RATINGS CHANGES

Cerner (CERN) - Get Report was downgraded to perform from outperform at Oppenheimer. Confidence is waning about potential sales and earnings upside, Oppenheimer said. 

Cigna (CI) - Get Report was upgraded to outperform from sector perform at RBC Capital. $172 price target. The company is still attractive on its own and has multiple positive operating levers, RBC said. 

Ford (F) - Get Report was upgraded to hold at Jefferies. $12 price target. Potential bad news has already been factored into the stock, Jefferies said. 

Intel (INTC) - Get Report was downgraded to hold from buy at Canaccord Genuity. $38 price target. The company is at a strategic crossroad and expects gross margins to decline, Canaccord said. 

Rayonier (RYN) - Get Report was downgraded to neutral at DA Davidson. The valuation is less attractive, based on a $30 price target. 

Signet Jewelers (SIG) - Get Report was downgraded to hold at TheStreet Ratings. You can view the full analysis from the report here: SIG.

Tesaro (TSRO) - Get Report was downgraded to market perform at Leerink Partners. $186 price target. The valuation is less attractive, as the stock is up on takeover speculation, Leerink said. 

Twitter (TWTR) - Get Report was downgraded to sell from hold at Loop Capital. $10 price target. The company slashed its guidance, citing increased competition, Loop said. 

Twitter was downgraded to hold from buy at Deutsche Bank. $22 price target. Recent checks suggest that large advertisers are moving elsewhere, Deutsche said. 

Twitter was downgraded to sell from hold at Citigroup. $13 price target. The company cut guidance because of increased competition, Citi said. 

Ubiquiti (UBNT) was downgraded to underperform from neutral at Credit Suisse. $44 price target. The company appears expensive, but is facing margin pressure, Credit Suisse said. 

Viacom (VIAB) - Get Report was downgraded to equal-weight at Barclays. $45 price target. The transition process will likely take longer than expected, Barclays said. 

This article was written by a staff member of TheStreet.