First up is manufacturing conglomerate Dover ( DOV). The $12 billion firm has been showing strong performance for the last six months and change, but now, a bearish double top setup points to an end to the bullish trend. >>5 Stocks Poised to Pop on Bullish Earnings The double top is a pattern that's formed by two swing highs that hit their heads at approximately the same price level. The sell signal comes on a breakdown below the near-term support level for shares, which was at $70. Dover's break below that level last week triggered a sell for this stock. Now it's a question of where this stock will be able to catch a bid again. Even though Dover's topping pattern isn't as symmetrical as the textbook example, the trading implications remain the same for this stock. The uptrend that's been in place since late October got broken earlier in April, and now there's an abundance of sellers as investors look to take gains while they can. Investors looking to enter a position in DOV should wait until shares can establish support again.