First Solar downgraded, Fortinet upgraded: Wall Street's top analyst calls

The most talked about and market moving research calls around Wall Street are now in one place. Here are today's research calls that investors need to know, as compiled by The Fly.

Top 5 Upgrades:

Barclays upgraded Zillow Group(ZG) to Equal Weight from Underweight with a price target of $72, up from $66. The firm believes a lot of downside risks are priced into shares.
Rosenblatt upgraded Fortinet (FTNT) to Buy from Neutral with a price target of $100, up from $85, ahead of the Q4 report on February 5. Recent channel checks with five resellers point to a "meaningful inflection" in demand for Fortinet, the firm tells investors in a research note.
Benchmark upgraded Littelfuse (LFUS) to Buy from Hold with a $360 price target. Following a "strong" Q4 report and upbeat outlook as the demand backdrop expands across the business, the firm notes that much of its prior concerns over visibility and persistent inventory burn are subsiding.
Morgan Stanley upgraded Cencora (COR) to Overweight from Equal Weight with a price target of $400, up from $361. The firm says the company has positioned itself as a leader in specialty which will be "amplified" by the acquisition of the majority stake in OneOncology.
Chardan upgraded Korro Bio(KRRO) to Buy from Neutral with a $15 price target following the analyst day. The firm says the company has "turned the page." Piper Sandler also upgraded Korro Bio to Overweight from Neutral.

Top 5 Downgrades:

BMO Capital downgraded First Solar(FSLR) to Market Perform from Outperform with a price target of $263, down from $285. The firm "initially dismissed as aspirational" Tesla (TSLA) CEO Elon Musk's remarks about potentially building a significant vertically integrated solar photovoltaic modules manufacturing base to self-generate, but Musk's remarks during Tesla's earnings call suggest "this is likely to become a bona fide effort" in the next few quarters.
Wells Fargo downgraded Omega Healthcare(OHI) to Equal Weight from Overweight with a price target of $45, down from $48. The firm views the stock's valuation as full at current levels.
Piper Sandler downgraded Prosperity Bancshares(PB) to Neutral from Overweight with a price target of $74, down from $77, as the firm believes the five-year tangible book value per share earn-back on Stellar Bancorp (STEL) deal will keep investors on the sidelines.
Raymond James downgraded Stellar Bancorp to Market Perform from Outperform without a price target. The firm cites the pending merger with Prosperity Bancshares for the downgrade.
Morgan Stanley downgraded Amcor (AMCR) to Equal Weight from Overweight with a price target of $46, down from $57.50, citing negative organic volume momentum despite Berry acquisition integration synergies being on track and an "attractive valuation."