Trump Administration Export Controls on Anthropic AI Stem From Dispute Over SK Telecom Access, Sources Say

According to people briefed on the situation, the Trump administration’s decision to impose export controls on Anthropic’s most powerful artificial intelligence technology followed a conflict over the company granting South Korean telecom giant SK Telecom access to its Claude Mythos model. US officials raised concerns over alleged unaddressed ties between SK Telecom and China, the sources confirmed.

Those initial concerns intensified after Amazon later notified the White House of vulnerabilities its researchers identified in Fable 5, a heavily safeguarded public version of Mythos that Anthropic launched on June 9. Amazon’s research team claimed bad actors could bypass some of Fable 5’s built-in safety guardrails to access Mythos’ advanced cyber capabilities, though Anthropic and independent cybersecurity experts have pushed back, noting these risks are not unique to Claude models.

The combination of these two events ultimately led the White House to conclude it could not trust Anthropic to secure its most cutting-edge AI technology, according to a source close to the Trump administration. Last Friday, officials ordered Anthropic to revoke access to Mythos and Fable 5 for all foreign nationals, including immigrants currently residing in the United States.

Rather than building a nationality-based access gatekeeping system—a process that would be logistically difficult to implement while protecting user privacy—Anthropic opted to disable access to both models entirely. After days of negotiations over restoring access to Claude Mythos and Fable 5, the White House and Anthropic remain at an impasse.

Claude Mythos is uniquely skilled at detecting software vulnerabilities, so Anthropic restricted early access to a small group of vetted trusted organizations through its invite-only initiative called Project Glasswing. Earlier this month, Anthropic expanded the program “following several weeks of close collaboration” with outside experts and the US government, and SK Telecom (South Korea’s largest wireless carrier) became one of roughly 150 companies granted access to Mythos.

Anthropic declined to comment on the record. The White House and SK Telecom did not immediately respond to requests for comment. The Washington Post previously reported that Trump administration officials were alarmed to learn Mythos’ access list included a “South Korean telecommunications company” they suspected of Chinese links, though the outlet did not name the firm. In response to that reporting, SK Telecom told a South Korean newspaper that “the anonymous insider’s remarks in foreign media lack verified facts, and our company has no ties to China.”

A source close to Anthropic said the company views SK Telecom’s access to Mythos and the vulnerabilities Amazon identified as separate, unrelated issues. They noted that the formal letter the US government sent to Anthropic, demanding access to Claude Mythos and Fable 5 be restricted solely to US nationals, makes no mention of the South Korean company or China.

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According to a source close to the AI lab, shortly after Anthropic announced Project Glasswing’s latest expansion earlier this month, the White House asked Anthropic to revoke SK Telecom’s access to Mythos. Sources tell WIRED that Anthropic complied with the request immediately, and the US government did not threaten to impose broad export controls on the model at that time.

SK Telecom has invested in Anthropic multiple times, including a $100 million investment in 2023 that coincided with the launch of a commercial partnership to build a custom AI model tailored to the telecommunications industry. It was one of multiple South Korean organizations participating in Project Glasswing, alongside Samsung Electronics and the Korea Internet and Security Agency.

While SK Telecom itself does not maintain large-scale operations in China, it is part of the massive SK Group conglomerate, whose affiliates hold extensive business interests across China spanning semiconductors, energy, and other core industries.

Per SK Telecom’s 2024 annual report, the firm generated only around $1.9 million in revenue from China last year, almost all from investment-related activities, and employed just seven people across its Chinese operations.

But the company’s presence in China’s telecom sector stretches back more than 20 years. In 2004, SK Telecom and state-owned Chinese carrier China Unicom launched a joint venture called UNISK to provide wireless internet and mobile content services across China. It was one of the first joint ventures between a foreign firm and a Chinese state-owned carrier.

In 2006, SK Telecom invested $1 billion in convertible bonds issued by China Unicom’s Hong Kong-listed unit, which were later converted to an approximately 6.6 percent equity stake. The partnership began unwinding several years later: SK Telecom sold its stake in China Unicom back to the Chinese carrier in 2009 for roughly $1.3 billion, though it has retained a small financial stake connected to the original UNISK venture. In its 2025 filing with the US Securities and Exchange Commission, SK Telecom listed its UNISK investment at a value of roughly $17 million.

In 2021, the first Trump administration restricted US investment in China Unicom as part of a broader campaign targeting Chinese firms Washington says are tied to China’s military and intelligence sectors. This past April, citing national security concerns, the US Federal Communications Commission proposed barring US telecom firms from interconnecting their networks with China Unicom and other Chinese carriers. China Unicom has recently warned that the proposed ban could disrupt global communications.

Hugo Lowell and Zeyi Yang contributed reporting to this article.