Stocks opened in negative territory following the worse than expected earnings and revenue reported by Alcoa (AA), which is traditionally seen as the company that "kicks off" earnings season for a given quarter. This earnings season is being highly anticipated and investors were clearly disappointed with the miss. The market picked up downside momentum throughout the morning, with each of the major equity averages down by 1% or more at their worst levels. Oil prices are also down about 1.3%, but remain above $50 per barrel.

Economic News

In the U.S., the NFIB small business optimism index dipped to 94.1 in September, its weakest reading since May.

Company News

Shares of Alcoa have dropped about 10% near noon after reporting worse than expected quarterly results, with revenue falling and the company cutting forecasts for its parts businesses. This comes just weeks ahead of Alcoa's plan to separate into two independent publicly traded companies on November 1.

Samsung (SSNLF) halted production and distribution of its Galaxy Note 7, asked carriers to stop sales and exchanges of the device, and also asked customers with both original or replacement devices to power down and stop using the phone. Shares of rival smartphone maker Apple (AAPL) advanced almost 1% after the announcement.

Major Movers

Among the notable gainers was Momenta Pharmaceuticals (MNTA), which advanced almost 12% after Barclays analyst Douglas Tsao upgraded the stock to Overweight.

Also higher was YUM! Brands (YUM), which gained about 2% after the company said the separation of its China business will be complete on October 31 and that it expects to return as much as $13.5B to shareholders by 2019 as part of a program started last year. Further, the owner of Pizza Hut, KFC and Taco Bell expects to increase franchise ownership to at least 98% by 2018.

Among the noteworthy losers was Rent-A-Center (RCII), which dropped 28% after pre-releasing worse than expected financial information for the third quarter, explaining that system performance issues and outages with its new point-of-sale system resulted in a larger than expected negative impact on Core sales. Peer Aaron's (AAN) is also down more than 11% after Rent-A-Center's announcement.

Also lower was Illumina (ILMN), which slid about 25% after the company reported preliminary third quarter results that were worse than expected. Additionally, St. Jude Medical (STJ) dropped about 3% after the medical device maker warned about premature battery depletion of some of its defibrillators, an issue which has been linked to two deaths.

Indexes 

Near midday, the Dow was down 165.49, or 0.9%, to 18,163.55, the Nasdaq was down 68.26, or 1.28%, to 5,260.41, and the S&P 500 was down 21.92, or 1.01%, to 2,141.74.