(Reuters) — The U.S. Department of Justice is investigating chip giant Nvidia's (NVDA) buyout of AI startup Run:ai on antitrust grounds, Politico reported on Thursday, citing five people with direct knowledge of the matter.

Nvidia shares fell over 3% in premarket trading on Friday, after ending Thursday's session 6.7% lower.

Nvidia announced the acquisition of the Israeli firm in April for around $700 million, according to a report by TechCrunch.

Run:ai's technology allows developers and teams to manage and optimize their artificial intelligence infrastructure.

"We'll continue to support aspiring innovators in every industry and market and are happy to provide any information regulators need," an Nvidia spokesperson said.

The Justice Department did not immediately respond to a Reuters request for comment.

U.S. antitrust enforcers have been closely examining Big Tech acquisition activity due to concerns that the concentration of new technologies in the hands of a few companies could stifle competition.

Reuters reported last month that the French antitrust regulator was set to charge Nvidia for alleged anti-competitive practices.

Nvidia's profits and revenues have soared over the past year as its processors become the gold standard in the chip industry due to their ability to power AI applications, including training models like ChatGPT.

(Reporting by Zaheer Kachwala in Bengaluru; Editing by Tasim Zahid)