Meanwhile, things are starting to look "toppy" at Canadian Pacific Railway ( CP), thanks to a double top pattern that's been forming since early March. Like SXL, Canadian Pacific has enjoyed a stellar run so far in 2013, up close to 28% on the year -- and more than 41% in the last six months. But the double top signals a sell in CP on a move through $117. >>5 Huge Stocks to Trade: Must-See Charts 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 is right at $117. Obviously, CP is still a far way away from falling through that breakdown level at this stage in the game, but it's worth paying close attention to that $117 price at this point. It's the make-or-break level for this high-flying transport stock. Investors looking to enter a position in CP should wait until shares can establish support again. Canadian Pacific's death warrant isn't signed yet - remember, the stock doesn't become toxic until it falls through $117. The breakout above the upper bound of Top 1 negates the downside pattern.