Top Percentage Gainers And Losers As Of 2 p.m. 4/12/2011 (CYH, THC, IDIX, BAC, SKH, JPM, BIO, REDF, DEER, THC, CYTX, CCRT, WMS, EXTR, LFT, SB, DRRX, BRNC, MCRL)

Best

1) Community Health Systems (NYSE: CYH): Shares are surging 13.09% to $2.32 as skepticism grows about Tenet Healthcare’s (NYSE: THC) lawsuit against the company. The stock took a huge hit in yesterday’s session, trading down as low as $22.32 after Tenet’s lawsuit alleging illegal admission of patients in order to benefit financially came to light. The stock is gaining despite a downgrade from Above Average to Average at Caris.

2) Idenix Pharmaceuticals (NASDAQ: IDIX): Stock has continued to climb throughout the day, currently up 6.58% to $3.40 after starting the day in the red. The company was upgraded from Neutral to Buy at Bank of America (NYSE: BAC) yesterday morning.

3) Skilled Healthcare Group (NYSE: SKH): Stock has risen 8.84% to $15.26. The company has retained J.P. Morgan (NYSE: JPM) to assist in a possible future sale of the company. Shares had been up as much as 14% earlier in the session.

4) Biodel (NASDAQ: BIO): Shares of this development stage pharmaceutical company have been on a roll since 11 a.m. EST., currently trading higher by 7.49% to $2.44.

5) Rediff.com India (NASDAQ: REDF): Enjoying a 6.8% pop to $7.85 after spending the early morning in negative territory. The stock bounced off of its 20-day moving average on a six month daily chart earlier in the session.

Other notable movers: Deer Consumer Products (NASDAQ: DEER): Up 5.94% to $7.49; Tenet Healthcare (NYSE: THC): Bouncing back after yesterday’s big loss, up 6.21% to $6.84; Cytori Therapeutics (NASDAQ: CYTX): Up 6.54% to $8.14 after being initiated with a Buy at Capstone. Target price is set at $11.

Worst

1) CompuCredit Holdings (NASDAQ: CCRT): Equity is holding onto morning losses, currently down 20.85% to $5.24. The company is offering to purchase 13.1 million shares at $8 per share.

2) WMS Industries (NYSE: WMS): Shares continue to slide, taking a 17.1% hit to $30.02 after missing Wall Street earnings estimates yesterday.

3) Extreme Networks (NASDAQ: EXTR): Equity is diving 15.93% to $2.85 after missing sales estimates for the third-quarter. Bloomberg had estimated sales of $83.9 million. The company said the number would be $76.5 million at most.

4) Longtop Financial Technologies (NYSE: LFT): Shares are plunging 12.08% to $27.30 after starting the day relatively neutral.

5) Safe Bulkers (NYSE: SB): Shares have dropped 10.04% to $8.33. The company is offering 5 million shares at a 9.3% discount to Monday’s closing price ($8.40 per share).

Other notable movers: Durect Corporation (NASDAQ: DRRX): Down 9.14% to $3.18 after yesterday’s report that one of the company’s products didn’t test well; Bronco Drilling Company (NASDAQ: BRNC): Down 9.33% to $9.52; Micrel (NASDAQ: MCRL): Down 9.10% to $13.09.