William Ackman has had a rough go of it with some of his investments — particularly a $2 billion bet on Target Corp. that's lost 90 percent of its value. In March, the activist investor made a bid to get seats on two boards — those of Target and troubled mall REIT General Growth Properties. For Target, he proposed a plan — rejected by company management — to spin off its real estate as a separate company. He's trying to get five seats on the board there. For General Growth — where he has taken stakes that could give his Pershing Square Capital Management LP 25 percent of the company, Ackman advocates a bankruptcy plan in which “the equity survives intact.”