Cyberattacks aimed at stealing American artificial intelligence technology are increasingly expanding from tech-based attacks to the exploitation of human-level vulnerabilities, with China-based actors playing a growing role. "As the AI race has heated up, the [People's Republic of China] has targeted the tech sector increasingly," said Matt Pearl, director of the strategic technologies program at the U.S.-based think tank Center for Strategic and International Studies. Rather than focusing on a specific trade secret, such as hardware designs, the hackers have broadened their interest to anything that could narrow the three- to four-month AI gap with the U.S., Pearl said.

That, he said, ranges from understanding a company's product roadmap, particularly in highly competitive sectors, to identifying weaknesses in supply chains. The alleged cases are already piling up. In June, U.S.-based cybersecurity giant CrowdStrike said Chinese entities accounted for more than half of state-sponsored intrusions targeting technology companies, especially their AI assets, in the 12 months through March 31.

American tech start-up Anthropic has also accused Chinese companies, including Alibaba, of illicit attempts to steal its AI capabilities. Alibaba did not respond to a request for comment. Last year, U.S.-based AI content detection startup Copyleaks said the responses generated by Chinese startup DeepSeek's R1 model resembled those produced by OpenAI's ChatGPT nearly three-quarters of the time, suggesting the open-source Chinese model may have been trained on the U.S.-developed one.

"We haven't seen [the same stylistic match] in other LLMs," said Alon Yamin, CEO and co-founder of Copyleaks. DeepSeek and OpenAI did not immediately respond to requests for comment. Brian Abbott, founder and CEO of U.S.-based start-up Agentiq Capital, told CNBC in June that he believed an employee he hired from China last year was an agent of Beijing who purposely altered code and website content to prevent the company from getting venture capital funding.

Abbott alleged the employee replaced references to "ASI," or artificial superintelligence, with "fintech," a once-trending term that many investors have soured on. The individual was dismissed earlier this year, Abbott said, and the company filed a complaint with the FBI. CNBC was unable to independently verify the allegation.

"China's economic espionage campaign is a continuing threat that costs the American economy hundreds of billions of dollars per year and puts our national security at risk," the FBI said in a statement to CNBC. "The FBI prioritizes investigating any potential theft of US technology by foreign actors and remains unwavering in our commitment to protect the homeland." The Cyberspace Administration of China and the U.S. Department of State did not offer a comment when contacted by CNBC.

None of the individuals interviewed for this piece said they had heard of a similar instance of state-directed subversion of U.S. technology. Graham Webster, editor-in-chief of Stanford University's DigiChina Project, said distinguishing state-sponsored espionage from individual or corporate-level efforts can be difficult.