Swiss jeweller and watchmaker De Grisogono has filed for bankruptcy.
The company is majority-owned by Sodiam, Angola’s state diamond firm, and Sindika Dokolo, husband of Isabel Dos Santos, reportedly Africa’s richest woman.
Ms Dos Santos, who lives mainly in London, is under investigation in Angola for enriching herself through corruption during the time her father was president of the country.
The BBC reports prosecutors are now seeking to recover $1bn (£760m) which they claim the 46-year-old billionaire and her associates allegedly owe the state.
They deny all allegations.
BBC’s Panorama investigative reporting team and other news outlets say that Sodiam and Mr Dokolo became 50-50 owners of De Grisogono in 2012.
Leaked documents seen by the Panorama team show that 18 months after the deal, Sodiam had put $79m into the partnership, while Mr Dokolo had only invested $4m. Sodiam also awarded him a €5m success fee, meaning he was effectively paid $1m for acquiring half the business.
Mr Dokolo’s lawyers say he later invested $115m in De Grisogono as it ran into financial difficulties and could not find a buyer for the business.
The privately-held company is thought to have sales of around $100 million per year. It filed for bankruptcy in Switzerland where it employs around 65 people.
