYSE: LYV), Facebook (NASDAQ: FB), and Monsanto (NYSE: MON) as companies with competitive moats so wide as to be virtual monopolies in their field.