Traders are buying calls at a rapid pace lately on Dendreon Corporation (DNDN) and Halliburton Company (HAL), according to data from the International Securities Exchange (ISE). From a contrarian perspective, this rise in bullish speculation is intriguing. Currently, both DNDN and HAL are going through technical breakdowns.

Beginning with biotech titan DNDN, the stock has underperformed the broader S&P 500 Index (SPX) by nearly seven percentage points during the past 20 days. The shares were down 6.5% in one afternoon alone, extending a recent slump beneath pressure from their ten- and 20-day moving averages.

In fact, DNDN is currently on track to breach support at its ten-week moving average for the first time since January 1. The next potential backstop for the stock is at the round-number $40 level, a former technical ceiling that could switch roles to act as a floor.

Nevertheless, traders can't control their appetite for DNDN calls. The stock's ten-day ISE call/put volume ratio of 5.37 ranks in the 89th annual percentile, marking a near peak of bullishly biased options activity on the exchange.

Meanwhile, HAL sports a similarly bloated ten-day ISE call/put volume ratio of 3.57—in the 98th annual percentile—indicating that traders on this exchange have snapped up calls over puts at a faster pace just 2% of the time during the past year.

Based on this upbeat option activity, you might never suspect that HAL recently gapped below its 20-month moving average. The stock is sitting on a substantial year-to-date drop of 21.5%, and it's wallowing beneath the unrelenting pressure of its ten- and 20-day moving averages, just like DNDN.

However, there is one caveat: It's possible that traders are buying calls in order to hedge new short positions on HAL and DNDN. Nevertheless, the heavy call volume on these two stocks should raise the interest of contrarian traders. In their current condition, the last thing HAL and DNDN need to contend with is additional option-related resistance.

By Elizabeth Harrow, contributor, Schaeffer’s Trading Floor Blog