Editor's Note: Green and red arrows refer to intraday stock price movement.NEW YORK ( TheStreet) -- CHANGE IN RATINGS Apple ( AAPL) was initiated with an Outperform rating and $410 price target at Robert Baird. Company should continue to gain market share. Arch Capital ( ACGL) was downgraded from Buy to Neutral at UBS. Valuation call, based on a $96 price target. Altera ( ALTR) was downgraded from Buy to Neutral at Ticonderoga Securities. Stock is already pricing in recent market share gains. Alexion ( ALXN) was started with a Buy rating at Goldman Sachs. $81 price target. Company was also added to the Conviction List, based on the growth potential of Soliris. Amgen ( AMGN) was started with a Sell rating at Goldman Sachs. $50 price target. Denosumab will carry high prices but offer relatively little benefit. Amgen was downgraded from Outperform to Market Perform at Leerink Swann. Investors should exercise more caution ahead of the company's upcoming binary events. Ameristar Casinos ( ASCA) was upgraded to Neutral at Merriman, Curhan Ford. Company should benefit from improving capital markets. Biogen Idec ( BIIB) was initiated with a Sell rating at Goldman Sachs. $50 price target. Company faces increased competition in the MS market. Career Education ( CECO) was downgraded from Outperform to Sector Perform at RBC Capital. $18 price target. Company is seeing lower new student growth. Chesapeake Energy ( CHK) was downgraded from Outperform to Sector Perform at RBC Capital. $30 price target. Company continues to spend. Covance ( CVD) was downgraded from Buy to Hold at Jefferies. Company is running out of room to cut costs. $45 price target. CommVault Systems ( CVLT) was downgraded to Market Perform from Market Outperform at JPM Securities. Maintain $25 price target. Discovery Communications ( DISCA) was downgraded from Outperform to Market Perform at Barrington Research. Valuation call. EOG Resources ( EOG) was upgraded from Sell to Neutral at MKM Partners. $88 price target. Stock appears attractively valued, following the recent pullback. Fresh Del Monte ( FDP) was downgraded from Buy to Hold at Jefferies. $23 price target. Banana market has deteriorated. Fortinet ( FTNT) was downgraded from Overweight to Equal-Weight at Morgan Stanley. Valuation call. Jones Lang Lasalle ( JLL) was upgraded from Neutral to Buy at Goldman Sachs. Stock is attractively valued, following a post-earnings pullback. $88 price target. Nordson ( NDSN) was downgraded to Market Perform from Outperform at BMO Capital Markets. Tougher comps coming, BMO Capital Markets said. Maintain $85 price target. Marathon Oil ( MRO) estimates changed at Barclays. 2010 EPS estimate increased to $3.40, 2011 trimmed to $3.90. Disappointing Droshky performance, Barclays said. Maintain Equal Weight rating and $36 price target.