Volkswagen has another lawsuit on its hands related to the ongoing diesel-emissions scandal.

In addition to suits filed by hundreds of disgruntled customers and dozens of regulatory agencies in various countries, VW shareholders in Germany are now suing the company.

They claim Volkswagen violated German capital-markets law by not reporting developments concerning the diesel scandal quickly enough.

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It follows reports and much speculation regarding how much top Volkswagen officials knew about the use of "defeat device software" in diesel cars--and when they were tipped off about it.

VW considers the suit to be "without merit," the company said in a statement.

It says that top officials only became aware of the use of illegal "defeat device" software in September, when it was announced in a press conference by the U.S. Environmental Protection Agency (EPA).

2014 Volkswagen Passat TDI

2014 Volkswagen Passat TDI

Volkswagen's cheating was discovered in a study of vehicle emissions conducted by researchers from the International Council on Clean Transportation (ICCT) and West Virginia University.

And the VW statement discussing the German lawsuit revealed that a report on that study was prepared for then-CEO Martin Winterkorn in May 2014.

On May 23, 2014, a memo on the ICCT study was prepared for Winterkorn, and it was included in his "extensive weekend mail," the statement said.

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There is no evidence Winterkorn read that e-mail at the time, Volkswagen notes. He resigned in September just days after news of the scandal broke.

Winterkorn had also received a second memo on November 14, 2014, that mentioned the diesel issue as one of multiple items for his attention.

It included a cost estimate of 20 million euros (about $21 million) to rectify it in North America.

2015 Volkswagen Golf TDI SE

2015 Volkswagen Golf TDI SE

In October,  VW Group set aside 6.7 billion euros ($7.1 billion) to cover the costs of the scandal, a number many analysts have suggested is insufficient.

Finally, on July 27, 2015, "individual Volkswagen employees" discussed the issue "on the periphery" of a meeting at which Winterkorn and VW brand boss Herbert Diess were present, the company's press release said.

It goes on to say that it is not clear whether Winterkorn and Diess understood at the time that the "defeat device" software was illegal, and that Winterkorn asked for further clarification.

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He wasn't formally notified about the full extent of the situation until September 4, a day after Volkswagen representatives met with U.S. regulators, according to the statement.

This reconstruction of events comes from an internal report on the emissions scandal being assembled by investigative firm Jones Day.

VW says it will release "preliminary results" of the investigation at the end of April.


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