Big Tech's $236B AI Debt Binge Losing Investor Appeal

Hyperscalers are caught in an escalating capital cycle: the sheer scale of AI data center buildouts has forced them away from relying purely on cash flows and into the bond market for funding. Morgan Stanley's projection of $570 billion（約91兆円） in AI bond issuance by end of 2026 underscores the magnitude of this shift. What makes this moment significant is the divergence between equity and bond investor sentiment—stock buyers initially rushed to snap up the offerings (as evidenced by early SpaceX stock enthusiasm), but bond investors, who prioritize capital preservation and near-term cash flow, are signaling caution through lower demand and wider credit spreads.

This caution is already visible in concrete metrics: the cover ratio collapse from 5x to 2x in just six months suggests a sharp erosion in appetite. SpaceX, while not a traditional hyperscaler, illustrates the broader pattern—its $29 billion（約4.6兆円） long-term debt now trades at a 1.62-percentage-point premium over Treasuries, placing it in junk territory despite the stock's initial rally. Bond investors' skepticism matters because they are typically early detectors of financial stress; equity investors who ignore these signals may be exposed to a repricing if the data center investments fail to generate expected returns quickly enough to service the mounting debt.