Bump-and-Run Top: Definition, How to Trade, and Example

What Is a Bump-and-Run Top?

A bump-and-run top, sometimes called a bump-and-run reversal (BARR), is a bearish chart pattern that captures the lifecycle of an overextended trend. It was popularized by Thomas Bulkowski, who identified its three distinct phases: the lead-in, the bump, and the run.

The lead-in phase is a gentle, orderly uptrend with a moderate slope. Then the advance accelerates. The bump phase begins when the slope of the advance steepens dramatically - price pulls away from the lead-in trendline, often going parabolic. Volume may surge as euphoria and speculative buying drive the stock to unsustainable levels.

Finally, the bump exhausts itself. Price rolls over, falls back toward the lead-in trendline, and then breaks through it. This is the run phase - the rapid decline that follows the trendline break.

How a Bump-and-Run Top Works

The pattern works because the bump represents a departure from sustainable price appreciation. During the lead-in phase, the trend is supported by steady buying. During the bump, the advance becomes self-reinforcing: rising prices attract momentum chasers, media attention brings in retail buyers, and short-covering adds fuel.

The key insight is that the lead-in trendline represents the market's genuine rate of appreciation. When price deviates far above this line during the bump, it creates a gap between reality and speculation. Eventually, gravity wins.

The break of the lead-in trendline is the signal. Once price falls through the line that supported the original trend, all the gains from the bump phase are at risk. The run phase is typically fast and one-directional.

How to Identify a Bump-and-Run Top

The bump-and-run top has specific geometric requirements.

• The lead-in phase should last at least several weeks, with a moderate, steady upward slope.
• The lead-in trendline should have at least two clean touchpoints.
• The bump begins when the slope of the advance steepens sharply - at least twice the lead-in slope.
• The bump's height should be at least twice the lead-in height.
• Volume often spikes during the bump and declines as the bump rolls over.
• Confirmation requires a decisive close below the lead-in trendline.

How to Trade a Bump-and-Run Top

The primary entry is a short position on a confirmed break below the lead-in trendline. Some traders wait for a retest of the broken trendline from below for a tighter stop.

The stop loss goes above the bump's high for a conservative approach, or above the most recent swing high in the rollover for a tighter stop.

The textbook target is the bump height projected downward from the break of the trendline.

• Entry: short on a confirmed close below the lead-in trendline.
• Stop (conservative): above the bump's peak.
• Stop (aggressive): above the most recent swing high in the rollover.
• Target: the bump's height projected down from the trendline break.

Limitations and Pitfalls

The bump-and-run top fails roughly 36% of the time. In these cases, price breaks below the lead-in trendline briefly and then recovers.

The hardest part is identifying the lead-in trendline correctly. If you draw the trendline too steeply, the bump looks smaller. If too shallowly, you enter short prematurely.

A common emotional mistake is shorting during the bump rather than waiting for the trendline break. Bumps can extend far beyond what seems reasonable.

Finally, the run phase can be interrupted by dead-cat bounces that whipsaw traders with tight stops.

Example

Imagine a stock that trends gently from $30 to $40 over four months, forming a clean lead-in trendline. Then it rises from $40 to $58 in three weeks on surging volume. The bump height above the lead-in trendline (near $42 by the peak) is $58 - $42 = $16.

After the peak, the stock rolls over to $48, bounces to $52, drops to $44, and closes at $41 - breaking below the lead-in trendline (near $43). A short entry at $41 with a stop above $52 risks $11 per share. The target is $43 - $16 = $27, offering $14 of downside. With a tighter stop at $44, the risk drops to $3 for the same $14 target - a 4.7:1 ratio.

Bottom Line

The bump-and-run top is a pattern about overextension and its consequences. The lead-in phase shows what the stock can sustain; the bump shows what it cannot. When the bump fails and price breaks the lead-in trendline, the reversal is often swift. Trade it patiently - wait for the trendline break, not the peak of the bump.