Analysts' Actions: AMZN YUM BSX CHK AMG

NEW YORK ( TheStreet) -- CHANGE IN RATINGS:

Activision Blizzard ( ATVI) upgraded to buy at TheStreet Ratings.

Autodesk ( ADSK) upgraded at Wedbush to outperform from neutral, Wedbush said. $45 price target. Positive checks and economic data.

Affiliated Managers Group ( AMG) downgraded at UBS to neutral from buy. $155 price target. Valuation call.

Black Box ( BBOX) upgraded to buy at TheStreet Ratings.

Chesapeake Energy ( CHK) upgraded at Stifel from hold to buy. $25 price target. Expect that some or all of the company's assets are now for sale, following the departure of the CEO.

Hub Group ( HUBG) downgraded at Stifel from buy to hold, Stifel Nicolaus said. Valuation call, based on a $39 price target.

Illinois Tool Works ( ITW) downgraded at BMO to market perform from outperform. $67 price target. Valuation call.

OpenTable ( OPEN) downgraded at Oppenheimer to perform from outperform. $54 price target. Valuation and risk of new product introduction.

Potlatch ( PCH) downgraded at DA Davidson from neutral to underperform. Valuation call, based on a $40 price target.

Yum! Brands ( YUM) downgraded at Bernstein to Market-Perform from Outperform, Bernstein said. $72 price target. Lowered outlook for China comps and unit growth.

STOCK COMMENTS / EPS CHANGES

Amazon.com ( AMZN) target raised at Jefferies. Shares of AMZN now seen reaching $330, Jefferies said. Margin and operating income better than expected. Buy rating.

Amazon.com numbers raised at Oppenheimer. Shares of AMZN now seen reaching $325, Oppenheimer said. Estimates also raised on gross margin upside. Outperform rating.

Boston Scientific ( BSX) numbers raised at Oppenheimer. Shares of BSX now seen reaching $7, Oppenheimer said. Estimates also raised on recent pipeline acquisitions. Perform rating.

Continental Resources ( CLR) target raised at Jefferies to $98, Jefferies said. Adjusting ahead of the quarter. Buy rating.

Canadian Pacific Railway ( CP) numbers raised at Jefferies. Shares of CP now seen reaching $105, Jefferies said. Estimates also raised on solid revenues and better cost management. Hold rating.

Salesforce.com ( CRM) target raised at Oppenheimer to $200, Oppenheimer said. Gaining middleware share. Outperform rating.

EMC ( EMC) numbers cut at BMO. Shares of EMC now seen reaching $28, BMO said. Estimates also lowered on quarterly results. Outperform rating.

International Paper ( IP) target raised at UBS to $46, UBS said. Some upside if IP can deliver on runway. Buy rating.

Eli Lilly ( LLY) numbers raised at Citigroup. Shares of LLY now seen reaching $60, Citigroup said. Estimates also increased as stronger base undervalues Ramucirumab call option. Buy rating.

Pentair ( PNR) target raised at Oppenheimer to $57, Oppenheimer said. Plan in full swing. Perform rating.

Valero ( VLO) numbers raised at UBS. Shares of VLO now seen reaching $48, UBS said. Estimates also increased to reflect higher capture rates in Gulf Coast. Buy rating.

Valero numbers raised at Oppeneheimer. Shares of VLO now seen reaching $55, Oppeneheimer said. Estimates also raised on share buyback and dividend growth. Outperform rating.

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