Melt-Up

What It Is

A melt-up describes the phase of a rally where the driver of new buying stops being valuation or earnings and becomes the rally itself — price going up draws in more buyers, which pushes price up further. The term is deliberately the mirror of a melt-down: both describe a self-reinforcing move where positioning and psychology, not new fundamental information, are doing most of the work. It typically shows up after a rally has already run for some time, as the last holdouts capitulate into the trend.

Reading the Signature

Two observable traits mark a melt-up. The first is a steepening slope — the rate of gain accelerates rather than holding steady, producing the characteristic parabolic shape on a chart. The second is breadth behavior, and here the read is genuinely contested: a melt-up can either narrow, as the crowd concentrates into the names already leading, or broaden, as FOMO buying pulls previously lagging stocks along for the ride — both patterns have shown up in past melt-ups, and which one is present is itself part of the diagnostic.

Regime Information, Not a Sell Signal

The practical mistake is treating a melt-up as an automatic call to exit. A melt-up says the market has entered a high-participation, low-discipline phase — that is regime information, and regimes can persist longer than the fundamentals seem to justify before they end. It pairs naturally with elevated or falling VIX readings depending on whether the melt-up itself is orderly or erratic, and with the eventual relief-rally pattern on the other side of whatever correction follows. The honest position is to hold two things at once: the move is real while it is happening, and its late-stage character is exactly what makes it fragile.