The European Commission and the U.K. Competition and Markets Authority each said they were opening competition inquiries into social-media giant Facebook's
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advertising services. The European Union said it's looking to see whether Facebook violated EU competition rules by using advertising data gathered from advertisers in order to compete with them in markets where Facebook is active such as classified ads. The formal investigation will also assess whether Facebook ties its online classified ads service "Facebook Marketplace" to its social network. The U.K. probe also mentioned Facebook Dating, a dating profile service launched in Europe in 2020. The two agencies said they would work closely with each other. Facebook shares have climbed 19% this year, topping the 12% rise for the S&P 500.