How Chinese and Russian spies use ‘sex warfare’ to infiltrate Silicon Valley | Explained

“Sex warfare” involves the deliberate use of intimate, romantic, or sexual relationships to gain access to classified or commercially sensitive information, or to compromise individuals with such access. The method has its origins in Cold War intelligence operations but has become more complex in the modern technology landscape.

James Mulvenon, chief intelligence officer at Pamir Consulting and a 30-year veteran of counterintelligence investigations, told The Times that he has noticed a marked increase in these efforts. “I’m getting an enormous number of very sophisticated LinkedIn requests from the same type of attractive young Chinese woman,” he said. “It really seems to have ramped up recently.”

Mulvenon described an incident at a Virginia business conference focused on Chinese investment risks, where two attractive Chinese women attempted to attend despite not being invited. “It is a phenomenon. And I will tell you: it is weird,” he said.

He warned that such tactics are particularly effective against the United States. “It’s a real vulnerability,” Mulvenon explained, “because we, by statute and by culture, do not do that. So they have an asymmetric advantage when it comes to sex warfare.”

From affairs to family: The long game

One of the most concerning developments, officials say, is that modern “sex warfare” often takes the form of long-term operations that can last for years or even decades.

A former counterintelligence official told The Times of a case involving a “beautiful” Russian woman who married an American aerospace engineer working on defence-related projects. Before arriving in the United States, she had trained at a modelling academy and reportedly attended a “Russian soft-power school”. After disappearing for several years, she reappeared as a cryptocurrency specialist and became involved in the military-space innovation sector — all without her husband suspecting a thing.

Such operations are not brief encounters, officials say, but deliberate, multi-year efforts aimed at establishing trust, emotional dependence, and eventual access to classified or proprietary information.

The startup competition trap

Officials also warn that seduction is not the only tool used by foreign intelligence networks. Increasingly, Chinese-backed startup competitions are being identified as potential sources of risk. These events, often held in the United States, offer generous prizes and investment opportunities to young entrepreneurs. However, participation typically requires competitors to share their intellectual property, detailed business plans, and personal data.

One biotech chief executive who attended a global startup contest told The Times that he was closely monitored throughout. “They would record everything I would say, do and then ask questions like a reporter would,” he said. After winning a $50,000 prize, he was surprised when the organisers wired the funds directly to his personal account rather than the company’s. “That was weird,” he said.

Subsequently, the U.S. government froze his company’s federal funding, citing Asian investor ties disclosed during the pitch event. The decision effectively shut down his firm.

Mulvenon described the broader effect of such practices: “The percentage of foreign ownership crosses a threshold so the DoD can’t make any more investments in those companies, denying the government access to innovative startups and IP,” he said, calling it a tactic of “drafting”.

The cost of stolen secrets

The scale of economic damage caused by intellectual property theft is vast. The Commission on the Theft of American Intellectual Property estimates that U.S. losses reach as much as $600 billion annually, with China identified as the main source.

Some incidents are alarmingly direct. In July 2025, Chenguang Gong, a Chinese-American dual national from San Jose, California, pleaded guilty to stealing classified defence technology. According to the U.S. Department of Justice, Gong downloaded more than 3,600 files from a defence contractor, including blueprints for infrared sensors used to detect nuclear missile launches and devices designed to counter heat-seeking missiles.

Gong had previously applied to Chinese state-run “Talent Programmes” and wrote in a 2019 email that he had “taken a risk” because of his ties to the U.S. defence industry but hoped to contribute to China’s military chip-design capabilities. He faces up to ten years in prison.

Russia’s continued espionage tactics

While China is the dominant actor in technological espionage, Russia continues to deploy its own methods.

A 2018 Politico investigation revealed that Russian intelligence services had used Eastern European prostitutes in Silicon Valley nightclubs and luxury hotels to collect information from technology executives. One former FBI counterintelligence agent said, “If I were a Russian intelligence officer, and I knew that these high-end girls were dragging CEOs of major companies back to their rooms, I’d be paying them for info too.”

According to another official, “You don’t need to be on the inside, you just need somebody on the inside that you have access to.”

Espionage beyond traditional spying

What distinguishes the current threat, officials say, is that many of the individuals involved are not conventional spies. As one senior counterintelligence official told The Times, “We’re not chasing a KGB agent in a smoky guesthouse in Germany anymore.”

Instead, “our adversaries, particularly the Chinese, are using a whole-of-society approach to exploit all aspects of our technology and Western talent.” This means recruiting businesspeople, academics, crypto analysts, and students rather than formally trained intelligence officers.

In the Bay Area, officials have estimated that roughly 20 per cent of all FBI counterintelligence cases involving intellectual property originate there. Chinese operatives are known to pressure U.S.-based Chinese nationals into cooperation by threatening their relatives in China.

San Francisco: A hub of interest

The San Francisco Bay Area, encompassing Silicon Valley, major universities, and global technology firms, has long attracted foreign espionage. Its open, innovative culture makes it particularly susceptible to subtle influence and infiltration.

According to officials, China’s Ministry of State Security has maintained a unit focused specifically on California and has conducted operations through political intermediaries, student organisations, and diaspora networks.

One notable case involved a staff member in Senator Dianne Feinstein’s San Francisco office, who allegedly reported on local political matters to Chinese intelligence for years. During the 2008 Beijing Olympics torch relay — the only U.S. stop being San Francisco — Chinese officials were observed directing busloads of students to drown out protests by Tibetans, Falun Gong practitioners, and pro-democracy activists.

Former FBI officials say many Silicon Valley firms still underreport espionage incidents, fearing reputational harm and investor concern. With the region positioned at the centre of global innovation, its vulnerabilities remain deeply embedded.

A growing and personal threat

Jeff Stoff, a former national security analyst, told The Times, “China is targeting our startups, our academic institutions, our innovators, our DoD-funded research projects. But there’s not enough oversight and action. It’s all intertwined as part of China’s economic warfare strategy, and we’ve not even entered the battlefield.”

That battlefield now extends far beyond data breaches and cyber intrusions. It includes dating apps, conferences, personal inboxes, and social interactions. As Mulvenon warned, “It’s the Wild West out there.”