Smurf said:Actually Marxist economics has been developed for some time after Marx's original writings. It's been developed quite a bit by many other people over the years.
And if they predicted that markets would move in the direction of more concentration, they were wrong as well. Even the traditional oligopolies, like car manufacturing, airlines, and package delivery, have seen greatly increased competition in recent decades, to the good of each market. Heck, even space travel may soon see a competitive market! The only notable industry I can think of that has become more concentrated recently is mass media. The large parent companies around today aren't so dissimilar from holding companies of the 20s which I believe were eventually found to be illegal. We'll see what happens with these.