Shares of Qualcomm plunged in early trade Thursday on news of a US antitrust investigation as broader US equity markets were flat, one day after the Dow and S&P hit new records.
Meanwhile electric luxury car maker Tesla Motors gained 6.1 percent as third-quarter sales came in nearly double the level of a year ago at $851.8 million, overcoming doubts about the sustainability of its sales.
Deutsche Bank said Tesla's near-term production targets were disappointing, but that the long-term outlook remained strong.
About 40 minutes into trade, the Dow Jones Industrial Average stood at 17,486.40, up 1.87 point (0.01 percent).
The broad-based S&P 500 dipped 2.59 (0.13 percent) at 2,020.98, while the tech-rich Nasdaq Composite Index added 0.43 (0.01 percent) at 4,621.15.
Chip-developer Qualcomm tumbled 11.8 percent as it disclosed that the US Federal Trade Commission is in the early stages of an investigation into its licensing business.
Also dealing with a year-long antitrust probe in China, according to the Wall Street Journal, Qualcomm also reported fourth-quarter earnings below expectations.
Fresh US economic data lent some support to buying. The Labor Department reported that initial jobless claims fell by 10,000 to 278,000 in the week ending November 1, the lowest level in 14 years.
The good claims report "is another marker that fits with expectations for nonfarm payroll gains to exceed 200,000" when the monthly US jobs report is released Friday, said Briefing.com analyst Patrick O'Hare.
Whole Foods Market shot up 9.8 percent after reporting a 5.8 percent increase in fiscal fourth-quarter profits to $128 million behind a 3.1 percent rise in same-store sales.
Bond prices fell. The yield on the 10-year US Treasury rose to 2.36 percent from 2.35 percent Wednesday, while the 30-year advanced to 3.08 percent from 3.07 percent. Bond prices and yields move inversely.