NEW YORK (TheStreet) -- RATINGS CHANGES

Aetna (AET) Was upgraded at Sterne Agee to buy from neutral. Valuation call, based on a 12-month price target of $124, Sterne Agee said.

Chesapeake Energy (CHK) - Get Report was downgraded at Sterne Agee to underweight. Twelve-month price target is $9. Estimates were also cut, given lower expected commodity prices, Sterne Agee said.

eBay (EBAY) - Get Report was downgraded at Piper Jaffray to underweight from neutral. Twelve-month price target is $49. Paypal is facing increased competition, Piper Jaffray said.

PAR Technology (PAR) - Get Report was downgraded to sell at TheStreet Ratings. You can view the full analysis from the report here: PAR Ratings Report.

Penn National Gaming (PENN) - Get Report was upgraded to hold at TheStreet Ratings. You can view the full analysis from the report here: PENN Ratings Report.

Southwestern Energy (SWN) - Get Report was downgraded at Sterne Agee to neutral. Company is diluting equity and raising debt, Sterne Agee said.

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This article was written by a staff member of TheStreet.