U.S. stocks were gaining after Time Warner (TWX) rejected an $80 billion buyout offer from 21st Century Fox (FOXA), and Intel (INTC) jumped after earnings beat Wall Street forecasts. The chipmaker also announced a buyback plan and Apple (AAPL) entered into a deal with longtime rival IBM (IBM) to create business apps for corporate customers. Blackberry (BBRY) dropped on the news investors didn't take the news. In Washington, Federal Reserve Chair Janet Yellen testified for a second day before Congress. TheStreet's Susannah Lee reports from Wall Street.