Wall Street eyes Yellen, GDP

Janet Yellen
Joshua Roberts | Reuters
Janet Yellen

U.S. stock index futures pointed to a flat to slightly lower open on Friday, as Wall Street attempted to halt this week's losses.

Stocks have not posted gains for a single day so far this week.

Federal Reserve Chair Janet Yellen will speak shortly before closing bell on Friday, and Fed Vice Chair Stanley Fischer spoke earlier during the day in Frankfurt, on regulatory issues.

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Futures were little changed following the report that the third estimate for fourth-quarter U.S. gross domestic product (GDP) was unchanged at 2.2 percent. While corporate profits fell, consumer spending was revised higher to 4.4 percent from 4.2 percent, the fastest rate since the first quarter of 2006.

Most analysts expected a rise in overall GDP to 2.4 percent from 2.2 percent. However, a few research reports held that weak U.S. economic data could result in a negative revision.

Later in the morning comes the University of Michigan's final consumer sentiment reading, which may be a little higher than the preliminary reading, due to easing gas prices and financial market volatility.

The major earnings report out on Friday is BlackBerry, which earned four cents per share for its latest quarter, compared to an expected four cent per share loss,but revenue was far below Street forecasts as sales from services exceeded those from hardware.

In other corporate news, Dow Chemical will spin off part of its chlorine derivatives business and merge it with Olin Corporation, creating a company with annual revenue of about $7 billion. It will get about $2 billion in cash and about $2.2 billion in Olin stock as part of the deal.

American Apparel's ex-CEO Dov Charney is seeking $40 million in damages for alleged breach of his employment contract. Charney was removed from his job in December following a six-month suspension amid allegations of misusing funds.

Apple Chief Executive Officer Tim Cook plans to donate his estimated $785 million fortune to charity, according to a Fortune article.

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Amazon.com is in talks to buy online luxury retailer Net-a-Porter, according to Forbes, in what might be the largest-ever acquisition for Amazon

CNBC"s Peter Schacknow contributed to this report.