South Korean prosecutors have recommended that Hyundai Motor Company's chairman Chung Mong-koo spend six years in prison for embezzlement.
Hyundai has faced worker unrest
Mr Chung has been on trial since June 2006 for raising money illegally from subsidiaries and spending some 69.3bn won ($74m) for his own use.
He was also charged with damaging related firms financially via dubious deals, to his and his sons' benefit.
The news comes amid falling profits and a partial strike at the firm.
Hyundai - the country's largest car firm, and its affiliate Kia Motors, which is headed by Eui-sun, Mr Chung's son - represent some 70% of South Korea's automobile exports.
Following their call, prosecutors said it was "unavoidable to seriously punish the defendants" because the crimes in the case were "grave".
It is now up to judges in Seoul to rule on the case, which local media said could take place in February.
The latest news comes as Hyundai faces increasing difficulties with poor results, dented in part by the strength of the South Korean won, making it harder to export vehicles.
A strike on Monday, which lasted eight hours at three factories following a row with management over bonuses, come after the firm experienced a more protracted three-month strike last summer.
A longer strike could start from Wednesday.