The White House’s reported deals with chipmakers Nvidia (NVDA) and Advanced Micro Devices (AMD) for a cut of their chip sales to China are unorthodox and unprecedented — and likely to end up in court.

The two pacts, according to multiple reports, would divert 15% of the companies’ respective sales revenues earned on China-destined chips to the US government. In exchange for the profit sharing, the US would grant export licenses allowing Nvidia to resume sales of its H20 chips to China and AMD to resume sales of its MI308 chips to China.

Wall Street is happy, at least in early afternoon trading on Monday: Both Nvidia and AMD stocks are up.

But legal experts say that neither the president nor Congress is empowered to tax exports. Article I, Section 9, of the US Constitution, known as the Export Clause, prohibits such levies, saying, "No Tax or Duty shall be laid on Articles exported from any State.”

“The Constitution is clear that there really cannot be any tax on exports,” said Douglas Jacobson, an international trade lawyer with Jacobson Burton Kelley. “In my view, it's a slam-dunk unconstitutional tax on exports.”

And the US Supreme Court has interpreted the Export Clause to prohibit Congress from imposing duties on exports, even when they’re characterized otherwise.

Its controlling view on federally mandated export charges was stated in the unanimous 1998 decision in United States v. United States Shoe Corp.

In that case, the high court struck down a congressionally approved ad valorem charge of 0.125% on exports imposed by the US Customs Service. The charge, calculated based on the value of commercial cargo shipped through US ports, known as the Harbor Maintenance Tax (HMT), was intended to fund upkeep on US harbors.

On behalf of former President Bill Clinton’s administration, the US Solicitor General argued that the HMT was a “user fee,” and not a tax. But the court disagreed, reasoning that because the charge operated like an export tax, it violated the Export Clause.

Siding with US Shoe, the court said in its opinion that the HMT “bears the indicia of a tax.”

Beyond the Constitution’s export tax prohibition, the Export Controls Reform Act, passed by Congress in 2018, specifically prohibits charging exporters to obtain export licenses.

Under US law, certain fees on export licenses have been held constitutional.

Military exports, for example, are treated differently from non-military goods and fall under the administration of the US State Department, which requires manufacturers of military items to pay annual licensing fees. Even so, those fees are not based on the value of an applicant’s exports.

“User fees are entirely permissible,” Jacobson said, but a deal for chipmakers to pay the government a 15% profit share acts like a reverse tariff and “is clearly not a user fee.”

"None of us have seen the government get a piece of the pie in this explicit way before," Tom Essaye, Sevens Report Research founder, told Yahoo Finance on Monday.

A spokesperson for Nvidia neither confirmed nor acknowledged the reported profit-sharing agreement.

“We follow rules the US government sets for our participation in worldwide markets. While we haven't shipped H20 to China for months, we hope export control rules will let America compete in China and worldwide,” the spokesperson said. “America cannot repeat 5G and lose telecommunication leadership. America’s AI tech stack can be the world’s standard if we race."

Exactly who might legally challenge revenue sharing plans is not altogether clear. Nvidia and AMD are unlikely to dispute their own accords. And so far, challenges from rival chipmakers are unlikely, as there’s no indication that other exporters would be subject to similar agreements.

Potential challenges, however, could come from Nvidia and AMD shareholders and possibly from state attorneys general.

Jacobson, the trade lawyer, said it's possible shareholders could argue that the profit-sharing agreements create an adverse effect on the price of the companies' shares because the businesses are subject to an unconstitutional tax that decreases their revenue.

State attorneys general, on the other hand, may be able to argue that the deal impacts a company operating within their state or jeopardizes the state’s revenue.

For Nvidia and AMD, the agreements make sense as a short-term play, Jacobson said, even though they would likely be invalidated if challenged.

By signing on to the agreements, the companies may be able to get their chips flowing to China and later deal with clawing back damages they may be entitled to.

In an interview with Yahoo Finance, Pangaea Policy founder Terry Haines said the agreements may turn out to be a "one-off" for the administration due to concerns that the strategy could spread beyond Nvidia and AMD and because of China's concerns that US chips could contain "backdoors" that allow for US tracking.

"The Chinese are saying they may not want the chips after all," Haines said.

Alexis Keenan is a legal reporter for Yahoo Finance. Follow Alexis on X @alexiskweed.

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