Big Tech’s record spending on artificial intelligence infrastructure is raising questions on Wall Street about debt levels and returns on investment.

Microsoft, Alphabet, Meta and Amazon are pouring hundreds of billions of dollars into data centres and chips. The scale of the buildout is unprecedented in corporate history.

To fund the expansion, several giants have turned to bond markets, issuing debt at a pace rarely seen from cash-rich technology companies. Credit analysts are watching leverage ratios closely as borrowing climbs.

Supporters argue the spending is necessary to capture the AI opportunity, comparing it to the railroad and telecom buildouts of earlier eras. They say demand for computing power shows no signs of slowing down.

Sceptics warn that if AI revenues disappoint, the industry could face a painful reckoning. For now, investors continue to reward the spending, with technology stocks trading near record highs and executives doubling down on their ambitious plans.