MENLO PARK, CA - MAY 18: A 'like' sign stands at the entrance of Facebook headquarters May 18, 2012 in Menlo Park, California. The eight-year-old social network company listed their initial public offering on NASDAQ Friday morning at $38 a share and a valuation of $104 billion, making its IPO the third largest in U.S. history after General Motors and Visa. (Photo by Stephen Lam/Getty Images)
	MENLO PARK, CA - MAY 18: A 'like' sign stands at the entrance of Facebook headquarters May 18, 2012 in Menlo Park, California. The eight-year-old social network company listed their initial public offering on NASDAQ Friday morning at $38 a share and a valuation of $104 billion, making its IPO the third largest in U.S. history after General Motors and Visa. (Photo by Stephen Lam/Getty Images)

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    Did Facebook study go too far?

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Did Facebook study go too far?

CNN's Laurie Segall explains how big tech companies are using your personal information and why.

Did Facebook study go too far?

CNN's Laurie Segall explains how big tech companies are using your personal information and why.