Martin Marietta Materials stock fell 8 percent on Wednesday after a well-known hedge-fund manager said at a New York conference that the Raleigh company had problems.

“Recent earnings benefited from one-time fiscal stimulus that is about to wind down,” said David Einhorn, co-founder of Greenlight Capital, according to Bloomberg News.

The stock’s sudden drop triggered a circuit breaker that halted trading of the company’s shares.

Einhorn, who was in negotiations last year to buy a share of the New York Mets, is known for his activist nature and for publicly criticizing stocks that he has shorted – meaning he has bet that the stock will fall. A year ago he called for Microsoft’s board to replace CEO Steve Ballmer.

Martin Marietta issued a statement Wednesday saying its recent financial performance made it different from other companies targeted by short sellers.

“Unlike companies often targeted by shorts, Martin Marietta has come through a challenging period for the industry by carefully managing capital and making disciplined operational decisions,” the statement said.

“We are profitable and have a solid balance sheet, which will allow us to capitalize on positive industry trends and positions us well for the future.”