Two more REITs have seen executives forced to sell stock. Macerich Co. CEO Art Coppola and Developers Diversified chairman and CEO Scott Wolstein both had to sell stock because of margin calls. Coppola sold $13.9 million in shares while Wolstein sold $20.1 million in shares, according to company SEC filings. Part of the problem at General Growth Properties (see story at right) was that the firm had asked its way onto the short-sell ban list and then saw its executives sell shares. It made it seem like the company was protecting its share price while executives dumped stock. That's not necessarily what was going on, but it certainly didn't look good. At any rate that wasn't the case at Macerich or Developers Diversified. Instead, the problem was that share prices fell by so much that they triggered automatic margin calls.