Catch up on today's top five analyst downgrades with this list compiled by The Fly: 1. Ultragenyx (RARE) was downgraded to Neutral from Buy at H.C. Wainwright and to Neutral from Outperform at Wedbush. 2. Grainger (GWW) downgraded to Underperform on pricing risks at Credit Suisse with analyst Andrew Buscaglia telling investors he sees more uncertainty around its pricing strategy for its highest margin mid-sized customers and continued gross margin declines in 2018 that will weigh on shares. Buscaglia believes Grainger is the most susceptible to the Amazon (AMZN) threat as evidenced by its pricing actions to its more profitable smaller-medium sized customers and said its move online makes it more susceptible to competitive pricing. 3. Interactive Brokers (IBKR) downgraded to Market Perform at Keefe Bruyette with analyst Kyle Voigt citing the company's first quarter results. 4. Regions Financial (RF) downgraded to In Line from Outperform at Evercore ISI with analyst John Pancari citing limit upside to valuation given mounting earnings headwinds. 5. Sirius XM (SIRI) downgraded to Underweight from Equal Weight at Morgan Stanley with analyst Benjamin Swinburne telling investors the business is maturing and growth is slowing. Swinburne said Sirius is executing well, but the benefit from new car turnover has likely peaked and not longer adds material to the subscription base, and adds used car growth has also peaked. This list is just a portion of The Fly's full analyst coverage. To see The Fly's full Street Research coverage, click here.

W.W. Grainger's board of directors approved a quarterly cash dividend of $2.05 per share, an increase of 10% from the most recent company dividend of $1.86 per share. The dividend is payable on June 1, to shareholders of record on May 13. In addition, the board approved the repurchase of up to 5M shares of the company's outstanding common stock, replacing the company's existing repurchase authorization. The new repurchase authorization has no expiration date. "2024 is on track to be our 53rd consecutive year of increased dividends, upholding Grainger's long-standing commitment to our shareholders. This increase, together with our updated share repurchase authorization, reinforces our ability to continue investing in the business while also returning excess cash to shareholders," said D.G. Macpherson, Grainger CEO.

Citi upgraded Sirius XM (SIRI) to Neutral from Sell with a price target of $3.30, down from $4.10. Over the last few months, the net asset value discount between Liberty SiriusXM (LSXMA) and Sirius XM has narrowed from 40% to 2%. To Citi's surprise, this occurred via a decline in Sirius XM's equity without appreciation in Liberty SiriusXM's value. The firm now finds the risk/reward in both securities as relatively balanced. As such, Citi upgraded Sirius XM from Sell to Neutral and downgraded Liberty SiriusXM from Buy to Neutral.

Pivotal Research upgraded Sirius XM (SIRI) to Buy from Hold with a price target of $4.90, down from $5.05. The magnitude of the decline in Sirius XM's valuation has been surprising, exacerbated by a current lack of institutional ownership and the fact most investors owned parent Liberty Sirius XM (LSXMK) to play the narrowing of the net asset value gap rather than as a way to invest in Sirius, the analyst tells investors in a research note. The firm says this has created an attractive investment opportunity, highlighted by the 55% upside to its new target price. It views Sirius as a free cash flow acceleration story.