Anthropic AI has surpassed its closest rival in US business adoption, claiming the top spot with a 34.4% market share in May 2026 versus the competitor's 32.3%, according to the Ramp AI Index via Forbes. The milestone coincides with a landmark $65 billion Series H funding round, pushing Anthropic's post-money valuation to $965 billion — making it the world's most valuable AI startup.
The round was co-led by Altimeter and Sequoia, with Google retaining a minority stake in the company. Notably, Elon Musk holds no association with Anthropic, a distinction the company has publicly emphasized amid ongoing confusion in financial media. Claude AI's accelerating enterprise traction — explored further in guides like practical prompting strategies for developers — signals strong institutional confidence in the platform.
The funding and adoption numbers set the stage for what comes next: the release of Claude Fable 5, Anthropic's most capable model to date, which analysts say drove much of the enterprise momentum captured in May's data.
Claude Fable 5: The 'Mythos' Class Breakthrough in Reasoning
Anthropic's Claude Fable 5, launched June 9, 2026, represents the company's most capable model to date — and a key driver behind its surge in enterprise adoption.
Classified under Anthropic's new "Mythos" tier, Fable 5 posted a GDPval-AA knowledge work score of 1932, edging out the previous flagship Claude Opus, which scored 1890 on the same benchmark. Vision performance also advanced sharply, with the model reaching 29.8% on the GDPdf benchmark, signaling measurable gains in document and image understanding.
Fable 5 powers both Claude Code — a tool developers are already using to tackle complex software tasks — and the collaborative Cowork product, both of which Anthropic credits with driving business momentum. "Claude is increasingly indispensable to our growing global community of customers," said Anthropic CFO Krishna Rao. "This funding will help us serve the historic demand we are experiencing."
That demand is also reshaping Anthropic's hiring pipeline. The company has expanded anthropic careers listings globally as it scales teams to support Fable 5's deployment. Further operational moves — including new office locations and strategic acquisitions — appear poised to accelerate that trajectory.
Strategic Expansion: Milan Offices and Recursive Research
Anthropic is matching its technical momentum with operational scale, opening a new Milan office and acquiring runtime tooling company Bun to deepen the Claude Code ecosystem. The Bun acquisition signals a direct investment in developer infrastructure, positioning Claude Fable 5 as not just a reasoning model but a full-stack coding platform.
Funding supports the push. Anthropic's Series H round secured $65 billion at a $965 billion post-money valuation — capital the company is deploying across geographic expansion and research.
On the research front, Anthropic Institute work on recursive self-improvement — AI systems that iteratively refine their own architecture — is shaping how the company governs future model generations. Alongside this, Claude's Constitution is being actively updated to address agentic knowledge work, where models operate with greater autonomy over multi-step tasks.
With Claude Sonnet 4.5 expected in coming months, observers will watch whether Anthropic can sustain both its safety commitments and its newly claimed enterprise lead.
