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:

• Morgan Stanley upgraded Block (XYZ) to Overweight from Equal Weight with a price target of $67, up from $65. The firm sees a "compelling" valuation at current share levels and low expectations for reaccelerated Square Seller growth.

• Cantor Fitzgerald upgraded Zscaler (ZS) to Overweight from Neutral with a price target of $250, up from $220. Improved execution, "solid" near-term checks, and the expectation that accelerating billings, revenue growth, and margin expansion can support a re-rating of shares moving through fiscal 2025, the firm tells investors in a research note.

• Citi upgraded Ross Stores (ROST) to Buy from Neutral with an unchanged price target of $146. The firm expects Ross to benefit from the current environment and tariff disruptions, leading to better traffic, sales and margins.

• Citi upgraded TJX (TJX) to Buy from Neutral with a price target of $140, up from $128. Tariffs are likely to create "significant disruption" in the market, but the firm views off-price as "defensively positioned" in the near-term, and well positioned for continued growth in the long-term as other retailers "struggle and close stores."

• Wolfe Research upgraded Fastenal (FAST) to Peer Perform from Underperform without a price target ahead of the Q1 report. The firm believes Fastenal's consensus estimates "look reasonable."

Top 5 Downgrades:

• HSBC downgraded Nvidia (NVDA) to Hold from Buy with a price target of $120, down from $175. Nvidia's share price is down 26% since its previous peak in January, notes the firm, which sees limited GPU pricing power going forward that caps earnings upside potential until opportunities evolve in robotics, autos and AI markets.

• BofA double downgraded Lyft (LYFT) to Underperform from Buy with a price target of $10.50, down from $17.50, citing what the firm views as "substantial AV risk," especially Waymo's (GOOGL) rapid expansion in San Francisco and Los Angeles and Lyft's lack of scalable autonomous vehicle partnerships launching in the near-term.

• BofA downgraded RxSight (RXST) to Underperform from Buy with a price target of $22, down from $36, after the company pre-announced a 5% Q1 revenue miss and lowered 2025 revenue guidance by 12% at the midpoint.

• Citi downgraded RH (RH) to Neutral from Buy with a price target of $200, down from $437. President Trump's reciprocal tariff announcement is worse than expected and "significantly changes" Citi's view of the broadlines and hardlines sector.

• Citi downgraded Best Buy (BBY) to Neutral from Buy with a price target of $70, down from $93. Following President Trump's reciprocal tariff announcement, the firm says its biggest concerns include rising recession risk probability and a slowdown in consumer spending.

Top 5 Initiations:

• Susquehanna initiated coverage of SanDisk (SNDK) with a Positive rating and $70 price target following the company's spinoff from Neutral-rated Western Digital (WDC).. Despite volatile macro trends and uncertainties associated with tariffs, the firm's Positive rating reflects an "attractive valuation."

• KeyBanc initiated coverage of Element Solutions (ESI) with an Overweight rating and $29 price target. The firm expects the company's EBITDA growth to accelerate to high single-digits over the next three years, compared to the mid-single-digit range historically.

• Canaccord initiated coverage of Talkspace (TALK) with a Buy rating and $5 price target. The firm sees a "massive revenue runway" within the company's base of covered lives.

• Janney Montgomery Scott initiated coverage of Equity Bancshares (EQBK) with a Neutral rating and $42 fair value estimate. The firm, which highlights the bank's "sound fundamentals" and potential for strategic acquisitions, believes the shares should trade at a "modest premium to the peer group."

• H.C. Wainwright initiated coverage of Kairos Pharma (KAPA) with a Buy rating and $12 price target. The company's oncology pipeline "could unlock the immune system" to overcome cancer resistance in metastatic castration resistant prostate cancer and beyond, the firm says.