Continental, a German tire and automotive supplier, said it was investigating the theft of company data as part of a high priority cyberattack, but declined to comment on media reports that hackers had sold the information.
According to the German business newspaper Handelsblatt, hackers published a list of data on the darknet containing budget, investment and strategy plans, as well as information about some Continental customers.
After Continental refused to pay a ransom, the hackers put the data up for sale for $50 million.
German prosecutors have been investigating the cyberattack since November 8, after Continental reported a cyberattack in August and revealed that some company data had been stolen.
About 40 terabytes of data were stolen in the attack.
The sources for this piece include an article in Reuters.