Hyperscalers' Cost of Capital Doubles to 10%, Raising the Bar for AI

Hyperscalers' weighted average cost of capital has more than doubled since 2023 — from 4% to 10% — according to Bank of America's Savita Subramanian. That number is now the minimum return threshold every dollar of AI infrastructure spending has to clear. And it's the quiet story behind Monday's market bounce.

What happened in markets today?

Stocks struggled globally as oil climbed to $108 per barrel. Asia was mixed, Europe declined, and U.S. futures pointed higher after Friday's tech-led selloff. Nasdaq futures rose strongly before the New York open — traders are betting last week's rout was overdone.

"Things are looking a lot cheerier than they were at the close on Friday. After yet another lurch lower for tech, buyers have once again appeared," Chris Beauchamp, chief market analyst at trading platform IG, told Fortune.

"Amid all the doom-laden commentary we saw last week, it is easy to forget that the S&P 500 was at a record high just two weeks ago. Last week looks more like a healthy rotation than the beginning of something more dramatic, no matter how much many bearish types would wish it otherwise," Beauchamp said.

The scorecard:

• S&P 500 futures up 0.47% this morning; the index fell 1.09% on Friday.
• Europe: Stoxx 600 down 0.78% in early trading; U.K.'s FTSE 100 down 0.87% before lunch.
• Asia: South Korea's KOSPI up 1.76%; Japan's Nikkei 225 down 0.62%; India's Nifty 50 down 1.19%; China's CSI 300 up 0.09%.
• Brent crude rose to $108 per barrel.
• Bitcoin traded at $82,769.

Today also marks the 39th anniversary of Black Monday, when the Dow Jones fell 22.6% in a single day.

Why did yields stop screaming?

The yield on the benchmark 10-year Treasury sat at 5.08% this morning, down from its recent peak of 5.3%. That pullback matters more than the equity bounce, because it was the yield spike — not a company-specific shock — that did the damage last week.

How bad did it get? According to a chart from Michael Hartnett's team at Bank of America, the market was pricing in risk similar to the Great Financial Crisis. That's the lens through which to read Friday's selloff: traders weren't dumping tech on earnings fears alone, they were repricing the risk environment itself.

A 22-basis-point drop in the 10-year won't undo that repricing. But it gives equity buyers enough room to step back in, which is exactly what Nasdaq futures showed this morning.

What does this change for AI capex?

Here's the practical question for anyone funding or analyzing AI buildouts. Subramanian puts it in plain Economics 101 terms.

"Economics 101 tells us that investing makes sense until returns on incremental invested capital (ROIIC) fall below the weighted average cost of capital (WACC). Inflation, real yields, credit events, increased regulations, equity supply outpacing demand are risks from here," she wrote in a note.

Read that carefully. In 2023, when hyperscalers could fund themselves at a 4% WACC, an AI project returning 6% created value. Today, at a 10% WACC, that same project destroys 4 cents on every dollar deployed. The economics of the identical investment have flipped without a single change to the technology or the demand.

Higher yields flow straight through the chain. Inflation, real yields, credit events, tighter regulation and equity supply outpacing demand are all on Subramanian's risk list — every one of them pushes the hurdle rate up or the achievable return down.

The market is watching this intensely. "Most of our equity meetings are 90% AI, 10% everything else. But they all boil down to the question above," Subramanian said. When institutional investors spend nine-tenths of a meeting circling one variable, that variable is the trade.

So what's the forward view?

Subramanian's forecast: the capex wave has further to run, but there might be a "marked shift in trend" next year if yields don't decrease. That's a conditional, not a call — the fate of the AI spending boom now rests on the bond market doing the work.

For practitioners, the sequence to watch is straightforward. If the 10-year keeps cooling from 5.08%, the WACC pressure eases and the current capex trajectory holds. If yields back up toward 5.3% or beyond, hyperscalers face a shrinking set of projects that clear a 10% hurdle — and the "marked shift" stops being a 2027 scenario.

Monday's equity bounce says traders think the worst is over. The bond market, not the Nasdaq, gets the final vote.