Activist hedge fund JANA Partners is going after Qualcomm

Activist investor Barry Rosenstein, the founder of $11 billion JANA Partners, disclosed a huge stake in wireless technology developer giant Qualcomm.

The Wall Street Journal is reporting that JANA Partners now owns about $2 billion worth of Qualcomm's stock making it the fund's largest position. Qualcomm has a market cap of more than $114 billion.

According to the Journal, which cites an investor letter, JANA is urging the company to spin off its chip business from its patent-licensing business. JANA also wants the company to cut costs and accelerate share repurchases, the Journal reported.

Shares were up 4.8% in the pre-market. The stock has lagged this year. Shares of Qualcomm are down more than 6% since the beginning of 2015.

Here's a chart of Qualcomm's performance this year: