Facebook (META -10.25%) is testing out new ways to target ads toward its users in a way that appears promising -- but is also already stirring up controversy. The social networking site is now allowing advertisers to use user phone numbers and email addresses -- if that data is volunteered on one's profile -- to target ads, according to a Wall Street Journal report. The experimental ad-targeting strategy will also involve data from users' browsing history on other Internet sites.

So far the new method has proven effective, with $1 spent on Facebook corresponding to an additional $3 in sales with nearly three quarters of the companies who've employed the strategy, the Journal reports. Needless to say, privacy advocates are not enthused, and the Electronic Privacy Information Center (EPIC) filed a complaint with the Federal Trade Commission last week. EPIC maintains that Facebook isn't playing fair, changing advertising procedure by beginning to include outside browsing information without user consent, the report said. Facebook, for its part, asserts that the experimental method is entirely legal, and has emphasized that it's not sharing the identities of the people associated with the new data points.

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