Broadening Formation, Right-Angled and Descending

Core idea

The right-angled and descending broadening formation has a horizontal top trendline (a ceiling of recurring resistance) and a down-sloping lower trendline along progressively lower minor lows. Price ping-pongs between the two until it closes outside one of them. The pattern favors upward breakouts about twice as often as downward ones and ranks mid-list for post-breakout performance — neither a star nor a dud. The structural story is supply: a known seller defends the horizontal top, while increasingly nervous holders mark their stops lower along the bottom edge.

The two ingredients

A valid pattern requires (1) at least two — preferably three — minor highs touching the same horizontal price level, and (2) at least two minor lows touching a descending trendline. Five total touches is Bulkowski's working minimum: three on one line, two on the other. Touches must be at true minor highs or lows; price slicing through a line at the start or end of the pattern doesn't count.

Why volume drifts up

Unusually for chart patterns, volume tends to rise over the formation's length, often mimicking the price swings. The widening price range pulls in more participants on each oscillation — momentum traders on the upswings, stop-hunters on the downswings — until one side overwhelms the other and the pattern resolves.

Why it matters

Pure shape-matching gives you a binary outcome: it's a pattern or it isn't. The descending broadening adds a third state — the partial move — which is one of the most useful preemptive signals in technical analysis. When price leaves a trendline, makes a half-hearted attempt at the opposite line, fails to touch it, and curls back, the next breakout is almost always in the direction of the failed attempt's reversal and happens immediately, without another full crossing of the pattern. That lets a disciplined trader take a position before the breakout confirms.

Key takeaways

Mental model

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Practical application

Trading the partial-move signal

Measure rule for targets

The measure rule is the pattern height (formation high minus low) added to the breakout price for upward breakouts, or subtracted for downward ones. Bulkowski reports the measure rule for descending broadening formations works less reliably than for tighter patterns — treat it as an aspirational target, not a stop-loss anchor.

Example

Consider a software stock trading in a $40-44 range for two months after a strong run-up. Four times in eight weeks price tags $44 and gets sold; meanwhile the lower swings print at $42, then $41, then $40 — a descending lower trendline. You count: four touches at $44 (top), three at the descending bottom. Pattern established.

In the ninth week, price leaves the bottom at $40 and rallies to $42.80 — short of the $44 top. Selling resumes. Price curls back down toward $42. This is your partial-rise signal: an immediate downward breakout is likely. You short at $41.50 with a stop at $44.20 (a hair above the top). Two days later price breaks below the descending lower trendline at $40.50 and drops to $36.

If instead the pattern had ended with a partial decline — leaving the top at $44 and bottoming at $41.50, never reaching the lower trendline at $40 — the opposite trade applies: buy on the curl-back toward $44 with a stop just below the failed low.

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