David Tepper David Orrell | CNBC Billionaire investor David Tepper said the stock market is one of the most overpriced he’s ever seen, only behind 1999. Before Wednesday’s sell-off, it was “maybe the second-most overvalued stock market I’ve even seen,” Tepper said Wednesday on CNBC’s “Halftime Report.” “I would say ’99 was more overvalued.” “The market is