Hmm, also seems like there is a big personal feud there: http://fortune.com/carl-icahn-bill-ackman-feud/

Seems a little game of thrones-y.

Sometimes I wonder how much of our rational "systems" are mere fronts for powerful people no different from the chieftains of pre-history. Sigh.

They doubled their money in five years. The potential for that was probably sufficient reason for them.

It's an investment they think they'll see return on, and apparently don't have moral compunctions about.