Shareholders sued chipmaker Nvidia and its chief executive, Jensen Huang, on Monday, accusing them of concealing his alleged relationship with a suspected Chinese intelligence asset.

The proposed class action adds to investigations into whether Huang was targeted by foreign intelligence, raising questions about the security of sensitive information at the world's most valuable chipmaker.

What does the lawsuit allege?

The complaint, filed in federal court in San Jose, California, alleges that Nvidia and Huang misled investors about his relationship with Alice H., a former executive at Singapore-based Megaspeed.

Shareholders say the defendants failed to disclose national security concerns that threatened Nvidia's reputation and business prospects. They are seeking unspecified damages.

The New York Times reported last month on the alleged relationship and said US authorities had concluded that Alice H. was a Chinese intelligence asset.

What have Nvidia and Huang said?

Nvidia announced an independent investigation Sunday into reports that Huang had been the "target of a foreign intelligence effort."

Huang acknowledged being unfaithful to his wife in an open letter, but did not identify the woman.

"I support the investigation and will cooperate fully," he said. "I am committed to protecting NVIDIA and supporting America's national security."

Nvidia shares closed down 4.3% Monday. The lawsuit was filed five minutes after US markets closed.

How have Washington and Beijing responded?

US President Donald Trump said Monday that the FBI was investigating the matter, while expressing support for Huang.

Trump said he had spoken to the executive earlier that day.

"He said he had absolutely no idea that the person in question was a spy," Trump told reporters.

China denied conducting an intelligence operation targeting Huang.

"The so-called Chinese spy allegation is unsubstantiated. It is nothing but smears against China," Foreign Ministry spokesperson Guo Jiakun said.

Why does the case matter for the AI industry?

Huang co-founded Nvidia and led its transformation from a maker of gaming chips into a leading supplier of the computing technology powering artificial intelligence.

Its advanced chips have become a focus of US-China competition, with Washington restricting exports to limit Beijing's access to the technology.

Huang has pushed for looser restrictions on sales to China. The investigations have intensified scrutiny of his leadership and whether confidential company information was compromised.