What Happened to SK Telecom and Anthropic's Mythos Controversy?
The "SK Telecom and Anthropic's Mythos Controversy" refers to the June 2026 US government directive that led Anthropic to disable its advanced AI models, Mythos 5 and Fable 5, globally. This action was primarily triggered by national security concerns over South Korean telecom giant SK Telecom's access to Mythos, due to alleged ties to China, compounded by reported vulnerabilities in Fable 5. As of June 19, 2026, the models remain offline, though Anthropic is optimistic about their restoration.
Quick Answer
In June 2026, the US government ordered Anthropic to suspend access to its powerful AI models, Mythos 5 and Fable 5, for all foreign nationals, citing national security concerns. This directive was prompted by South Korean telecom SK Telecom's access to Mythos through Project Glasswing and alleged connections between SK Telecom and China, alongside reports of a "jailbreak" in Fable 5. Anthropic complied by taking both models offline globally. While SK Telecom denies China ties and has recently made another investment in Anthropic, the models remain inaccessible as of June 19, 2026, though Anthropic anticipates their swift return.
📊Key Facts
📅Complete Timeline13 events
Anthropic Founded
Anthropic, an American artificial intelligence company focused on AI safety and developer of the Claude LLM series, was founded by former members of OpenAI.
SK Telecom's Initial Investment in Anthropic
SK Telecom made an initial investment of US$100 million in Anthropic, acquiring approximately a 0.3% stake in the AI company.
Project Glasswing Launch
Anthropic launched Project Glasswing, a controlled initiative to provide early access to its high-risk Claude Mythos model to a limited number of organizations, primarily in the US, for cybersecurity defense.
Anthropic Series G Funding Round
Anthropic raised $30 billion in a Series G funding round, bringing its post-money valuation to $380 billion.
SK Telecom Unveils 'AI Native' Strategy
SK Telecom CEO Jung Jai-hun announced the company's 'AI Native' innovation strategy at MWC 2026, outlining major investments in AI infrastructure, data centers, and the development of its own large language models.
Anthropic Series H Funding Round
Anthropic raised $65 billion in Series H funding, led by Altimeter Capital, Dragoneer, Greenoaks, and Sequoia Capital, valuing the company at $965 billion post-money.
Anthropic Files Confidential IPO Papers
Anthropic announced it had filed confidential initial public offering (IPO) papers with the United States Securities and Exchange Commission, targeting a debut in the fall of 2026.
Project Glasswing Expansion
Anthropic expanded Project Glasswing to approximately 150 new organizations across more than 15 countries, including SK Telecom, to test Mythos for cybersecurity defense.
Anthropic Releases Fable 5
Anthropic launched Fable 5, a public version of its Mythos-level AI model, designed with safety features for general use.
US Government Orders AI Model Suspension
The US government issued an export control directive to Anthropic, ordering the suspension of access to Mythos 5 and Fable 5 for all foreign nationals, citing national security concerns and reported 'jailbreaks' in Fable 5. Anthropic complied by disabling both models globally.
Anthropic Opens Seoul Office
Anthropic opened a Seoul office and signed a memorandum of understanding with South Korea's Ministry of Science and ICT, naming SK Telecom among its local partners.
SK Telecom Identified as Controversy's Center
Wired identified SK Telecom as the South Korean carrier at the center of the Mythos controversy, detailing alleged ties to China that alarmed US officials. SK Telecom denied these allegations to a Korean newspaper.
Models Remain Offline, Anthropic Optimistic
As of today, Mythos 5 and Fable 5 remain offline. However, Anthropic's Managing Director of International, Chris Ciauri, expressed confidence that the models would be restored "in the coming days." SK Telecom also announced an additional investment in Anthropic, emphasizing continued collaboration.
🔍Deep Dive Analysis
The controversy erupted in June 2026 when the US government, under the Trump administration, issued an export control directive to Anthropic, demanding the suspension of access to its cutting-edge AI models, Mythos 5 and Fable 5, for all foreign nationals. This unprecedented intervention in commercially deployed AI led Anthropic to take both models entirely offline globally to ensure compliance, rather than attempting to implement complex nationality-based restrictions.
The core of the controversy stemmed from two main factors. Firstly, US officials expressed significant concern over South Korean telecom giant SK Telecom's access to Anthropic's highly capable Mythos 5 model through its Project Glasswing initiative. These concerns were rooted in alleged historical and ongoing ties between SK Telecom and China, including a past joint venture with state-owned China Unicom and the broader SK Group's extensive business interests in China. SK Telecom, an early investor in Anthropic with a $100 million investment in 2023, denied these allegations, stating a lack of verified facts and no ties to China. Secondly, the situation was exacerbated by reports from Amazon researchers who identified methods to "jailbreak" or bypass the safety safeguards in Fable 5, a publicly released version of Mythos. This raised fears that Fable 5 could be weaponized for cyberattacks, further eroding the White House's confidence in Anthropic's ability to secure its advanced technology.
The initial turning point was Anthropic's expansion of Project Glasswing in early June 2026, which included SK Telecom among approximately 150 new organizations granted access to Mythos 5. Shortly after, the White House directly ordered Anthropic to revoke SK Telecom's access, a demand Anthropic immediately met. Days later, the combination of the SK Telecom dispute and the Fable 5 vulnerabilities prompted the broader export control directive, forcing the global shutdown of Mythos 5 and Fable 5 on June 12, 2026.
The immediate consequence was the global unavailability of Anthropic's most advanced AI models, Mythos 5 and Fable 5, impacting hundreds of millions of users and partners. This action set a significant precedent for government intervention in the AI industry and sparked a debate among cybersecurity experts, with some criticizing the ban for potentially hindering cyber defense capabilities and US AI leadership. The controversy also highlighted the escalating geopolitical tensions surrounding advanced AI technology and national security.
As of June 19, 2026, Mythos 5 and Fable 5 remain offline. However, Anthropic's Managing Director of International, Chris Ciauri, expressed confidence during a press conference in Seoul that the models would be restored "in the coming days." Despite the controversy, SK Telecom reaffirmed its commitment to Anthropic, making an additional undisclosed investment in June 2026, emphasizing a continued cooperative relationship beyond IPO profits. Anthropic itself has seen substantial growth and funding, with a Series H funding round in May 2026 valuing the company at $965 billion, and it confidentially filed for an IPO in June 2026. SK Telecom continues to pursue its "AI Native" strategy, investing heavily in AI infrastructure and aiming to be a global AI leader.
What If...?
Explore alternate histories. What if SK Telecom and Anthropic's Mythos Controversy made different choices?