AI demand, earnings optimism lift tech giants' market value in May

June 2 (Reuters) - The world's most valuable technology companies with the exception of Alphabet added billions of dollars in market value in May, as upbeat earnings outlooks and strong demand for AI chips fuelled a rally in their shares.

Apple, memory chipmakers Micron Technology, Samsung Electronics and SK Hynix led the gains, adding $598 billion, $512 billion, $481 billion and $377 billion, respectively, in market value. Their valuations rose to $4.58 trillion, $1.09 trillion, $1.10 trillion and $1.34 trillion, respectively.

In late April, Apple pointed to strong demand for its flagship iPhone 17 and MacBook Neo and announced a fresh $100 billion share buyback.

Samsung reported an eightfold jump in first-quarter operating profit in April, while Micron drew analyst upgrades after saying its 2026 high-bandwidth memory (HBM) chips were already sold out and next-generation HBM4 products were in production.

Microsoft and Nvidia also gained, with their market values rising by $315 billion and $276 billion, respectively, to $3.35 trillion and $5.11 trillion.

Nvidia forecast second-quarter revenue above expectations in May and announced an $80 billion share repurchase programme.

Bucking the trend, Alphabet's market value dropped $59.77 billion to $4.59 trillion.

In the world's 20 most valuable companies including other sectors, banking group JPMorgan Chase and retailing giant Walmart saw the biggest falls in market capitalisation in May, by $130.47 billion and $37.3 billion, respectively, to $921 billion and $802 billion.

(Reporting by Gaurav Dogra in Bengaluru; Editing by Emelia Sithole-Matarise)