New York, New York - A key selling point of Donald Trump's 2016 presidential run was that he was a businessman, not a politician, but his corporate empire is now in jeopardy.

Earlier this week, Judge Arthur Engoron ruled that the former president, his sons, and the Trump Organization had engaged in "persistent and repeated fraud."

The ruling stemmed from a fraud case brought by New York Attorney General Letitia James, which will go to trial before a jury next Monday.

In a partial victory for James, Judge Engoron found there had been a systemic overvaluation of assets, such as Trump Tower and other properties, to better negotiate with banks.

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In addition to finding that Trump and his sons committed fraud, the judge also revoked their state business licenses and asked the parties to propose receivers to manage the dissolution of the companies in question.

James is seeking $250 million in penalties and the removal of Trump and his sons from management of the family empire, the Trump Organization.

Engoron's initial decision puts in jeopardy Trump's control over not just the iconic Trump Tower, but other restaurants and boutiques, as well as high-end commercial property.

While it is not clear whether Trump will have to sell his assets affected by the ruling, or if they could be overseen by a yet-to-be-named receiver, the ruling is damaging for the Republican billionaire.

"Trump's ability to do business in New York State has pretty much ended by this ruling," Pace University law professor Bennett Gershman told AFP. "The overseer can now manage the properties. Basically, Trump and his organization will not be allowed to manage these properties anymore."

The ex-president's lawyers immediately announced their appeal, with Trump's camp accusing Engoron of trying to "nationalize one of the most successful corporate empires in the United States and seize control of private property."

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For Trump, who is seeking the White House again in 2024, the stakes are high: according to Forbes magazine, the 77-year-old's New York real estate represented $720 million of his $2.5 billion fortune.

The ruling serves as a symbolic blow to "the story that Donald Trump tells about himself as a businessman," says Will Thomas, a University of Michigan assistant professor of business law.

"We've seen even before he was president, Donald Trump really cares about his net worth as a reflection of his talent," Thomas told AFP. "And what we saw yesterday is a court saying, 'There's no dispute about the fact that Donald Trump has systematically lied about his wealth,' in really dramatic ways, up to hundreds of millions or even billions of dollars."

But if Trump's business dealings were key to helping him win the White House once before, it's unclear if the potential dissolution of his empire will hurt him this time around.