Apple and Microsoft Cross $4 Trillion Mark Amid AI Boom

Apple AAPL and Microsoft MSFT just hit a new milestone, both crossed the $4 trillion market cap mark on Tuesday, joining Nvidia NVDA in one of the most exclusive clubs in market history. The achievement underscores just how dominant Big Tech has become, especially as the AI boom continues to reshape investor sentiment.

It's not just these two making headlines. Alphabet GOOG notched a $3 trillion valuation last month, while Meta META hit $2 trillion in August. Together with Amazon AMZN and Tesla TSLA, the so-called Magnificent 7 now make up roughly one-third of the entire S&P 500 (SP500), an unprecedented concentration of market power.

The rally isn't fueled by hype alone. Apple's product ecosystem, Microsoft's Azure and Office suite, Amazon's AWS, and Google and Meta's ad engines continue to churn out massive profits. Add to that deep cash reserves and aggressive AI investment, and these companies have become the backbone of the next phase of technological growth.

Investors are betting that as AI becomes more fully monetized, the biggest names in tech will not only lead the revolution, they'll own it.