Amazon ( AMZN 1.04%) is the fourth-largest company on the stock market by market capitalization, but it's way behind the top three -- Apple, Nvidia, and Microsoft, which have all traded the top spot over the past year and are all worth more than $3 trillion. Amazon's market cap is closer to $2 trillion, quite a wide gap.

Stocks are closing with solid gains as Wall Street puts the finishing touches on one of its best months of the year. The S&P rose 0.7% while the Dow Jones Industrial Average was up 188 points, or 0.4%.

On Monday, storied Swiss bank UBS Group initiated coverage of Arm's stock. Analyst Timothy Arcuri flagged the highly specialized AI stock as a buy, with a price target of $160 per share. That's 17% higher than the stock's most recent closing price.