Take a look at some of Monday's morning movers:
Precision Castparts—Warren Buffett's Berkshire Hathaway announced plans to acquire the maker of aircraft equipment for $235 a share, making for an all-cash deal of about $37.2 billion. Shares of Precision Castparts jumped nearly 20 percent in premarket trade.
IBM – Shares of the tech hardware firm edged higher in premarket trade after Warren Buffett said "he loves it" when IBM's stock price goes down because the company can repurchase shares at better prices. Buffett's Berkshire Hathaway has an 8.12 percent stake in IBM, according to recent filings.
Alibaba- The Chinese e-commerce giant will take a 19.99 percent stake, 28.3 billion yuan ($4.56 billion), in Chinese electronics retailer .
Twitter – Dick Costolo, who stepped down as chief executive in June, plans to leave the company's board of directors by the end of the year or when a new chief executive is appointed, according to sources familiar with Costolo's plans. Shares of the social media firm gained about 1.7 percent in premarket trade.
AstraZeneca – The pharmaceutical firm announced a deal with Invovio Pharmaceuticals for the rights to an experimental immune system-boosting medicine. The agreement is AstraZeneca's third deal in less than a week to boost its cancer drug line.
Freeport-McMoran – The natural resource company has entered an agreement with JPMorgan Chase to sell up to $1 billion in common stock. The firm said it may use proceeds for repayment of loans and financing of working capital and capital expenditures, among other purposes. The stock fell more than 2 percent in premarket trade.
Dean Foods – The largest U.S. milk processor posted its second-straight decline in quarterly sales, pressured by lower volumes as prices remained high despite lower raw milk costs. Net sales fell 15.8 percent to $2.01 billion. Net profit was 28 cents a share in the second quarter versus a loss of 1 cent a share in the same period last year.
Sysco – The food distributor reported a 0.9 percent increase in quarterly sales from the same period last year. Gross profit rose 3 percent to $2.2 billion, with a 35 basis point increase in gross margin to 17.9 percent. The firm said food cost inflation was flat, while foreign exchange headwinds decreased sales by 1.4 percent. Diluted earnings per share was 12 cents, a decrease of 72 percent from the same period last year.