Similar to the logic behind the stagnation of microsoft stock over the last decade - institutional investors just owned as much of it as they were allowed to.
great point w.r.t. MSFT. I actually think that with FB, institutional investors are responsible for the move back higher. As long as the social space exists and this is the big name there, it will be important for them to have some holdings. The outstanding float is pennies compared to overall investment dollars.