Market Insider

Qualcomm shares plunge after downgrade, lawsuit

Qualcomm Inc. CEO Steve Mollenkopf speaks during a keynote address at CES 2017 on January 6, 2017 in Las Vegas, Nevada.
Ethan Miller | Getty Images

Shares of Qualcomm tumbled Monday after a downgrade on the back of potential legal troubles.

Apple announced a $1 billion lawsuit against Qualcomm on Friday over royalties.

On Monday, Nomura's Instinet lowered its rating on the chipmaker's stock to neutral from buy on concerns about how the scrutiny on royalties would affect Qualcomm's deal to acquire NXP Semiconductors.

Qualcomm shares dropped more than 11 percent in midday trade, tracking for its biggest decline since Nov. 5, 2015, when shares fell 15.25 percent.

Shares of NXP Semiconductors traded more than 1 percent lower. The iShares PHLX Semiconductor ETF (SOXX) traded 0.5 percent lower.

Qualcomm did not immediately respond to CNBC's request for comment.

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