Cloud computing giant Oracle’s revenue fell short of Wall Street expectations, sending its shares plummeting more than 10% in after-hours trading on Wednesday.

The company reported revenue of $16.06 billion (£11.99 billion) for the three months to November, compared with analysts’ expectations of $16.21 billion.

The company said revenue from its artificial intelligence business, Oracle Cloud Infrastructure (OCI), rose 14% and sales increased 68%.

OCI serves major developers of artificial intelligence technology, and their demand for Oracle’s artificial intelligence infrastructure helped the company’s stock hit new highs this fall, but Wednesday’s results failed to calm concerns about a potential artificial intelligence bubble.

In September, Oracle struck a highly sought-after contract with ChatGPT maker OpenAI, which agreed to buy $300 billion in computing power from Oracle over five years.

After the news was announced, Oracle Chairman and Chief Technology Officer Larry Ellison briefly became the world’s richest man.

But the company’s shares have fallen 40% since their peak three months ago. Still, they are up more than a third since the start of the year.

In a statement on Wednesday, Mr. Ellison struck a cautious tone.

“There will be a lot of changes in AI technology over the next few years, and we must remain agile to respond to these changes,” he wrote.

Ellison also appeared to snub Nvidia, a designer of highly complex artificial intelligence chips, saying Oracle would buy chips from any manufacturer in order to serve its customers.

In a policy he calls “chip neutrality,” Ellison declared: “We will continue to buy the latest GPUs from Nvidia, but we need to be ready and able to deploy any chip that customers want to buy.”

Oracle is involved in a number of AI infrastructure arrangements that increase the likelihood that major players in the industry will engage in “revolving financing” transactions, in which companies fund the purchase of their own products and services.

“Oracle’s earnings come as investors weigh whether its massive OpenAI partnership means overexposure to a customer currently in the spotlight over profitability concerns,” Emarketer analyst Jacob Bourne said after the company’s quarterly report.

Byrne said Oracle is facing increasing scrutiny as it accumulates debt to build data centers.

Oracle raised a record $18 billion in a massive bond sale in September, one of the largest ever in the technology industry.

“While Oracle’s stock price has been boosted by a surge in September, the decline in revenue is likely to exacerbate already cautious investors’ concerns about its OpenAI deal and its aggressive artificial intelligence spending,” Byrne said.

The Ellison family, supporters of U.S. President Donald Trump, also recently acquired Paramount and spearheaded the acquisition of Warner Bros. Discovery, another major Hollywood studio.