Catch up on today's top five analyst downgrades with this list compiled by The Fly: 1. Pentair (PNR) downgraded to Hold from Buy at Stifel with analyst Nathan Jones saying Pentair's 2020 prospects look improved over 2019 where discrete headwinds, particularly in the Aquatics business, create easy comparisons in the first half of 2020. 2. Alcoa (AA) downgraded to Market Perform from Outperform at BMO Capital with analyst David Gagliano saying BMO's reduced aluminum price forecasts for the entirety of the aluminum supply chain leave "little incremental upside potential" moving forward in the underlying price forecasts. 3. SciPlay (SCPL) was double downgraded to Sell from Buy at Goldman Sachs while Groupon (GRPN) was downgraded to Sell from Neutral. 4. Lennar (LEN) and Fortune Brands (FBHS) were downgraded to Sector Perform from Outperform at RBC Capital while D.R. Horton (DHI) was downgraded to Underperform from Sector Perform. 5. Alexion (ALXN) downgraded to Equal Weight from Overweight at Morgan Stanley with analyst Matthew Harrison saying while he thinks the company can effectively transition Soliris to Ultomiris and maintain its large and emerging neurology franchise, he does not see the "major overhang of concentration risk" as one the company will be able to address in the near-term. This list is just a portion of The Fly's full analyst coverage. To see The Fly's full Street Research coverage, click here.