Prosecutors said Saturday they are seeking to freeze up to 1.5 billion reais ($635 million) in assets of Eike Batista, once considered Brazil's richest man, accusing him of market manipulation and insider trading.
The tycoon's financial assets, houses, apartments, cars, ships and planes, as well as assets placed in his wife and children's names after the alleged crimes occurred, would be affected, the Rio de Janeiro prosecutor's office said.
"The entrepreneur is accused of market manipulation and undue use of privileged information," a statement said.
Prosecutors Rodrigo Ramos Poerson and Orlando Monteiro da Cunha said a court will decide whether to try Batista, who faces up to 13 years in prison if convicted.
Batista denied the allegations under questioning by police, his lawyers Raphael Mattos and Ary Bergher told the G1 news site.
"This effectively has not the least basis in evidence," Mattos was quoted as saying.
Batista was considered Brazil's richest man with a fortune estimated at $30 billion in 2012, before his mining and energy empire began to unravel.
His OGX oil company sought bankruptcy protection in October 2013 after admitting it could not meet its production goals.
The crisis affected other companies in his EBX Group conglomerate and by late last year his net worth was valued at less than $100 million.