NEW YORK ( TheStreet) -- CHANGE IN RATINGS Alliant Techsystems ( ATK) was upgraded at FBR Capital Markets from market perform to outperform. $65 price target. Valuation call, as the firm is buying back more stock, FBR Capital Markets said. Annaly Capital ( NLY) was downgraded to hold at TheStreet Ratings. CF Industries ( CF) was downgraded at Dahlman Rose from buy to hold. Stock is already pricing in higher corn prices, Dahlman Rose said. Costco ( COST) was upgraded at BMO Capital from underperform to market perform. Estimates were also boosted, as the company is seeing higher sales and lower costs, BMO said. $106 price target. Gamestop ( GME) was upgraded to buy at TheStreet Ratings. Hasbro ( HAS) was downgraded at Goldman Sachs from neutral to sell. $32 price target. Estimates were also cut, given slower expected consumer spending, Goldman said. Harris Corp. ( HRS) was downgraded at Lazard to sell from neutral. $41 price target. Risk/return points down, Lazard said. Intuitive Surgical ( ISRG) was upgraded at JP Morgan from neutral to overweight. $625 price target. Estimates were also boosted, given the company's attractive sales opportunities, JP Morgan said. Lowe's ( LOW) was upgraded at Bank of America/Merrill Lynch from neutral to buy. Company should benefit from accelerating growth trends, BofA/Merrill said. $36 price target. National Bank Holdings ( NBHC) was initiated with a buy rating at Goldman Sachs. $24 price target. Among the best positioned to benefit from consolidation, Goldman said. Realty Income ( O) was upgraded at UBS to neutral from sell. $42 price target. QE3 and acquisition machine changes our near term view, UBS said. Progressive Corp. ( PGR) was downgraded at Citigroup to sell from neutral. $19 price target. Special dividend removes catalyst, Citigroup said. Riverbed Technology ( RVBD) was downgraded at Needham from strong buy to buy. Valuation call, based on a $27 price target, Needham said. Sprint Nextel ( S) was upgraded at Jefferies to hold from buy. $7 price target. Deal talks with Softbank, Jefferies said. Sandisk ( SNDK) was upgraded at Wedbush from neutral to outperform. $49 price target. NAND supply/demand outlook is improving and the company is seeing strong OEM wins, Wedbush said. Titan International ( TWI) was upgraded at Jefferies to buy from hold. Favorable risk/reward, Jefferies said. Buy rating.