Anthropic raises $65B Series H at $965B valuation, leapfrogs OpenAI

Anthropic closed a $65 billion Series H on May 28, 2026, at a $965 billion post-money valuation, narrowly edging past OpenAI’s $852 billion mark from March and making Anthropic the most valuable private company in the world. The size of the round, the implied 2.5x markup off February’s $380 billion Series G, and the company’s stated framing as a likely final private raise point at an IPO window opening in the next few quarters.

What the round looks like

The Series H was co-led by ten funds: Altimeter Capital, Dragoneer, Greenoaks, Sequoia Capital, Capital Group, Coatue, D1 Capital Partners, GIC, ICONIQ, and XN. According to TechCrunch’s sourcing, each of the lead investors put in more than $2 billion. Significant investors include AMP PBC, Baillie Gifford, Blackstone, Brookfield, D.E. Shaw Ventures, DST Global, Fidelity, General Catalyst, Insight Partners, Jane Street, Lightspeed, MGX, T. Rowe Price, and Temasek. The round also folds in $15 billion of previously committed hyperscaler capital, including $5 billion from Amazon that was announced in April.

Strategic infrastructure partners (Samsung, SK Hynix, and Micron) joined the round directly, a structure that ties Anthropic’s funding base to its memory and storage supply chain rather than only to its compute supply chain. That is the durable read: the cap table now includes both the cloud platforms training Claude and the chip suppliers feeding those clouds.

Series H is rare enough that the named precedents (Facebook, Lyft, Discord, Slack) are mostly companies that grew well past the standard venture exit window. Databricks reached a comparable lane only after grinding through Series I, J, and K. The shape of Anthropic’s letter run suggests Anthropic has reached the same lane in roughly half the time.

Where the money goes

The announcement names three priorities: safety and interpretability research, expanded compute to meet Claude demand, and continued investment in products and partnerships. The compute line is the largest in dollar terms, and Anthropic disclosed three concurrent capacity deals that frame the scale.

1. Amazon: up to five gigawatts of new capacity. AWS remains the primary cloud provider and training partner. The five-gigawatt figure puts Anthropic in the same compute-procurement band as the largest hyperscaler-internal workloads. For Claude API and Claude Code users on AWS Bedrock, the practical read is that capacity headroom should rise faster than demand over the next several quarters.
2. Google and Broadcom: five gigawatts of next-generation TPU capacity. The Google deal is the first time Anthropic has signalled a multi-gigawatt TPU commitment alongside an AWS Trainium commitment. Workloads that ride TPUs typically get a distinct cost-performance profile from GPU-based inference, and the practical effect for builders is broader hardware diversity behind the same Claude endpoint.
3. SpaceX: GPU access in Colossus 1 and Colossus 2. Colossus is the xAI training cluster that SpaceX absorbed earlier this year. Anthropic buying GPU time inside Colossus is a notable cross-vendor arrangement given xAI’s competitive position, and it suggests Anthropic is prioritizing raw GPU availability over cleaner vendor boundaries.

Anthropic also confirmed Claude is the first frontier model available across all three major clouds (AWS, Google Cloud, and Azure). For teams building on Claude through an existing cloud account, the procurement story is now genuinely “use the cloud you already have a contract with”.

The revenue and IPO picture

Run-rate revenue crossed $47 billion in May 2026, up from the figure disclosed at the February Series G. The company expects to be cash-flow positive by 2028, a target that was pushed back earlier this year as compute and training costs climbed faster than the revenue line. Brad Gerstner of Altimeter cited “large-scale adoption among the world’s most demanding organizations” in his commentary, and Alfred Lin of Sequoia named complex workflow handling at Global 5000 customers as the wedge.

TechCrunch reports Anthropic is preparing an IPO filing in the coming months, alongside an OpenAI filing that is expected within weeks. SpaceX, post-xAI merger, is targeting a $2 trillion valuation in its own pending IPO. The shape of the AI capital market in the second half of 2026 looks like three mega-listings concentrated in roughly the same window, which carries pricing risk for whichever company files last.

The competitive backdrop matters for the IPO narrative. OpenAI’s $122 billion Series at $852 billion in March set the high-water mark Anthropic just cleared. Bloomberg’s framing (that Anthropic eclipsed OpenAI on valuation for the first time) is the headline analysts will return to when the S-1s drop. The pre-IPO valuation gap is small enough that it could invert again before the listings price.

What to watch over the next two quarters

The Series H is now the base case, but the operating signals that justify it are still developing. The key signals to watch are:

• Claude Opus 4.8 adoption shape. Released the same day as the round, Opus 4.8 emphasizes agentic tasks, advanced coding, and self-correction. The interesting question is whether the gains push Claude Code’s share of agentic-coding usage further past competitors, or whether OpenAI’s next flagship narrows the gap before the IPO window.
• Cybersecurity model rollout. Anthropic is reportedly preparing a wider release of models comparable to its limited-availability Mythos cybersecurity model. That is a clear new category move, and the size and speed of the rollout will shape how the IPO story positions Anthropic beyond the general-purpose chat and coding markets.
• TPU and SpaceX capacity onboarding. Multi-gigawatt compute deals take quarters to come online. Anthropic’s ability to absorb the new TPU and Colossus capacity without prolonged availability blips on Claude endpoints is the practical operating test of the round’s compute thesis.
• Cash-flow timeline. The 2028 target was already pushed back once. Any further movement, or any disclosure that pulls it forward, will weigh heavily on the IPO range.

Stackmaven’s follow-up coverage lands on or around August 27, 2026.

Sources cited

1. Anthropic: Series H announcement (May 28, 2026) www.anthropic.com
2. TechCrunch: Anthropic raises $65 billion, nears $1T valuation ahead of IPO techcrunch.com
3. Bloomberg: Anthropic raises at $965B valuation, eclipsing OpenAI www.bloomberg.com
4. PitchBook: Anthropic bests OpenAI in valuation race, hitting $965B with Series H pitchbook.com