Greenberg: Is Icahn Signaling a Top in Activist Investing?

SAN DIEGO (RealMoney) -- Iadon't agree with Carl Icahn on everything. He and I have agreed to disagree on a few things, though we probably agree on more than we disagree. But here's something we definitely won't agree on: I believe his tweet yesterday, about an open letter he was about to release to Apple CEO Tim Cook, may have signaled a top for activism. Must Read: 10 Stocks Carl Icahn Loves in 2014 When the letter was finally released, the reaction was almost (perhaps, ironically) as if Icahn...