Privacy International, a London-based advocacy group, has singled out Google in a recent report as having an "entrenched hostility to privacy."

Although Google officials insist the company never passes along personal data to third parties, the report, titled "A Race to the Bottom – Privacy Ranking of Internet Service Companies," illustrates several concerns regarding the search giant.

Chief among the report's criticisms is Google's growing size with the recent DoubleClick acquisition. That deal still needs approval from U.S. regulators, but is expected to go through despite criticism from privacy advocates.

Google blasted the report's conclusions.

"We are disappointed with Privacy International's report, which is based on numerous inaccuracies and misunderstandings about our services," Nicole Wong, associate general counsel at Mountain View, California-based Google said in a statement.