NEW YORK (TheStreet) -- RATINGS CHANGES

Allergan (AGN) - Get Report was downgraded at UBS to neutral from buy. Valuation call with Valeant offer pending, UBS said. Twelve-month price target is $180.

Chevron (CVX) - Get Report was downgraded at Argus to hold from buy. Valuation call, as the stock is up 16% over the past three months, Argus said.

Quest Diagnostics (DGX) - Get Report was upgraded at Bank of America/Merrill Lynch to neutral from underperform. Twelve-month price target is $58. Had positive meetings with management and the worst appears to be behind the company, Bank of America/Merrill said.

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Duke Energy (DUK) - Get Report was downgraded at Barclays to equal weight from overweight. Driven by macro and operational factors, Barclays said. Twelve-month price target is $77.

Electronic Arts (EA) - Get Report was upgraded to buy at TheStreet Ratings.

Extra Space Storage (EXR) - Get Report was downgraded at Jefferies to hold from buy. Reaching inflection point and growth set to slow, Jefferies said. Twelve-month price target is $53.

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FedEx (FDX) - Get Report was downgraded at Barclays to equal weight from overweight. Stagnant profitability and execution focused on near-term growth at expense of capital returns, Barclays said. Twelve-month price target is $140.

Flextronics (FLEX) - Get Report was upgraded at Argus to buy from hold. Company can post sustained sales growth, Argus said.

Gulfport (GPOR) - Get Report was downgraded at Wells Fargo to market perform from outperform. Company cut its production guidance by 30%, Wells Fargo said.

Gulfport (GPOR) - Get Report was downgraded at Stifel Nicolaus to hold from buy. Valuation call, based on a 12-month price target of $70.

KB Home (KBH) - Get Report was upgraded at UBS to neutral from sell. Valuation accurately reflects fundamentals, UBS said. Twelve-month price target is $15.

Mondelez (MDLZ) - Get Report was upgraded at Credit Suisse to outperform from neutral. Twelve-month price target is $42. Coffee business should create shareholder value, Credit Suisse said.

Merck (MRK) - Get Report was downgraded at BMO Capital to market perform from outperform. Twelve-month price target is $60. Company lacks near-term catalysts, BMO Capital said.

OGE Energy (OGE) - Get Report was upgraded at Jefferies to buy from hold. Valuation call with 12-month price target of $41, Jefferies said.

Oneok (OKE) - Get Report was downgraded at BMO Capital to market perform. Valuation call, as the stock is up 54% over the past year, BMO Capital said. Twelve-month price target is $66.

Penn National (PENN) - Get Report was downgraded at Morgan Stanley to underweight. Twelve-month price target is $10. Estimates also cut, given expected ongoing regional weakness, Morgan Stanley said.

Petroquest Energy (PQ) was upgraded to hold at TheStreet Ratings.

Perrigo (PRGO) - Get Report was downgraded at RBC Capital to outperform from Top Pick. Twelve-month price target is $160. Company lacks near-term catalysts, RBC Capital said.

Sanderson Farms (SAFM) - Get Report was downgraded at Goldman to neutral from buy. Valuation call, based on a 12-month price target of $80.

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Sandisk (SNDK) was upgraded at Nomura to neutral from reduce. Twelve-month price target is $85. Company has raised its target model and increased capital returns, Nomura said.

Sonic (SONC) was upgraded at Oppenheimer to outperform from perform. Twelve-month price target is $25. Company can deliver solid growth and return cash to investors, Oppenheimer said.

SPX Corp. (SPW) was downgraded at J.P. Morgan to neutral. Valuation call, as the stock has been the best performer in the group the past couple of quarters, J.P. Morgan said.

Tiffany (TIF) - Get Report was upgraded at Bank of America/Merrill Lynch to buy from neutral. Twelve-month price target is $100. Higher domestic sales should drive margin expansion, BofA/Merrill Lynch said.

Twitter (TWTR) - Get Report was upgraded at Morgan Stanley to equal-weight from underweight. Twelve-month price target is $36.

Yelp (YELP) - Get Report was upgraded at Morgan Stanley to overweight. Twelve-month price target is $69. Company has attractive growth prospects and visibility, Morgan Stanley said.

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This article was written by a staff member of TheStreet.