Pfizer ( PFE), on the other hand, is a good example of what happens when a stock falls through trendline support. The pharma giant spent most of 2013 in an uptrend, climbing around 24% from the first trading session in January until the end of April. But the break below support in mid-May signaled that PFE was due for lower levels. >>5 Buy Signals From the Health Care Sector Now Pfizer is testing trendline resistance, bumping up against the upper-end of a downtrending channel after rallying for a handful of days when the broad market failed to. That sounds like a selling opportunity for all of the reasons that Chevron's chart is a buy. But PFE gets the same caveat that CVX does before it makes sense to put real money on the line: Wait for a bounce. The 50-day moving average is right above the top of the channel on Chevron's chart; that's where I'd recommend keeping a protective stop.