RATINGS CHANGES

Advanced Energy (AEIS) was downgraded to neutral from buy at Bank of America/Merrill Lynch. The valuation is less attractive, based on a $35 price target, analysts said. 

TD Ameritrade (AMTD) was downgraded to equal weight at Barclays. $33 price target. The company may face growth challenges in the second half of the year, Barclays said. 

Astronics (ATRO) was downgraded to sector weight from overweight at Keybanc. The valuation is less attractive with shares up 56% since February, Keybanc said. 

Boeing (BA) was downgraded to underperform from neutral at Bank of America/Merrill Lynch. $125 price target. 787 will likely not generate as much cash as expected, analysts said. 

Cowen (COWN) was upgraded to buy at TheStreet Ratings. You can view the full analysis from the report here: COWN.

DeVry Education (DV) was downgraded to underperform from neutral at Bank of America/Merrill Lynch. $18 price target. The FTC suit continues to weigh on the stock, analysts said. 

Brinker (EAT) was downgraded to equal weight at Barclays. $47 price target. Fundamentals remains challenged and disappointing, Barclays said. 

Hershey (HSY) was downgraded to underperform from buy at Bank of America/Merrill Lynch. $92 price target. The valuation is less attractive, as the company lacks near-term catalysts, analysts said. 

Kansas City Southern (KSU) was upgraded to buy from underperform at Bank of America/Merrill Lynch. $106 price target. The company has cut costs and is the only operator that is growing volume, analysts said. 

Liberty Media (LSXMA) (LSXMB) was downgraded to hold at TheStreet Ratings. You can view the full analysis from the reports here: LSXMA and LSXMB. Conversely, Liberty Media (LSXMK) was downgraded to sell at TheStreet Ratings. You can view the full analysis from the report here: LSXMK.

Medivation (MDVN) was upgraded to buy at TheStreet Ratings. You can view the full analysis from the report here: MDVN.

Northern Trust (NTRS) was downgraded to sell at Citigroup. $66 price target. The valuation is less attractive, with shares up 20% since earnings, Citi said. 

Regeneron (REGN) was downgraded to market perform from outperform at Wells Fargo. The company is facing Medicare Part B reimbursement concerns, Wells said. 

Spirit Airlines (SAVE) was downgraded to neutral from overweight at JPMorgan. $52 price target. The valuation is less attractive, with shares up 33% year-to-date, JPMorgan said. 

Spirit AeroSystems (SPR) was downgraded to neutral from buy at Bank of America/Merrill Lynch. The valuation is less attractive, based on a $50 price target, analysts said. 

St. Jude Medical (STJ) was downgraded to neutral at BTIG. The valuation is less attractive as the company lacks near-term catalysts, BTIG said. 

Tetra Tech (TTEK) was downgraded to neutral from outperform at Wedbush. The valuation is less attractive, based on a $31 price target, Wedbush said.

This article was written by a staff member of TheStreet.