US Commerce Secretary Wilbur Ross held assets for much of last year that created conflicts of interest and has since transferred ownership to a family trust instead of divesting outright.
Days before coming under negative media scrutiny last year, Ross shorted stocks in a company tied to Russian President Vladimir Putin's inner circle in a way that would have let the commerce chief benefit from falling share prices, according to the magazine.
The Commerce Department told AFP that, along with the US Office of Government Ethics, it had certified that the transactions at issue were in compliance with legal requirements.
"The secretary continues to follow the guidance of Department of Commerce ethics officials to ensure compliance with federal laws and regulations," the agency said in a statement.
Citing previously undisclosed reports Ross filed with the ethics office, the magazine said Ross had sold some assets to the investment bank Goldman Sachs.
But he moved others to a family trust, leaving his family's wealth tied to China, Russia and others he dealt with as commerce secretary, according to the report.
These assets included a stake in a shipping company and an auto parts company, both of which stood to be directly affected by Washington's escalating trade dispute and both of which are co-owned by the Chinese government, according to Forbes.
In October and November, as journalists working on the Panama Papers revelations were preparing to expose Ross's stake in Navigator Holdings, a shipping firm whose owners include Putin's son-in-law, Ross sold his shares in the company, according to Forbes.
He then opened a short position in the company, meaning that if its share price went down, he would profit, the magazine said.
In November, the magazine removed Ross from its billionaires list, saying he had inflated his personal fortune for more than a decade.