The Electronic Privacy Information Center (EPIC) has become the latest group to speak out against Google's inclusion of data from the Google+ social network in web search results.
The group sent a letter to the chairman and commissioners of the US Federal Trade Commission (FTC) asking that the privacy and antitrust implications of the move be considered by the commission as part of its ongoing investigation into the company.
"Google's changes implicate concerns over whether the company prioritises its own content when returning search results," the group said in its letter to the FTC.
"Incorporating results from Google+ into ordinary search results allows Google to promote its own social network by leveraging its dominance in the search engine market."
Google announced the feature earlier this week as part of its "Search Plus Your World" platform, which seeks to integrate personally relevant information with web search results. The feature has been decried by rivals such as Twitter, which views the service as an unnecessary feature that would distort search results for users.
EPIC has been critical of social networking sites in the past. Last year, the group took aim at Facebook over the social network's ongoing attempts to reshape its user privacy protections and policies.
The group also squared off against Google in 2010 when it led the charge against the company's controversial Buss social network.
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