First Sale Principle and the OS
Initially, M$ charged about the same price per unit for its OS licence everywhere. When GNU/Linux became an issue, M$ responded in the most price-sensitive regions by offering a very low price, even competing with illegal copies. They could do that because courts allowed copyright holders to licence works so that they could not cross borders. That practice may come to an end with a case coming before the US Supreme Court. A business is being sued for selling imported goods without a special licence.
If the court decides that a person or business should be able to sell its property unencumbered and copyright holders have no power to limit sales after the first one (not copying but selling a legal copy obtained overseas), M$ may be forced to choose either giving up its monopoly in emerging markets by not selling in those regions or giving up its cash-cow in established markets where some people willingly pay several times the cost of production for the privilege of using M$’s software. It would be sweet if the SCOTUS killed the monopoly without even trying.
Needless to say, quitting selling licences in emerging markets would be an extreme stimulus to GNU/Linux which could easily fill the void. Giving up the cash-cow in established markets would be extremely hard on the bottom line. M$ might try to hold things together for a while by lowering prices in established markets and raising them modestly in emerging markets.
This could have important consequences for emerging economies which could become trans-shipment hubs for Wintel boxes. Major OEMs would not like competing with their own products and might have to disperse their operations globally to produce more PCs in emerging markets. It’s all good. OEMs would have one more reason to ship GNU/Linux; GNU/Linux would not compete with their products so directly.
see If You've Ever Sold a Used iPod, You May Have Violated Copyright Law – The Atlantic.