Here are Wednesday's biggest calls on Wall Street: BMO downgrades Microsoft to market perform from outperform BMO downgraded the stock after Microsoft's earnings report, noting it has concerns about Azure growth. "We are downgrading MSFT to Market Perform based on ongoing uncertainty on Azure. We had previously placed Microsoft on our negative watch list in our 2023 outlook note published in December 2022, based largely on concerns for Azure growth." Read more about this call here. Oppenheimer downgrades Block to market perform from outperform Oppenheimer said that "volumes could swing more wildly in a downturn" for the company formerly known as Square. "Our outperform rating was predicated on SQ being able to protect adjusted EBITDA. We have learned investors really aren't focused on adjusted EBITDA vs. gross profit given the high growth multiple." Wells Fargo initiates Diamondback Energy as overweight Wells said it sees "attractive cash returns goals" for the hydrocarbon-exploration company. "We initiate on FANG at OW w/ $181 PT. Core Permian, solid execution and leading FCF payout support positive outlook." Barclays downgrades Sunrun to equal weight from overweight Barclays says it's concerned about slowing residential demand for solar. "With U.S. residential solar demand expected to slow in 2023, we are adjusting our ratings to reflect our expectations for SPWR and RUN and how they will fare in the changing environment." Read more about this call here. Bank of America initiates Papa John's as buy Bank of America said the pizza chain stock is attractive and that it sees a return to growth. " PZZA's relative valuation of 1.4x sits modestly below its 5-year and 10-year averages of 1.5x, reflecting concerns about the secular outlook for the pizza category." Bank of America downgrades Booking Holdings to neutral from buy Bank of America said it sees "less valuation upside" for the online travel booking company. "Peers comps get tougher in 2Q, and we downgrade Booking to Neutral from Buy as we see less valuation upside looking out to our now above-Street 2024 ests." Gordon Haskett downgrades Airbnb to underperform from hold Gordon Haskett downgraded Airbnb due to "overly aggressive Street top-line estimates." "Downgrading to Underperform; Expect to See Downward Top- and Bottom-line Revision w/ Consensus Estimates Overly Optimistic." Morgan Stanley names Tesla a new top pick Morgan Stanley named Tesla its new top pick and said it's attracted to its "profitability, FCF generation [and] strong balance sheet." " Tesla's recent price cuts are just the latest sign the EV market may be entering the 'shake-out' phase. We reduce exposure across the EV portfolio, while making Tesla our Top Pick." Read more about this call here. Bank of America downgrades Union Pacific to neutral from buy Bank of America said it's concerned about "service and cost pressures" for Union Pacific. "We move to Neutral given sustained pressure on costs, negative mix pressures, inflation impacts (it targets 4%), and lower fuel/accessorial gains offset by its target for rebounding service levels, lower fuel expense, and share gains above economic activity." BMO downgrades Bloomin' Brands to market perform from outperform BMO downgraded the owner of brands like Outback Steakhouse and said it sees a more "balanced" risk/reward. "We are using recent strength in BLMN shares, which coincided with accelerating BLMN/industry traffic data, as an opportunity to move to the sidelines as risk/reward has become more balanced." Goldman Sachs upgrades Philip Morris to buy from neutral Goldman said it sees a "compelling" risk/reward for shares of the tobacco giant. "We see a stepped-up growth algo & compelling risk/reward as PM enters the important U.S. market." Bank of America reiterates Amazon as buy Bank of America said it's standing by its buy rating heading into Amazon earnings, but it's concerned about Amazon Web Services following Microsoft's disappointing quarterly results. "Although the Azure FYQ2 beat gives us slightly more confidence in AWS in C4Q (and we think 22% growth is possible for 4Q), we expect Street to be more cautions on C1Q following the Azure guide." UBS downgrades Cheesecake Factory to neutral from buy UBS downgraded the stock due to concerns about a challenging 2023 macro outlook. "We are downgrading CAKE to Sell from Neutral given: i) the ~16% rise in shares YTD ii) our expectation for a more challenged macro this year which could impact results & earnings visibility; and iii) our view that risk exists to '23 margin guidance." Mizuho reiterates Robinhood as buy Mizuho called 2023 a "transformational year" for Robinhood. "Beyond 4Q, we continue to view 2023 as a transformational year for HOOD as it should benefit from new products, such as its new IRA offering." D.A. Davidson initiates Toast as buy D.A. Davidson said shares of the next-generation restaurant platform company are compelling. "The product is so compelling , Toast has already reached 11% market share with no signs of slowing down. Although macro is a concern, we note Toast has already proven its ability to power through tough times." Loop initiates Mobileye as buy Loop said the autonomous driving tech company is "best of breed." "Autonomous is already real … and it's continuing to get 'Realer.' We like investing best of breed into strong, structural long-term societal trends and autonomous and MBLY are of this ilk. Loop upgrades Fox to buy from hold Loop upgraded the media company after the Murdoch family said it was withdrawing its effort to merge News Corp. and Fox. " Fox is an under-levered media company trading at 4X EBITDA, even on our lowered estimates, and is strategically well positioned with a news and sports focus and not participating in the high-cost streaming business." Wedbush downgrades D.R. Horton to neutral from outperform Wedbush downgraded the homebuilder on "lower volume expectations." "We are downgrading DHI to NEUTRAL from OUTPERFORM and our PT moves to $96 from $104. The price cuts needed to maintain sales volume for F2Q23 and potentially F3Q23 may prove steeper than we previously expected."