Nvidia has suffered its biggest one-day loss in market capitalization, paring over $280 billion in value, after the United States Department of Justice (DOJ) reportedly issued an antitrust subpoena.

Shares in Nvidia (NVIDIA) closed down 9.5% on Sept. 3 at $108, shaving $278 billion off its market cap. It’s the largest single-day value wipeout for any stock in the history of the US share market, per Google Finance data. 

Its shares continued to fall more than 2% to a low of $105 in after-hours trading.

Nvidia fell 9.5% on Sept. 3, closing the day at 8. Source: Google Finance. 

The sharp decline came as the DOJ sent a subpoena to Nvidia and several other companies as the government hunts for evidence that the chipmaking giant violated US antitrust laws, Bloomberg reported on Sept. 3, citing sources familiar with the investigation. 

The Justice Department had previously issued non-binding questionnaires to Nvidia to seek further information.

The subpoena marks an escalation in this process as the documents legally oblige recipients to hand over information and could mean the government is gearing up to issue a formal complaint against the chipmaker.

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Antitrust officials from the US government are worried that Nvidia is making it more difficult for businesses to switch to other AI and computer chip providers and has even penalized buyers that don’t exclusively use its own AI services, people familiar with the matter told Bloomberg. 

As part of its investigation into Nvidia DOJ officials have contacted other tech firms, including Nvidia’s largest investor Microsoft, for further information. 

“Nvidia wins on merit, as reflected in our benchmark results and value to customers, who can choose whatever solution is best for them,” the company said in an emailed statement to Bloomberg. 

Nvidia CEO Jensen Huang said he grants priority to customers who utilize Nvidia products in ready-to-go data centers, which he says is designed to prevent stockpiling and speed up the installation of his company’s tech. 

Founded in 1993, Nvidia has rapidly soared to become the world’s largest manufacturer of computer chips, specifically those used in AI processes. Nvidia’s success in facilitating AI-specific infrastructure has seen it massively outperform its rival chipmakers. 

At the time of publication, Nvidia’s $2.65 trillion market cap makes it 30 times larger than former market leader Intel and 12 times larger than rival Advanced Micro Devices (AMD). 

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