Daimler says CEO Dieter Zetsche and its executives acted correctly in the appointment of a new lobbyist. Daimler executives are under investigation for suspicion of “granting undue advantage” to German Chancellor Angela Merkel’s former aide, Eckart von Klaeden, who has joined the carmaker as a lobbyist.

The move comes after Der Spiegel reported that Klaeden met with Daimler representatives while still in politics when he had access to three confidential government papers on the European Union’s planned regulation of auto emissions.

Germany last month blocked an agreement among EU member states to cap car emissions, arguing the plan would cost jobs and hurt its premium carmakers BMW, Audi and Mercedes-Benz, a unit of Daimler.

A probe into granting undue advantage is targeting executives at Daimler,” Berlin prosecutor’s office said on Friday. The investigation of top managers is a logical part of the probe, Martin Steltner, a spokesman for Berlin prosecutors, said. He declined to identify any board members or say how many are under investigation.

“It’s not illegal if a government official changes jobs and joins a company as a lobbyist,” Steltner said. “It would be illegal if the official did something in favor of the company while still in office in the expectation that would somehow pay off after he moved over. We have to review whether that was the case.”

Daimler said it would cooperate with authorities and said it remained convinced that its executives acted correctly. The company declined to elaborate further due to the ongoing investigation.

Germany’s WirtschaftsWoche magazine reported earlier that the probe was targeted at CEO Dieter Zetsche. Zetsche was not immediately available to comment on Friday.

Klaeden, a former treasurer of Merkel’s Christian Democrats who spent the last four years in a senior chancellery role, quit the government after Germany’s September 22 national elections to take up the position of chief political lobbyist at Daimler. Klaeden was also not immediately available for comment.

“It’s a completely normal procedure that prosecutors start investigations because an anonymous complaint was filed,” Daimler said in a statement on Friday. “We have no doubts at all about the integrity of Mr. Klaeden.”

A spokeswoman for Merkel declined to comment. Von Klaeden’s tasks in the chancellery “didn’t include facilitating, preparing or let alone make decisions related to the automotive industry,” Steffen Seibert, Merkel’s chief spokesman, told reporters on Nov. 4.

The investigation by the Berlin prosecutors’ office was triggered by an anonymous tip.

Von Klaeden has contacted prosecutors through his lawyer and is “fully” cooperating, he said in an e-mail on Nov. 3, saying he was confident that the allegations will be completely cleared.