Just a year ago, Forbes listed Ross' net worth at $2.9 billion and included him in the Forbes 400 list of the richest Americans by net worth. The new report says Ross had just under $700 million in assets. It cited financial-disclosure forms filed by Ross after being nominated for his Commerce secretary.
After Forbes learned about this, the magazine said, it wanted to remove Ross from the Forbes 400. Ross protested, according to the report, telling the magazine it wasn't taking into account some trusts created for his family, which add "more than $2 billion" to his net worth and which he did not have to disclose in federal filings.
But the magazine said that after "one month of digging," it is confident that the more than $2 billion never existed. It said it removed him when it updated its list of richest Americans last month.
"It seems clear that Ross lied to us, the latest in an apparent sequence of fibs, exaggerations, omissions, fabrications and whoppers that have been going on with Forbes since 2004," Forbes' report said.
A Commerce Department spokesman told CNBC in a statement:
"Secretary Ross's disclosure documents were compiled by legal counsel and accountants. The relevant rules were followed, and the documents were closely reviewed and approved by ethics officials at the Department of Commerce and the Office of Government Ethics. We regret any earlier miscommunication."
Ross is listed on the "The World's Billionaires" list from March 2017 on Forbes' website. In it, he is No. 814, with a worth of $2.5 billion, just above private equity titan David Rubenstein. As of Tuesday, Forbes estimates Ross' net worth at $700 million.