Take a look at some of Monday's midday movers:
Merck & Co. - The pharmaceutical giant fell after a mid-stage trial showed its attempt to shorten hepatitis C treatment to four weeks by adding Gilead's Sovaldi to its own treatment showed disappointing results. Gilead Sciences rose on the news.
Comcast - The company and other providers of internet services including Time Warner Cable, Charter Communications and Cablevision Systems fell after President Barack Obama took a strong stand on net neutrality.
GoPro - The maker of action cameras slumped after filing for an $800 million offering.