First Solar Inc. and SunPower Corp., the largest U.S. solar manufacturers, fell the most in at least four weeks after third-quarter sales slumped.
First Solar declined 8.9 percent to $22.54 at the close in New York, the most since Oct. 5. SunPower slid 7.9 percent, the most since Aug. 30.
First Solar’s sales slumped 17 percent to $839 million from a year earlier as the Tempe, Arizona-based company completed or slowed construction on some large U.S. solar farms, according to a statement yesterday. SunPower, majority owned by Total SA, said sales declined 8 percent to $649 million, mainly due to lower shipments in several European markets.
First Solar lowered its 2012 sales forecast to $3.5 billion to $3.8 billion, from its August forecast of $3.6 billion to $3.9 billion. San Jose, California-based SunPower expects fourth-quarter sales of $650 million to $850 million, and neither company provided information about next year.
“Neither one of them had much specific about 2013,” Robert Stone, an analyst at Cowen & Co. in Boston, said in an interview today. “You didn’t even get a rough outline of what next year looks like and there’s lots of reasons to be uncertain,” including continuing slow demand in Europe and questions about U.S. incentive programs.