In a dramatic shift in the AI industry landscape, Anthropic has surpassed OpenAI in secondary market valuation, now trading at an implied $1 trillion on platforms like Forge Global. This marks a significant milestone, as rival OpenAI trades at approximately $880 billion on the same platform, according to Forge CEO Kelly Rodriques. Just three months ago, Anthropic's valuation was $380 billion following a $30 billion Series G round led by GIC and Coatue, meaning secondary markets are now pricing the company at nearly three times that figure.
The staggering valuation surge is fueled by Anthropic's explosive revenue growth, with annualized run rates jumping from $9 billion at the end of 2025 to $30 billion by March 2026—a 233% increase in a single quarter. This growth is driven primarily by enterprise adoption of its Claude Code and API products, along with Amazon's commitment of up to $25 billion in additional investment. Caplight, which tracks private-market share activity, reported that interest in Anthropic has spiked over 650% in the last 12 months.
Meanwhile, OpenAI's secondary market performance appears stagnant, trading just 3% above its early-2026 fundraising round valuation of $852 billion. Caplight found that in Q1, OpenAI reported more people interested in selling than buying its shares on secondary markets. Despite this, OpenAI CEO Sam Altman has been vocal about his concerns regarding Anthropic's marketing strategies for its powerful new AI model, Claude Mythos.
Claude Mythos and the Safety Debate
Speaking on the Core Memory podcast hosted by tech journalist Ashlee Vance, Altman accused Anthropic of using “fear-based marketing” to promote Claude Mythos, a model with unprecedented ability to autonomously identify software vulnerabilities and execute complex cyber operations. Altman argued that such tactics are designed to keep AI in the hands of a “smaller group of people.”
“If what you want is like 'we need control of AI, just us, because we’re the trustworthy people', I think fear-based marketing is probably the most effective way to justify that,” Altman said. He compared Anthropic's approach to selling a bomb shelter: “'We have built a bomb. We are about to drop it on your head. We will sell you a bomb shelter for $100 million.'”
Claude Mythos, revealed last month, has drawn intense attention from researchers, governments, and the cybersecurity industry. Testing has shown it can autonomously identify hundreds of vulnerabilities in major software like Mozilla’s Firefox browser and carry out multi-stage cyberattack simulations. Anthropic has restricted access via Project Glasswing, granting select companies including Amazon, Apple, and Microsoft the ability to test the system. The UK’s AI Security Institute found the model could autonomously complete complex cyber operations, while the U.S. National Security Agency has reportedly begun testing a preview version on classified networks.
Despite concerns, a group of researchers claimed they were able to reproduce Mythos' findings using publicly available models. On prediction market Myriad, users put a 49% chance on Claude Mythos being released to the wider public by June 30.
Altman acknowledged that while there are legitimate safety concerns, not all alarmist rhetoric should be taken at face value. “There will be a lot more rhetoric about models that are too dangerous to release. There will also be very dangerous models that will have to be released in different ways,” he said, while affirming that OpenAI has a plan for responsibly deploying such capabilities.
Reports suggest Anthropic is exploring a public debut as early as late 2026, with Goldman Sachs and JPMorgan advising, targeting an IPO valuation in the $400–$500 billion range. IPO groundwork has been underway since at least late 2025.
