Afternoon Market Losers

Kandi Technologies KNDI dropped 14.84 percent to $6.60 but shares jumped 185.98 percent over the last 52 weeks.

Celsion CLSN plunged 13.21 percent to $1.38 with a 12 month ROE of -79.88 percent.

SemiLEDs LEDS traded down 9.18 percent to $1.78 after a morning of heavy trading.

GenMark Diagnostics GNMK tumbled 8.20 percent to $12.09 on news that Natural Molecular launched a competing product.

ZIOPHARM Oncology ZIOP dropped 8.37 percent to $2.08. Shares of the company dropped 49 percent over the past 52 weeks, while the S&P 500 Index gained over 23 percent.

Biogen Idec BIIB shares declined 6.82 percent to $207.84 after Citigroup downgraded the company to Neutral rating.

Ambit Biosciences AMBI traded down 7.42 percent to $7.49.