Mario Theissen has played down the negative speculation that is circulating about the BMW-Sauber team's new owner Qadbak.
The group has raised eyebrows in the F1 paddock because the identities of its owners have not been revealed.
Rumours have circulated that one of those involved with Qadbak has spent time in jail for financial-related crimes.
Qadbak has also bought the English football club Notts County, and the governing body Football League has been investigating the transaction before approving it.
The club on Sunday released a statement confirming that the Middle Eastern based Shafi and Hyat families are involved with Qadbak.
A Notts County spokesman said: "The confusion and misplaced allegations of the last few days have forced us to ask them to reveal themselves."
Leading BMW-Sauber figures Theissen and Peter Sauber have also told the media in recent days that Qadbak had asked for the identities of the investors to remain undisclosed.
Theissen is quoted as saying by Germany's Sport Bild: "The new owner is a very strong company and is strong enough to operate a Formula One team.
"We do not have any reason to question their seriousness," he added in Singapore.