SAN FRANCISCO (MarketWatch) -- KB Home CEO, President and Chairman Bruce Karatz has resigned after an internal investigation found that he backdated his own stock-option grants to increase his pay and will forfeit about $13 million in gains from the backdating, according to a media report Sunday. KB Home said Karatz would be succeeded as CEO by Jeffrey T. Mezger, the company's chief operating officer, The Wall Street Journal reported in its online edition. See Wall Street Journal story (Subscription required). KB Home also said it has created the new post of non-executive chairman and will conduct a search for...