German regulators Tuesday hit Porsche with a $600 million (535 million euro) fine, for its role in selling cars powered by diesel engines designed by Audi that failed to comply with European emissions requirements.

The cars, including the Cayenne and Panamera, used a 3.0-liter diesel V-6, exceeded European emissions standards for oxides of nitrogen, which contribute to smog.

READ THIS: Audi to pay $927 million fine over diesel scandal in Germany

An investigation the regulators conducted found that Porsche employees turned a blind eye to the emissions cheating starting in 2009. In a release announcing the fine, Porsche emphasized that investigators found the negligence "several levels below" executive positions.

The fine represents the last action against Porsche, and one of the last against VW, to close out the legal repercussions of the larger VW emissions cheating scandal. In September, Porsche announced that it will stop selling diesels altogether as it focuses on developing and selling new electric models such as the new Taycan electric performance sedan due out late this year.

READ MORE: German prosecutors find collusion between automakers over diesel emissions

Audi was fined 800 million euros (about $927 million) last October over its leading role in the diesel emissions cheating scandal, and last month in a separate case triggered by the ongoing diesel emissions investigations, European Union regulators found that German automakers colluded to withhold the most effective emissions control systems from European consumers.

Daimler, which builds Mercedes-Benz models, does not expect to be fined in that case, because it drew European investigators' attention to the issue. BMW says it will fight the charges in court but set aside $1.1 billion in case it needs to pay the fine.