Tuesday's Analysts' Upgrades and Downgrades

CHANGE IN RATINGS

Atheros (ATHR Quote) downgraded at Piper Jaffray to Market Perform from Outperform. Margin upside may prove challenging as 802.11g products penetrate lower-ASP equipment. $33 price target.

American Express (AXP Quote) downgraded at Friedman, Billings Ramsey to Market Perform. Valuation call, based on a $70 price target. Business remains strong.

Celanese (CE Quote) coverage initiated at Morgan Stanley with an overweight rating and $48 price target.

Dupont (DD Quote) downgraded at BB&T Capital to Hold. Stock has doubled the performance of the S&P 500 over the past year, and has reached the $55 price target. Company also posted disappointing quarterly results this morning.

Edwards Lifesciences (EW Quote) downgraded at Citigroup to Sell from Hold. Second quarter earnings of $0.57 were in-line, but downward revision to guidance, continued competitive pressure on the valve business, and minimal contribution from new products could hurt business in near-term. $44 price target.

KLA-Tencor (KLAC Quote) downgraded at Citigroup to Hold from Buy. Positive EPS revisions have driven the stock to +26% move YTD, however, this looks set to stall. Expectations running too high. Lowering price target to $65 from $70.

LifePoint Hospitals (LPNT Quote) downgraded at CIBC to Sector Perform from Sector Outperform. Second quarter EPS missed estimates significantly due primarily to bad debt, contract labor, and medical malpractice. Price target lowered to $34 from $45.