Capital Economics is warning that the powerful shift underway in U.S. equities could signal that a long‑running stock market bubble will burst in 2027, ushering in years of upheaval in leadership across major indices.
In a Feb. 20 note, John Higgins, chief markets economist at Capital Economics, argues that the recent outperformance of small-cap, value and defensive stocks relative to large-cap, growth and cyclical names echoes patterns seen in the late stages of the dot‑com boom. “If the aftermath of the dotcom era is any guide,” Higgins wrote, “the bursting of the next bubble in the stock market—which we forecast will occur in 2027—might be followed by periods in which small-cap and value stocks outperformed their peers for a very long time.”
Seen in this light, Higgins continued, the latest rotation in stocks away from tech and toward more value-conscious sectors such as energy “could be a warning of trouble ahead” and a harbinger of more dramatic shifts to come.
Similarities to the dotcom era
So far this year, MSCI indices tracking small-cap, value and defensive sector stocks have each outperformed their large‑cap, growth and cyclical counterparts by roughly 10 percentage points on a total‑return basis, noted Capital Economics. The move is flattered by overlap among the groups. The rotation began quietly in late 2025 but has “gathered momentum” through the early weeks of 2026, even as the overall U.S. market remains elevated by historical standards.
Higgins cautions that, in the context of the post‑Global Financial Crisis era’s bullish run, the shift still “barely registers,” making it too early to declare a durable regime change. But he draws a pointed comparison with the run‑up to the 2000 crash, when U.S. small caps quietly began to outperform large caps about 11 months before the dotcom bubble burst. Back then, the turning point came in April 1999, after four years in which large-cap growth stocks had dominated as the bubble inflated.
One key difference this time is timing within the style spectrum. In the dot‑com cycle, value stocks only started to outperform growth meaningfully after the bubble had already burst. By contrast, in early 2026, value is already outpacing growth, which makes the current episode “a little bit different in that respect,” the report says.
The note downplays the role of immediate political or legal shocks in driving this year’s factor and size moves. Higgins does not expect the latest rotation in US equities to be “heavily influenced” by the recent Supreme Court ruling that President Donald Trump’s IEEPA tariffs are illegal, even if the administration seeks alternative ways to raise tariff revenue. The economic consequences of those efforts “may not be that large,” he adds, contrasting them with last year’s “Liberation Day” period, which triggered sharp swings in small‑cap versus large‑cap and value versus growth performance.
Instead, the firm sees market internals as the more important signal. The combination of elevated headline indices, growing investor attention to valuations and a leadership shift beneath the surface fits its broader thesis that US equities are in the late stages of a bubble. The emerging pattern, Capital Economics argues, is consistent with investors starting to probe more beaten‑down corners of the market and hedge against the risk that the mega‑cap growth trade unravels.
Differences from the dotcom era
The recent outperformance of small-cap, value and defensive stocks can be read as a late‑cycle warning, but it can also reflect a routine reassessment of risk and valuation rather than an impending crash. Similar rotations have occurred many times without a subsequent bubble burst; and in many cases, they are a healthy market reaction to what former Federal Reserve Chair Alan Greenspan—somewhat notorious for presiding over the inflation of the dotcom bubble—famously dubbed “irrational exuberance.”
The comparison with the dotcom era is compelling, but it is also selective. The late 1990s featured extreme valuations concentrated in a narrow slice of unprofitable tech, a backdrop very different from today’s mix of mega‑cap firms with robust earnings, dominant market positions and enormous cash flows.
A genuinely dangerous bubble typically requires a large disconnect between prices and underlying earnings, cash flows and balance sheet strength. Today’s leaders, especially in technology and AI‑related sectors, may be expensive, but a portion of that premium is supported by strong profitability, secular growth drivers and high returns on capital. Those fundamentals can justify elevated multiples and may allow earnings growth to “catch up” with valuations over several years.
For this story, Fortune journalists used generative AI as a research tool. An editor verified the accuracy of the information before publishing.
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