TSC Ratings' Updates: Thoratec

Other ratings changes include Global-Tech(GAI Quote), upgraded from sell to hold, and Cover-All Technologies(COVR Quote), downgraded from hold to sell.

All ratings changes generated on Dec. 24 are listed below.

Ticker Company Current Change Previous AME Ametek HOLD Downgrade BUY ANCI American CareSource BUY Upgrade HOLD CIG CIA Energetica HOLD Downgrade BUY COVR Cover-All Technologies SELL Downgrade HOLD GAI Global-Tech HOLD Upgrade SELL HOMB Home Bancshares BUY Upgrade HOLD NSUR Iinsure.com SELL Downgrade HOLD OGE OGE Energy HOLD Downgrade BUY TCBK Trico Bancshares BUY Upgrade HOLD THOR Thoratec BUY Upgrade HOLD

Each business day, TheStreet.com Ratings updates its ratings on the stocks it covers. The proprietary ratings model projects a stock's total return potential over a 12-month period, including both price appreciation and dividends. Buy, hold or sell ratings designate how the Ratings group expects these stocks to perform against a general benchmark of the equities market and interest rates.

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