Hyperscaler AI capex has crossed $300B in annual run-rate spending. That's not a fad; it's the largest sustained corporate investment cycle since the smartphone build-out of 2007–2012. Every earnings season is now a referendum on whether that spend is paying off — and whether it'll keep growing.
Who's spending the money
Four hyperscalers — the largest U.S. cloud and consumer-internet platforms — account for the bulk of AI capex. Their capex guides are published with earnings and are the single most-watched number on the print. A raise is bullish for the entire supply chain; a cut signals the spending cycle is maturing.
Who's getting paid
Three tiers of beneficiaries:
1. Compute (advanced GPUs, accelerators, networking silicon). Highest-margin, highest-multiple, most exposed to a single customer concentration. 2. Infrastructure (memory, optical, power, cooling, data-center REITs). Lower multiples, broader customer base, slower but steadier earnings revisions. 3. Software and applications building on top of the compute. Furthest from the capex but closest to monetization — the segment where the next 5x returns will likely come from once revenue catches up to spend.
What earnings season will reveal
Three questions to ask of every AI-exposed name this season:
1. Is capex guidance higher, flat, or lower than last quarter? 2. Is the company seeing revenue growth that matches the capex narrative, or is it still a pure cost story? 3. Are operating margins holding, or is competition compressing pricing?
When all three trend favorably, the multiple expands. When capex is up but revenue and margins disappoint, the multiple compresses fast — even on a headline beat.
The bear case nobody wants to write
Every capex super-cycle ends with overcapacity. The 1999 telecom build-out, the 2007 housing boom, the 2014 shale boom — all featured years of capex growth that ran past demand. The AI cycle will end the same way; the only question is when. Watch for: hyperscalers walking back capex guides, GPU lead times shortening, and average selling prices for accelerators slipping. None of those signals are flashing yet — but the day they do, the entire complex re-rates lower.