Apple, Micron and AI chipmakers add billions as market values surge

Investors kept rewarding the biggest names tied to artificial intelligence in May, but the surge looked less like a broad tech rally than a judgment on which companies can turn AI demand into real earnings. Apple, Micron Technology, Samsung Electronics and SK Hynix added a combined $1.97 trillion in market value, lifting Apple by $598 billion to $4.58 trillion, Micron by $512 billion to $1.09 trillion, Samsung by $481 billion to $1.10 trillion and SK Hynix by $377 billion to $1.34 trillion.

Apple’s gains were backed by a stronger operating picture than many of its peers. The Cupertino, California company reported fiscal second-quarter revenue of $111.2 billion for the quarter ended March 28, up 17% from a year earlier, with diluted earnings per share of $2.01, up 22%. Apple also announced a fresh $100 billion share buyback on April 30 and said demand for the iPhone 17 and MacBook Neo was strong. Its stock rose nearly 4% after the earnings update, helping convince investors that the company’s rally rested on more than sentiment.

Nvidia offered a similar mix of hard numbers and market enthusiasm. In May, the chipmaker forecast second-quarter revenue of about $91 billion, plus or minus 2%, above Wall Street estimates of about $87 billion, and unveiled an $80 billion share repurchase program. Chief executive Jensen Huang said the company has a broad base of customers and new products to support continued growth, underscoring how the AI buildout is still translating into order growth and pricing power for the sector’s most important supplier.

The gains were not evenly spread across the megacap landscape. Alphabet’s market value fell by $59.77 billion to $4.59 trillion, a reminder that the AI trade is not lifting every giant in lockstep. JPMorgan Chase and Walmart were the biggest decliners among the world’s 20 most valuable companies, reinforcing how concentrated the market’s enthusiasm has become around a narrow group of chipmakers and AI beneficiaries.

That concentration matters. SK Hynix and Micron both crossed the $1 trillion valuation mark in late May, showing how far the memory-chip rally spread beyond the biggest U.S. names. For investors, the message is clear: markets are still paying for AI as an earnings engine, not just a story. But with valuations clustered at the top and supply-chain limits still in view, any stumble in data-center demand, consumer spending or chip production could hit the market hard and fast.