NEW YORK ( TheStreet) -- CHANGE IN RATINGS Assurant ( AIZ - Get Report) was upgraded at Bank of America/Merrill Lynch to neutral. $60 price target. Company is seeing a pricing overhang easing in Florida, BofA/Merrill said. Chesapeake Energy ( CHK) was downgraded at Stifel Nicolaus to hold from buy. Valuation call, given low expectations for production growth, Stifel Nicolaus said. Emcor ( EME) was upgraded at DA Davidson to buy from neutral. Company is leveraged to a recovering nonresidential construction environment, DA Davidson said. Corning ( GLW - Get Report) downgraded at Piper Jaffray to neutral from overweight. $14 price target. Company lacks exposure to new product cycle in display. JBHT) was upgraded at Bank of America/Merrill Lynch to buy from neutral. $81 price target. Company offers a strong secular growth story, BofA/Merrill said. Johnson & Johnson ( JNJ - Get Report) was upgraded at Goldman Sachs to neutral from sell. Pharma outlook is improving, Goldman said. $95 price target. Life Technologies ( LIFE) was downgraded to hold at TheStreet Ratings. Eli Lilly ( LLY - Get Report) was downgraded at Jefferies to underperform from buy. Estimates were also lowered, given worsening business environment and disappointing R&D productivity, Jefferies said. $40 price target. L Brands ( LTD) was downgraded at Credit Suisse to neutral from outperform. $64 price target. Comp weakness persists and inventories are building, Credit Suisse said. Merck ( MRK - Get Report) was downgraded at Jefferies to hold from buy. Estimates were also decreased on weak business environment and unimpressive cost-cutting initiatives, Jefferies said. $50 price target. PCYC) was upgraded at Goldman Sachs to buy from neutral. $170 price target. ibruttinib could generate $7.5 billion of peak annual sales, Goldman said. Premier Exhibitions ( PRXI) was downgraded to sell at TheStreet Ratings. Sonoco ( SON) was downgraded at Goldman Sachs to sell from neutral. Company will likely grow slower than its peers over the next few quarters, Goldman said.