The whole point is that microsoft is not really an 'investor' in terms of a general market. Microsoft would have competitive reasons for buying a stake in Face

The whole point is that microsoft is not really an 'investor' in terms of a general market. Microsoft would have competitive reasons for buying a stake in Facebook that go beyond a direct return on investment, which is all a normal investor is looking for. If Microsoft has a 98% of a map to buried treasure, but a critical 2% is missing, that 2% is worth a lot to Microsoft, but nothing to anyone else. Unless MS is willing to buy it from you, that is. If 1.6% is all they really need of Facebook, the rest could be worthless.