Jon Najarian buys Qualcomm on unusual activity

CNBC "Halftime Report" trader Jon Najarian bought shares of Qualcomm, a maker of smartphone semiconductor chips, on Friday after spotting unusual activity in the options market.

Najarian is one of the top traders in CNBC Pro's Model Portfolio competition, up 4.5 percent on the year, beating the S&P 500, which is down 5 percent.

Here is what Najarian sees and why he thinks the stock can rally from here...