Overview
- Jeremy Grantham told CNBC on June 26 that the U.S. market is at record expense relative to GDP and that a reversion to trend could produce a peak-to-trough drop he estimates may be closer to 70 percent.
- Recent market turbulence has punctuated the debate, with large swings in chip and tech shares, Korea’s KOSPI and the SOX index plunging and headlines such as Apple raising device prices and SpaceX planning a $25 billion bond issue.
- Valuation measures cited by critics include a market-cap-to-GDP ratio near 235% and an elevated CAPE, and analysts point to massive AI capital spending by mega-cap firms as a key driver of concentrated value.
- Major asset managers and banks dispute the bubble thesis, arguing that sustained earnings, productivity gains from AI and disciplined capital allocation could justify high prices if corporate profits materialize.
- Analysts warn of tangible risks if sentiment flips: higher corporate borrowing and circular financing could amplify losses that reach retirement accounts, hiring and household spending, and the Fed’s changed communications make markets more sensitive to shocks.