Benzinga's Top #PreMarket Gainers

KLA-Tencor Corp KLAC shares climbed 15.58 percent to $62.25 in pre-market trading. Lam Research Corporation LRCX announced its plans to buy KLA-Tencor in a $10.6 billion deal. KLA-Tencor also reported upbeat quarterly earnings. Biogen Inc BIIB shares rose 6.84 percent to $284.00 in pre-market trading after the company reported upbeat quarterly results and announced plans to lower 11 percent of global workforce. ARM Holdings plc (ADR) ARMH shares surged 6.77 percent to $47.80 in pre-market trading on strong Q3 processor royalty revenue. SanDisk Corporation SNDK gained 4.81 percent to $78.81 in pre-market trading after the company agreed to be acquired by Western Digital Corp WDC for 19 billion. Energy Recovery, Inc. ERII shares rose 4.64 percent to $7.66 in pre-market trading after jumping 197.56 percent on Tuesday.