Catch up on today's top five analyst upgrades with this list compiled by The Fly: 1. Valeant (VRX) upgraded to Neutral from Underperform at Mizuho with analyst Irina Koffler saying while she remains concerned about Valeant's return to revenue growth, sees no near-term "sell catalysts." 2. Patterson Companies (PDCO) upgraded to Buy from Hold at Craig-Hallum with analyst Kevin Ellich saying that his sum-of-parts analysis suggests the company could unlock value by splitting its dental and animal health businesses. 3. Prologis (PLD) and AvalonBay (AVB) were upgraded to Buy from Neutral at Citi. 4. Universal Display (OLED) upgraded to Outperform from Perform at Oppenheimer with analyst Andrew Uerkwitz saying with the shares down 41% year-to-date, the stock is oversold and the risks are fully priced in. 5. Halyard Health (HYH) upgraded to Overweight from Sector Weight at KeyBanc with analyst Matthew Mishan saying he sees the company's earnings growth accelerating and valuation re-rating following the sale of its Surgical & Infection Prevention unit. This list is just a portion of The Fly's full analyst coverage. To see The Fly's full Street Research coverage, click here.