Goldman has turned out strong performance in 2012, rallying more than 30% since January while the broad market has only earned around a third of that. But a head and shoulders top in shares points to a decline in shares. The head and shoulders is a pattern that indicates exhaustion among buyers -- it's formed by two swing highs that top out at around the same level (the shoulders), that are separated by a higher high (the head). A breakdown below the neckline is the sell (or short) signal for GS.
Momentum is adding some extra confirmation to this setup too. Fourteen-day RSI had been in an uptrend along with price, but the RSI uptrend broke back when the left shoulder was formed, and it's been trending lower ever since. Extra confirmation is just that, though -- wait for price to move below the $113 neckline before selling.