The U.S. stock market opened higher on Thursday, boosted by a report showing a larger-than-expected drop in weekly jobless claim ahead of key official jobs data due on Friday. Investors await a report on factory orders due at 10 a.m. Eastern. Several Federal Reserve officials speaking today will attract investors' attention. The Dow Jones Industrial Average opened 44.06 points, or 0.3%, to 16,406.11. The S&P 500 opened up, gaining 5.36 points, or 0.3%, at 1,879.32, inching above its previous closing record. The Nasdaq Composite began the day 11.66 points, or 0.3%, higher at 4,369.83.