Volkswagen (VLKAY) chairman Hans Dieter Pötsch has become embroiled in the German prosecutor's probe into whether company executives withheld key information as the emissions scandal of September 2015 broke.
The more-than year-long probe by the Braunschweig public prosecutor relates to whether executives manipulated the market by not disclosing the likely financial damage of the scandal in good time.
The prosecutor said when announcing the probe, that the "duty to disclose" could have arisen some time before Sept. 22, the date when VW first raised the emissions issue with investors.
VW Sunday came out in defense of its chairman, who was chief financial officer when the scandal erupted.
"Based on careful examination... the company reaffirms its belief that the Volkswagen board of management duly fulfilled its disclosure obligation under German capital markets law," VW said.
The news came closely on the heels of a press report suggesting authorities in the U.S. have found that Audi cars carried emissions cheating software as recently as this May that differed to that found in the initial scandal.
The Bild am Sonntag reported on Sunday that the California Air Resources Board discovered that Audi cars contained software that could detect when cars are under test conditions and then conceal the true level of engine emissions.
VW did not immediately respond to requests for comment.
VW investors appeared to take the news in their stride. The stock rose by 0.4% in the early hours of the European session, to trade at €119.1 ($130.1). They are down by 11.3% for the year to date.