The Backward Bending Supply Curve, Asymmetric Information, and Monopoly This recent question about when monopoly is undesirable made me curious about when monopoly is actually desirable? I was reminded of an argument for the efficiency of monopolies when moral hazard effects create a backward-bending supply curve in competition, like in healthcare perhaps. But, for the life of me, I cannot remember exactly how this was justified or if I am just imagining the whole thing. Is anyone familiar with arguments like this? 

I know you can create a backward bending marginal cost curve and then with the usual linear marginal revenue curve, you might have MR=MC at a greater quantity than where demand intersects marginal cost, but I don't understand how the backward bending supply is also a a marginal cost curve--then the curve isn't even a proper function.

Information is a funny thing, so I wouldn't be surprised if incomplete information made for strange results. 

Edit: I am thinking of pictures like these. I am just having a hard time reconstructing the jump from a backwards bending supply or demand curve (I understand these--this is often taught in 101), I just don't understand the MB/MC interpretation below where it seems like you might get a higher equilibrium quantity with monopsony or monopoly.




For these to make sense, MC and MB can't be functions of quantity unless I have a marginal cost in each direction? As in I could sell $q_1$ at a high price a low price, so am I approaching from above or below.
This definitely is not a complete answer. But I can imagine the case of increasing returns to scale. Or natural entry barrier. Increasing returns to scale is often discussed in international trade theory, but it can be also relevant here.

Example: think about commercial aircraft industry, dominated by Boeing and Airbus. Aircraft industry is seen as exhibiting increasing returns to scale, so monopolistic power those companies have (well, it is oligopoly, but that does not change the conclusion) may actually lead to cheaper quality aircraft.

Now there are people who really believe that all monopolistic powers are undesirable, but I believe those people are only minorities.