A head-and-shoulders top with two or more shoulders on a side, all sharing one flat neckline.
Complex (multiple) head and shoulders have extra shoulders, and sometimes two heads. Edwards & Magee observed that they tend toward symmetry: two left shoulders often mean two right shoulders. The pattern completes on a close below the shared neckline.
Rare. A loosely drawn complex head and shoulders is easy to imagine in any range, so the neckline rules are strict.
How we define it
7 or 9 alternating swings of at least 2 ATR: one head and at least three shoulders, with two on at least one side
Neckline: all reaction lows within 3% (or 15% of the height) of each other and at least 3 of them on the line; no close below it before the breakdown
Head clearly above every shoulder; shoulders at 30-85% of the head height and within 25% of each other
Minimum length: 2 months on 1D, 3 months on 1W, 10 days on 4H
Breakout (up) / breakdown (down): the first candle close beyond the boundary by at least 3% on 1D and 1W (1.5% on 4H)
Failed breaks: a breakout or breakdown that closes back inside the boundary within 6 candles on 4H, 5 on 1D or 3 on 1W is removed from the list
Trend filter: breakouts only above the 200-period EMA (40-week EMA on 1W), breakdowns only below it
Watchlist: the pattern is complete but unbroken and price is within 3% (or 1 ATR, at most 6%) of the boundary