German firms file anti-trust complaint against Apple
"I can confirm we have received the complaint which we are now examining," a spokesman for Germany's Federal Cartel Office told AFP.
From this week, Apple will require app makers to tell users what tracking information they want to gather and get permission to do so.
Because many users are expected to refuse to grant such permission, the companies fear their ad income will be depleted.
The move by the US tech giant has sparked a major rift with Facebook and other tech rivals which rely heavily on digital ads.
Thomas Hoppner of law firm Hausfeld, which is representing the plaintiffs, told AFP his clients believed ATT would lead to an around 60-percent drop in revenue.
Apple CEO Tim Cook defended ATT in a recent interview: "The principle is that the individual should be in control over whether they're tracked or not; who has their data."
The company said Monday in a statement that the privacy feature would give users more choice while keeping a level playing field among competitors.
"These rules apply equally to all developers — including Apple — and we have received strong support from regulators and privacy advocates for this new feature," the company said.
Apple rejected the allegations at the time as "patently false", saying that "privacy is built into the ads we sell on our platform with no tracking".