The FBI was brought on board by the German security authorities, the person said, confirming an earlier report in the German newspaper Handelsblatt.
Continental declined to comment on Wednesday, and the FBI was not immediately available for comment.
Continental said earlier this month that it was investigating the theft of company data in a cyberattack in August but declined to comment on media reports that hackers had put the information up for sale.
Handelsblatt had reported at the time that hackers had published a list of the data on the darknet and that it included budget, investment and strategy plans, as well as information related to some Continental customers.
Handelsblatt said the hackers had put the data up for sale for $50 million after Continental "apparently did not want to pay a ransom."
Continental, based in Hanover, Germany, ranks No. 8 on the Automotive News Europe list of top 100 global suppliers, with 2021 sales to automakers of $22.4 billion.