United States Steel stock plunged after the bell, dipping close to a 52-week low after reporting a fourth-quarter loss of $999 million, citing tough market conditions and lower average prices. Mario Longhi, U.S. Steel CEO told NBC News last year the company was strategizing to overcome headwinds in energy, a strong U.S. dollar and foreign "dumping."
And United Airlines edged higher with light after-hours trading volume after two shareholders, Altimeter and PAR Investment, reported activist positions in the airlines. The hedge funds now have a combined stake of 5.5 percent in United Continental, SEC filings showed.
Shares of Molson Coors Brewing also slid after the bell. The maker of beers like Coors Light and Blue Moon announced it will underwrite a public offering of $2.35 billion of shares of its Class B Common Stock. The proceeds of the offering will be used in the merger of brewing giants Anheuser-Busch InBev SA/NV and SABMiller.
Insurance giant AIG dipped slightly as well. The company announced a series of strategic actions, including divestiture or sale of several units, an IPO of its United Guaranty business, and a return of $25 billion to shareholders over the next two years. However, it said a full breakup of the company would detract from shareholder value. Investor Carl Icahn renewed calls for the company to split up in an interview with The Wall Street Journal Tuesday afternoon.
— CNBC's Everett Rosenfeld, Peter Schacknow and the Associated Press contributed to this report.