Volkswagen Chairman Hans Dieter Poetsch and Chief Executive Matthias Mueller were aware of the use of illegal emissions-control software in the company’s cars in the United States, according to a report. Former chief executive of Volkswagen Martin Winterkorn had informed the executive board two weeks before the news of defeat devices in VW cars was made public, a report in German weekly Bild am Sonntag said. Poetsch was VW’s finance chief then, while Mueller was the CEO of Porsche, Reuters reported.

Winterkorn, who had resigned within a week of the scandal coming to light, had briefed the company’s executive board that the automaker had admitted the use of defeat devices to United States authorities, the report said. Investors and analysts have come down heavily on Poetsch for not keeping shareholders in the know. A spokesperson said in an emailed statement, “Volkswagen is convinced to have fully complied with the requirements set out in the securities law...and categorically declines comment on contents of management board meetings.”

Winterkorn was forced to resign once the manipulations were revealed on September 20, 2015, and the company’s market value dropped by billions of euros. However, the carmaker defended its course on March 2, claiming it had no idea how expensive it would be to undo the system till the US Environmental Protection Agency released its statement on September 18. Volkswagen said it will publish results of an investigation led by US law firm Jones Day into the matter in the second half of April.