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  • Mark Zuckerberg, Priscilla Chan, and Alex Rives on CZI Biohub, Open-Source AI, and Building World Models of Biology to Cure All Disease

    Mark Zuckerberg, Priscilla Chan, and AI researcher Alex Rives sat down with the No Priors podcast to explain why CZI Biohub became the primary focus of their philanthropy, why they committed $500 million to a virtual biology initiative, and why they are giving the resulting AI models away as open source instead of building a company. The conversation moves from a goal that Nobel laureates once laughed at, curing, preventing, and managing all disease by the end of the century, to a concrete technical strategy: build world models of biology layer by layer, from proteins to cells to whole systems, and put them in every scientist’s hands.

    TLDW

    This is the clearest public articulation yet of how the Chan Zuckerberg Initiative thinks about AI and biology. The throughline starts a decade ago when Zuckerberg and Chan asked scientists how to cure all disease and learned the real bottleneck was tooling, siloed labs, and unshared knowledge, not a lack of ambition. That insight produced the Human Cell Atlas, the CELLxGENE annotation tool, and a corpus of single-cell transcriptomics that large language models could finally make sense of. Now Biohub couples a frontier AI lab with frontier wet-lab biology under one roof across San Francisco, New York, and Chicago, organized around the virtual biology initiative and the long-term goal of a virtual cell. Alex Rives, the AI researcher behind the ESM protein language models, walks through their newly released ESM-based world model of protein biology: trained on billions of protein sequences, it predicts atomic-resolution structures blazingly fast, folded over 1.1 billion proteins, designs novel proteins and single-chain antibodies as an emergent property, and found nanomolar binders in a single 96-well plate. The discussion covers mechanistic interpretability as a way to extract genuinely new biological knowledge, personalized medicine driven by understanding the chain from gene variant to protein to disease, predicting off-target toxicity before human trials, rare-disease patient organizing, the baby KJ CRISPR case, biosafety tradeoffs of open source, talent and why frontier biology plus frontier AI is a recruiting moat, and what success looks like five years out.

    Thoughts

    The most important claim in this conversation is also the easiest to miss because it is delivered casually: protein design is an emergent property of a model that was never asked to design proteins. Rives is explicit that they did not build a model for antibodies and did not build a model to bind a particular target. They built a model that understands proteins, trained on raw sequence with a next-token objective, and protein design, structure prediction, and antibody generation fell out of it. That is the language-model bet transplanted into biology, and the fact that it produced nanomolar binders, the threshold for actual therapeutic activity, in a single 96-well plate rather than a high-throughput screen of millions is the kind of result that quietly resets what a small team can attempt. If that generalizes, the binding curve for “design a molecule” bends the same way the cost curve for “write working code” did.

    What makes the strategy coherent, rather than just a well-funded AI lab, is the insistence that the wet lab and the AI lab are a single effort. Most of biology’s useful data does not exist on the internet the way human language does. You cannot pay a factory to produce it. Someone has to invent the cellular engineering in New York, the inflammation-sensing devices in Chicago, the translucent-zebrafish imaging, and that is the actual product of frontier biology: new instruments that generate data nobody has ever seen, which in turn make new classes of models possible. This is the part venture-backed competitors will struggle to replicate, because it requires patience measured in 10 to 15 year horizons and a willingness to spend on data generation that has no business model attached. Zuckerberg is almost dismissive about it, noting they could probably run it as a business but that not having to think about monetization is strategically simplifying. The nonprofit structure is not charity window-dressing here. It is what lets them release the models as an open discovery engine and harness the entire academic and biotech field rather than competing with it.

    The mechanistic interpretability thread deserves more attention than it will get. Interpretability has mostly been a safety and alignment story for language models, a way to peer inside the black box and check that the representations match our understanding of the world. Rives flips it: the protein models have been trained on both known and unknown biology, billions of sequences including proteins we understand nothing about, and they are building representations that connect the unknown proteins to the known ones through an underlying structural grammar. The promise is that interpretability becomes a discovery tool, not just an audit tool. You open the box and find biology the field has not characterized yet, the mechanism of action for a treatment, a system in the body nobody mapped. That is a fundamentally more optimistic use of the same toolkit, and it is the part of the launch Sarah Guo and Elad Gil both flag as the most interesting.

    Chan’s framing of personalized medicine is worth sitting with because it reframes the entire goal away from “cure disease X.” She wants to treat the individual as an individual: understand this person’s genetics, their risk profile, the mechanistic chain from a specific gene variant through a protein to a disease process, and then design a drug bespoke to them. The current reality she describes, sitting in PubMed reading a paper’s supplement asking “am I represented in this cohort,” guessing whether a drug that kind of impacts a pathway that is probably implicated might do something, is a brutal and accurate picture of how non-standard cases are actually handled today. The vision is generalizable tools delivering personalized answers, which is the same put-the-tool-in-the-individual’s-hands philosophy Zuckerberg applies to open-source AI and, by his own analogy, to social media. Whether you find that analogy reassuring or not, the consistency of the worldview is real: they genuinely do not believe in a central super-intelligence solving science, and the whole architecture follows from that.

    The honest gap they name is the clinic. Chan is candid that the science will start moving fast but that translating to patients requires changing how clinical research itself works, and that part is still shaping up. The most interesting near-term lever is not a virtual FDA trial but the recruitment and economics flip for rare disease: patient groups self-organizing registries, biobanks, and natural-history studies, compressing timelines from decades to a handful of years, paired with models that lower the cost of generating a candidate. The baby KJ case, a custom CRISPR therapeutic to edit a single mutation, delivered to liver cells specifically because that target was deliverable, is the proof of concept for why disease selection and delivery creativity matter as much as the molecule. The molecule is becoming the cheap part. The rest of the chain is where the next decade of work actually sits.

    Key Takeaways

    • CZI Biohub is now the primary philanthropic focus of the Chan Zuckerberg Initiative, a shift the team formalized in the past year.
    • They committed $500 million to the virtual biology initiative, the unifying theme across the Biohubs.
    • The original goal, set roughly 10 years ago, was to cure, prevent, and manage all disease by the end of the century. Zuckerberg now thinks “end of the century” is too conservative.
    • Nobel Prize winning scientists initially laughed at the all-disease ambition. When pressed for why it was impossible, the real answers were silos, locked-up unpublished information, and the inability to build shared tools.
    • The recurring example: a postdoc builds a great tool, it lives on their computer, they graduate, and the tool is gone. Shared, durable tooling was the missing layer.
    • CZI is explicit that they are not the ones who will cure diseases. Their role is building tools that accelerate the entire scientific field so the field collectively cures them.
    • The first request for application was single-cell sequencing, funding methods so scientists could share how to do it.
    • That work led to funding the Human Cell Atlas, now one of the largest databases of single-cell transcriptomics.
    • They built CELLxGENE, a simple annotation tool, around which a community formed and contributed data CZI had nothing to do with creating. It is now a corpus underpinning many transcriptomic models.
    • Critics called the data gathering “stamp collecting.” The arrival of large language models, which can make sense of large amounts of data, answered that critique.
    • The ambition is to move biology from a discovery-based science to an engineering-based science, systematically understanding how living cells work and why things go wrong.
    • Biohub couples a frontier AI lab with a frontier biology effort. Unlike language models, biology lacks abundant internet-scale data, so new science is required to generate the data the models need.
    • The Biohubs are specialized: New York focuses on cellular engineering, Chicago builds devices to measure things like inflammation, plus imaging work and translucent-zebrafish development studies.
    • Alex Rives, who built the ESM protein language models and founded EvolutionaryScale after working at Meta FAIR, now leads the AI effort. The team raised venture capital before joining CZI’s nonprofit structure.
    • The strategy is hierarchical: model proteins first, then cells, then whole systems, because you cannot understand cells without understanding protein interactions.
    • They collect data strategically to bridge across the hierarchy, for example spatial transcriptomics showing where RNA localizes within a cell, and sensors that observe cell-to-cell communication.
    • The newly released ESM-based model is a world model of protein biology, trained on billions of protein sequences, predicting atomic-resolution structure extremely fast at a Pareto-optimal frontier of speed and accuracy.
    • They folded over 1.1 billion proteins and predicted their structures, identifying connecting features through mechanistic interpretability.
    • The model hits state of the art on structure prediction benchmarks, especially protein-protein and protein-antibody interactions, which are critical for therapeutic design.
    • Protein and antibody design are emergent properties. They designed a model to understand proteins, not to bind any specific target, and design capability fell out of it.
    • In one experiment, they selected from hundreds of thousands of digital trajectories, synthesized 96 proteins in a single well plate, and found nanomolar binders, the threshold for therapeutic activity.
    • Results were validated with the Biohub’s cryo-EM microscopes and structural biology center, confirming function and atomic-resolution binding interfaces.
    • Mechanistic interpretability is reframed as a discovery tool: open the black box to find biology nobody has characterized, not just to audit the model.
    • Chan’s vision of personalized medicine: understand a person’s genetics, the mechanistic chain from gene variant to protein to disease, then design a bespoke drug and intervene.
    • A comprehensive model of how cells work could predict off-target effects, like a receptor on kidney cells causing renal toxicity, before human trials.
    • They study systems rather than individual diseases. Inflammation is a major Chicago focus because it connects to many diseases.
    • A typical drug trial runs about 15 years and $1.5 billion. Only roughly $50 million is the molecule and preclinical work. The other $1.45 billion is drug development, much of it gated on regulation, recruitment, and failures from toxicity or absorption.
    • The baby KJ case at CHOP delivered a custom CRISPR therapeutic to edit a single mutation, chosen carefully because his liver cells were a deliverable target.
    • CZI’s “Rare As One” program supports rare-disease patient groups self-organizing registries, biobanks, and even their own clinical trials, compressing gene-therapy timelines from decades to 3 to 5 years.
    • Letting people opt in to frontier trials, while preserving historical vetting for the general population, is named as a key shift that could accelerate biology.
    • The open-source philosophy mirrors Zuckerberg’s broader ethos: empower individuals with tools rather than centralizing power in a few institutions or a single super-intelligence.
    • Biosafety is acknowledged as a real consideration that open-source biology will need to balance and handle carefully.
    • On talent: AI researchers could join any frontier lab, but no other organization pairs frontier biology with frontier AI, which is the recruiting moat.
    • You do not need a huge team. Zuckerberg argues real AI progress can come from a strong group of a dozen or a couple dozen people.
    • Researchers have been connecting the released model to agentic systems to automate the entire protein design process.
    • The next big challenge is the virtual cell: a system that models the proteomic, genetic, and transcriptomic layers and connects them to phenotype, generalizing to interventions it was never trained on.
    • Like every lab, Biohub is compute and data constrained, constantly deciding whether to double down on proteins or push further into cellular work.
    • Five-year success: a hierarchical set of world models of biology and doing the highest-quality, uniquely contributive work in the world, a setup the team believes no other organization has.
    • The biggest update of the past year: formalizing Biohub as the philanthropy’s core, and flipping leadership from biologists interested in technology to an AI researcher with a biology background.
    • Zuckerberg’s read on the broader industry: the exponential curve is on track and still accelerating, which validates making a very big long-term investment.

    Detailed Summary

    From “cure all disease” to a tooling problem

    The origin story is a decade old. Zuckerberg and Chan wanted to build an organization that could cure, prevent, and manage all disease by the end of the century, and a series of meetings with famous, Nobel Prize winning scientists produced laughter rather than encouragement. Instead of retreating, they kept asking why it was impossible. The answers, once scientists relented, were not about biology being too hard. They were about how science is organized: researchers work in silos, published information gets locked up for long periods, and there is no good way to build and share durable tools. The image that stuck was a postdoc building an excellent tool that lives on a single computer and vanishes when that person graduates. The bottleneck was infrastructure and shared knowledge, and that is where CZI decided it could contribute.

    The path from single-cell sequencing to a world model

    The original Biohub model brought engineers and scientists together across universities for long-term tool development, and it worked. CZI’s first request for application targeted single-cell sequencing, funding the methods so scientists could share how to read the RNA transcribed in individual cells. That seeded the Human Cell Atlas, now one of the largest single-cell transcriptomics databases. When annotation became a bottleneck, CZI built CELLxGENE, a simple annotation tool, and a community formed around it and contributed data CZI never funded. Critics dismissed it as stamp collecting, gathering bits of data without extracting wisdom. Then large language models arrived and demonstrated they could make sense of exactly that kind of large-scale data, and Chan describes the delight of realizing the missing engine had appeared.

    Frontier AI married to frontier biology

    The unifying theme is the virtual biology initiative, and the structural insight is that the AI effort and the wet-lab effort are a single integrated organization, not two collaborating ones. Biology lacks the internet-scale data that language models enjoy. You cannot buy the data from a factory. So Biohub invents the science that generates it: cellular engineering in New York to record what happens inside the body, devices in Chicago to measure inflammation, imaging to visualize the previously invisible, and translucent zebrafish to watch development unfold across cells as the brain forms. Each new instrument creates a new dataset, which enables a new class of model. Rives, who built the ESM models and founded EvolutionaryScale before joining, frames this as the start of a new era of science, where systems that predict the next token can learn world models of biology from the data, provided you build at the right scale with the right people.

    Building biology hierarchically

    The team is deliberate that each layer of biology is qualitatively different and must be built up in order. You cannot jump to cells without understanding protein interactions, and you cannot model the immune system without first understanding cells. So the approach starts with the building blocks, the proteins, and ladders upward. The advantage of a single integrated effort is the ability to gather data that connects the hierarchy: spatial transcriptomics that show where RNA localizes inside a cell, sensors that capture cell-to-cell communication, developmental imaging in zebrafish. That connective tissue is what lets the modeling generalize across levels. The interviewer, a former wet-lab biologist with a PhD, notes that the reductionist and systems camps of biology historically never worked together deeply, and that bridging them is one of the genuinely novel things about the effort.

    The ESM-based protein world model

    The launch at the center of the conversation, roughly a week old at recording, is an open system for scientific discovery in protein biology: a language-model-based world model trained on billions of protein sequences. It learns emergent representations of protein biology and predicts atomic-resolution structure at blazing speed, sitting on a Pareto-optimal frontier of speed and accuracy. They folded over 1.1 billion proteins and used mechanistic interpretability to identify features connecting them. It reaches state of the art across structure-prediction benchmarks, with particular strength on protein-protein and protein-antibody interactions that matter for therapeutics. The headline result: they used the model to design proteins and single-chain antibodies digitally, selected from hundreds of thousands of trajectories, synthesized just 96 in a single well plate, and found nanomolar binders, replacing high-throughput screens of millions of antibodies. Validation came from the Biohub’s cryo-EM structural biology center, confirming both function and the atomic-resolution binding interfaces.

    Interpretability as discovery, and personalized medicine

    Rives reframes mechanistic interpretability, usually aimed at language models, as a way to extract new biological knowledge. The protein models are trained on both known and unknown biology and develop representations that connect uncharacterized proteins to understood ones through an underlying structural grammar. Opening that black box could reveal systems in the body or mechanisms of action for treatments that the field has never mapped. Chan connects this to a personalized-medicine vision: understand an individual’s genetics and the mechanistic chain from gene variant to protein to disease, then design a bespoke intervention. She contrasts it with today’s reality of reading PubMed supplements and guessing whether you are represented in a study cohort. For some diseases, simply knowing which gene variants cause disease is already empowering. For others, the chain is understood and the missing piece is the ability to change a protein’s function, which is where designed proteins could actually cure.

    Drug development, off-target effects, and rare disease

    The interviewers press on translation, noting a typical trial runs 15 years and $1.5 billion, with only about $50 million in the molecule and preclinical work and the rest in development gated on regulation, recruitment, toxicity, and absorption failures. Chan’s hope is that comprehensive cell models predict off-target effects, like an unanticipated receptor on kidney cells causing renal toxicity, before human trials. They study systems such as inflammation and the immune system rather than chasing individual diseases. The baby KJ case at CHOP, a custom CRISPR therapeutic editing a single mutation delivered to liver cells, illustrates how careful disease and delivery selection unlocks first applications. The “Rare As One” program shows rare-disease patient groups self-organizing registries, biobanks, and trials, compressing timelines from decades to a few years, and the molecule becoming cheap flips the economics of the long tail of niche diseases.

    Open source, talent, and the five-year view

    Zuckerberg ties the open-source posture to a consistent worldview: empower individuals with tools rather than centralizing intelligence in a few institutions. He does not believe in a single super-intelligence solving all of science, and sees decentralization, the same instinct behind giving people a voice, as how progress is historically made, with biosafety as a real tradeoff to manage. On talent, the pitch is that frontier biology attached to frontier AI is work you cannot do anywhere else, and that meaningful progress needs only a dozen or two dozen strong people, not thousands. Researchers are already wiring the model into agentic systems to automate design. The next frontier is the virtual cell, modeling proteomic, genetic, and transcriptomic layers and connecting them to phenotype with enough generality to answer untrained questions. Five years out, success is a hierarchical set of world models and doing uniquely high-quality work, with Chan adding that the teams are now “arms linked,” directed and interlocked rather than merely moving in the same direction.

    Notable Quotes

    “We didn’t design a model for antibodies. We didn’t design a model to be able to bind one particular target. We just designed a model that could understand proteins.”

    Alex Rives, on protein design emerging from a general model

    “The theory isn’t that we’re going to cure the diseases. We’re not. It’s that we want to help accelerate the pace of progress for the whole scientific field.”

    Mark Zuckerberg, on why CZI builds tools rather than cures

    “My goal is to be able to treat the individual as an individual, understand the mechanisms and be able to intervene.”

    Priscilla Chan, on the vision for personalized medicine

    “It’s not just like there’s some factory somewhere that you can pay to produce the data. You actually need to invent new novel scientific approaches.”

    Mark Zuckerberg, on why frontier biology has to generate its own data

    “If we could design a protein to actually change the physiology, then we can actually cure someone.”

    Priscilla Chan, on the payoff of protein design

    “You open up the black box and you can actually understand the biology that the model is representing.”

    Alex Rives, on mechanistic interpretability as a discovery tool

    “We don’t believe in this like very centralized future where there should be a small number of institutions that basically are advancing all this stuff.”

    Mark Zuckerberg, on the open-source ethos behind Biohub

    “Before we had amazing teams moving generally in the same direction. But now we are arms linked moving together.”

    Priscilla Chan, on how the Biohub teams now operate under Alex Rives

    Watch the full conversation with Mark Zuckerberg, Priscilla Chan, and Alex Rives on the No Priors podcast here.

    Related Reading

    • CZI Biohub Network the official program page for the San Francisco, New York, and Chicago Biohubs discussed throughout.
    • EvolutionaryScale Alex Rives’s lab and the home of the ESM protein language models behind the world model in this conversation.
    • Human Cell Atlas the single-cell transcriptomics effort CZI funded that became foundational to modern cell modeling.
    • AlphaFold (Wikipedia) background on the protein-folding breakthrough referenced as an early proof that structure prediction was tractable at scale.
    • Rare As One CZI’s program supporting patient-led rare-disease research organizations described near the end of the talk.

  • Anthropic Raises $65 Billion Series H at $965 Billion Valuation to Fund AI Safety Research and Massive Compute Expansion

    Anthropic has closed one of the largest private financing rounds in the history of technology, raising $65 billion in Series H funding at a $965 billion post-money valuation. The round, announced on May 28, 2026, lands as demand for Claude reaches what the company calls historic levels, and it positions Anthropic to pour fresh capital into safety research, compute, and the products that enterprises now lean on every day.

    TLDR

    Anthropic raised $65 billion in its Series H at a $965 billion post-money valuation, with Altimeter Capital, Dragoneer, Greenoaks, and Sequoia Capital leading and Capital Group, Coatue, D1 Capital Partners, GIC, ICONIQ, and XN co-leading, alongside $15 billion in previously committed hyperscaler investment that includes $5 billion from Amazon. The raise follows Anthropic crossing $47 billion in run-rate revenue earlier in May 2026, and it funds three priorities named by CFO Krishna Rao: advancing safety and interpretability research, expanding compute capacity to meet growing Claude demand, and scaling the products and partnerships customers depend on. On the infrastructure side, the company is locking in gigawatt-scale compute through 5 gigawatts with Amazon, 5 gigawatts of TPU capacity via Google and Broadcom, GPU access from SpaceX, and supply from partners Micron, Samsung, and SK hynix, while Claude remains available across all three major cloud platforms, AWS, Google Cloud, and Microsoft Azure, with widespread enterprise adoption across industries.

    Thoughts

    Start with the number that everyone will fixate on. A $965 billion post-money valuation against $47 billion in run-rate revenue is roughly 20 times sales, and for a company growing this fast that multiple is not the interesting part. The interesting part is that run-rate revenue crossed $47 billion earlier this month, which means the denominator is moving so quickly that the multiple is already stale. Investors are not pricing the business Anthropic is today. They are pricing the slope. A 20x multiple on a number that may double again inside a year is a very different bet than 20x on a flat line, and the lead names here (Altimeter, Dragoneer, Greenoaks, Sequoia, with Capital Group, Coatue, GIC and others co-leading) are not the kind of capital that pays for nostalgia. They are paying for the second derivative.

    But the real story is not the valuation. It is the compute. Read the infrastructure list carefully and you see the actual problem this round solves: 5 gigawatts from Amazon, 5 gigawatts of TPU capacity through Google and Broadcom, GPU access from SpaceX, and memory supply locked down with Micron, Samsung, and SK hynix. That is more than 10 gigawatts of secured power and silicon. The constraint on frontier AI in 2026 is no longer talent or even algorithms. It is electricity, land, and the multi-year queue for advanced packaging and high-bandwidth memory. You cannot buy 10 gigawatts on a quarterly basis. You reserve it years out, and you need the balance sheet to make those commitments credible. A $65 billion raise is, in plain terms, the down payment that lets Anthropic sign for capacity nobody can conjure on demand. The money is downstream of the megawatts.

    The diversification across that compute stack matters as much as the size. By splitting between Amazon’s infrastructure, Google and Broadcom’s custom TPUs, and SpaceX-supplied GPUs, Anthropic is refusing to become hostage to any single supplier’s roadmap or pricing. Custom silicon through Broadcom in particular is a bet on bending the cost curve, because the long-term economics of serving Claude at this scale depend on dollars per token, not just on raw availability. Anyone who has watched cloud lock-in play out over the last decade understands the move. Optionality at the hardware layer is leverage, and leverage is what keeps margins from being dictated by whoever owns the only fab slot you can reach.

    It is worth pausing on the fact that the round explicitly funds safety and interpretability research alongside scaling, and not as a footnote. Most companies treat safety spend as a cost center to be minimized once growth kicks in. Naming it first, ahead of compute and products, is a statement about where Anthropic believes its durable advantage sits. If models keep getting more capable, the binding constraint on deployment inside regulated industries (finance, healthcare, government) becomes trust, not intelligence. Interpretability is the work that turns a black box into something an enterprise risk committee can actually sign off on. Framed that way, safety research is not philanthropy subtracted from the bottom line. It is the thing that unlocks the most lucrative and defensible parts of the market, and pairing it with the scaling budget is the tell.

    Finally, look at distribution. Claude now ships on all three major clouds at once: AWS, Google Cloud, and Microsoft Azure. In a market where most frontier labs are tethered to a single hyperscaler, being available everywhere enterprises already run their workloads is a structural edge. It removes the procurement friction of asking a customer to adopt a new vendor relationship, and it means Anthropic competes on the merits of the model rather than on which cloud a buyer happened to standardize on years ago. Combine that omnipresent distribution with the compute reservations and the explicit safety mandate, and the shape of the strategy is clear. This is not a company buying time. It is a company buying the three things that actually compound: capacity that cannot be rushed, trust that cannot be faked, and reach into every place where work already happens.

    Key Takeaways

    • Anthropic raised $65 billion in its Series H funding round, one of the largest private financings in the history of the technology industry.
    • The round set Anthropic’s post-money valuation at $965 billion, placing the company within reach of the $1 trillion mark.
    • Altimeter Capital, Dragoneer, Greenoaks, and Sequoia Capital led the Series H round.
    • Capital Group, Coatue, D1 Capital Partners, GIC, ICONIQ, and XN served as co-leads on the investment.
    • The new capital builds on $15 billion in previously committed hyperscaler investments, which includes $5 billion from Amazon.
    • Anthropic crossed $47 billion in run-rate revenue earlier in May 2026, reflecting the surging commercial demand for Claude.
    • A core priority for the funding is to advance Anthropic’s safety and interpretability research.
    • The company will use the capital to expand compute capacity in order to meet growing demand for Claude.
    • Anthropic plans to scale the products and partnerships that customers depend on across its business.
    • CFO Krishna Rao said the funding will help Anthropic serve the historic demand it is experiencing, stay at the research frontier, and bring Claude to more of the places where work happens.
    • Amazon is providing 5 gigawatts of compute capacity as part of Anthropic’s infrastructure expansion.
    • Google and Broadcom are supplying 5 gigawatts of TPU capacity to power Claude’s growth.
    • SpaceX is contributing GPU access to Anthropic’s compute footprint.
    • Micron, Samsung, and SK hynix are partnering with Anthropic on memory and infrastructure to support its scaling needs.
    • Claude is available on all three major cloud platforms, AWS, Google Cloud, and Microsoft Azure.
    • Anthropic reports widespread enterprise adoption of Claude across a broad range of industries.

    Detailed Summary

    The Raise and the Valuation

    Anthropic has raised $65 billion in Series H funding, a round that values the company at $965 billion on a post-money basis. The size of the raise places it among the largest private financing events the technology industry has ever seen, and the valuation pushes Anthropic to the doorstep of the trillion dollar mark. The capital arrives at a moment when demand for the company’s Claude models has accelerated sharply, and the round is built to fund the response to that demand rather than simply mark a milestone. Anthropic framed the financing in its Series H announcement as the fuel for staying at the research frontier while scaling the infrastructure and products that customers increasingly rely on.

    Who Put In the Money

    The Series H was led by Altimeter Capital, Dragoneer, Greenoaks, and Sequoia Capital, a group that combines deep growth-stage technology experience with conviction in Anthropic’s long-term trajectory. Joining as co-leads were Capital Group, Coatue, D1 Capital Partners, GIC, ICONIQ, and XN, a roster that spans crossover funds, sovereign wealth, and institutional investors. Beyond the new equity, Anthropic pointed to $15 billion in previously committed hyperscaler investment, including $5 billion from Amazon. Taken together, the investor base reflects a mix of financial backers and strategic partners with a direct stake in seeing Claude reach more customers and more compute.

    Revenue at $47 Billion Run-Rate

    Underpinning the valuation is a business that has scaled with unusual speed. Anthropic crossed a $47 billion run-rate revenue figure earlier in May 2026, a number that signals how quickly enterprises and developers have adopted Claude across their workflows. Run-rate revenue annualizes the company’s most recent performance, and at this level it puts Anthropic firmly among the fastest growing software businesses on record. That financial momentum is the practical justification for both the round’s size and the near trillion dollar valuation investors were willing to support.

    The Compute Buildout

    A large share of the strategy behind the raise centers on securing compute at enormous scale. Anthropic detailed a set of infrastructure partnerships designed to keep pace with Claude demand. Amazon is providing 5 gigawatts of capacity, while Google and Broadcom together are supplying 5 gigawatts of TPU capacity. SpaceX is contributing GPU access, broadening the range of silicon Anthropic can draw on. Supporting the buildout on the hardware supply side are Micron, Samsung, and SK hynix, the memory and component partners whose output is essential to standing up data centers at this magnitude. The combined picture is a company assembling power, chips, and supply chain commitments measured in gigawatts rather than racks.

    Where the Money Goes

    Anthropic outlined three priorities for the new capital. The first is to advance safety and interpretability research, continuing the work of understanding how models behave and ensuring they remain reliable as they grow more capable. The second is to expand compute capacity to meet the growing demand for Claude, the practical engine behind the infrastructure commitments above. The third is to scale the products and partnerships that customers depend on, deepening the company’s reach into the tools and platforms where work actually happens. Krishna Rao, Anthropic’s chief financial officer, said the funding “will help us serve the historic demand we are experiencing, stay at the research frontier, and bring Claude to more of the places where work happens.”

    Claude Everywhere

    The funding lands on top of a distribution footprint that already spans the major cloud ecosystems. Claude is available on all three leading cloud platforms, AWS, Google Cloud, and Microsoft Azure, which means enterprises can reach the models through whichever provider they have standardized on. That availability has translated into widespread enterprise adoption across industries, from software and finance to healthcare and beyond. By being present everywhere developers and businesses already operate, Anthropic positions Claude not as a destination customers must travel to but as a capability woven into the platforms they use every day.

    Notable Quotes

    This funding will help us serve the historic demand we are experiencing, stay at the research frontier, and bring Claude to more of the places where work happens.

    Krishna Rao, CFO at Anthropic, on the purpose of the Series H round.

    Advance safety and interpretability research, expand compute capacity to meet growing Claude demand, and scale products and partnerships customers depend on.

    How Anthropic describes its use of funds from the round.

    For the full details on the round, the lead and co-lead investors, and how Anthropic plans to deploy the capital across safety research, compute, and products, read the full announcement here.

    Related Reading

    • Anthropic, the AI safety and research company behind Claude that raised this Series H round.
    • Sequoia Capital, one of the lead investors anchoring the financing.
    • Amazon Web Services, one of the three major cloud platforms where Claude is available and the source of a $5 billion investment.
    • Google Cloud TPUs, the tensor processing units behind the 5 gigawatts of TPU capacity in the Google and Broadcom partnership.
    • AI safety, the research field at the center of how Anthropic says it will use the new funding.

  • Krishna Rao on Anthropic Going From 9 Billion to 30 Billion ARR in One Quarter and the Compute Strategy Powering Claude

    Krishna Rao, Chief Financial Officer of Anthropic, sat down with Patrick O’Shaughnessy on Invest Like the Best for one of the most detailed public looks yet at the operating engine behind Claude. He covers how Anthropic compounded from $9 billion of run rate revenue at the start of the year to north of $30 billion by the end of Q1, why he spends 30 to 40 percent of his time on compute, the playbook for buying gigawatts of AI infrastructure across Trainium, TPU, and GPU platforms, how Anthropic prices its models, why returns to frontier intelligence keep climbing, and what the Mythos release tells us about the cyber capabilities of the next generation of Claude.

    TLDW

    Anthropic is running the most compute fungible frontier lab in the world, with active deployments across AWS Trainium, Google TPU, and Nvidia GPU, and an internal orchestration layer that lets a chip serve inference in the morning and run reinforcement learning the same evening. Krishna Rao explains the cone of uncertainty that governs gigawatt scale compute procurement, the floor Anthropic refuses to drop below on model development compute, the Jevons paradox unlock from cutting Opus pricing, the 500 percent annualized net dollar retention from enterprise customers, the layer cake of long term deals with Google, Broadcom, Amazon, and the recent xAI Colossus tie up in Memphis, the phased release of the Mythos model in response to spiking cyber capabilities, the internal use of Claude Code to produce statutory financial statements and run a Monthly Financial Review skill, and why the team believes scaling laws are alive and well. The interview also covers fundraising history through Series D and Series E, the $75 billion already raised plus another $50 billion coming, talent density beating talent mass during the Meta poaching wave, and Rao’s belief that biotech and drug discovery represent the most exciting frontier for AI.

    Key Takeaways

    • Anthropic entered the year with about $9 billion of run rate revenue and ended the first quarter with north of $30 billion of run rate revenue, a more than 3x leap driven by model intelligence gains and the products built around them.
    • Compute is described as the lifeblood of the company, the canvas everything else is built on, and the most consequential class of decisions Rao makes. Buy too much and you go bankrupt. Buy too little and you cannot serve customers or stay at the frontier.
    • Rao spends 30 to 40 percent of his time on compute, even today, and the leadership team meets repeatedly on both procurement and ongoing compute allocation.
    • Anthropic is the only frontier language lab actively using all three major chip platforms in production: AWS Trainium, Google TPU, and Nvidia GPU. It is also the only major model available on all three clouds.
    • Flexibility is the central design principle. Anthropic builds flexibility into the deals themselves, into the orchestration layer that maps workloads to chips, and into compilers built from the chip level up.
    • The cone of uncertainty frames procurement. Small differences in weekly or monthly growth compound into wildly different two year outcomes, so the team plans across a range of scenarios rather than a single point estimate, and ranges toward the upper end while protecting downside.
    • Compute allocation across the company sits in three buckets: model development and research, internal employee acceleration, and external customer serving. A non negotiable floor protects model development even when customer demand is tight.
    • Anthropic estimates that if it cut off internal employee use of its own models, the freed compute could serve billions of dollars of additional revenue. It chooses not to, because internal use compounds into better future models.
    • Intelligence is multi dimensional, not a single IQ score. Anthropic measures real world capability through customer feedback, long horizon task performance, tool use, computer use, and speed at agentic tasks, not just leaderboard benchmarks that have largely saturated.
    • Each Opus generation, 4 to 4.5 to 4.6 to 4.7, delivers both capability improvements and an efficiency multiplier on token processing. New models often serve customers at a fraction of the prior cost while doing more.
    • Reinforcement learning is described as inference inside a sandbox with a reward function, so model efficiency gains directly improve internal RL throughput. The flywheel is tightly coupled.
    • Over 90 percent of code at Anthropic is now written by Claude Code, and a large share of Claude Code itself is written by Claude Code.
    • Anthropic shipped roughly 30 distinct product and feature releases in January and the pace has accelerated since.
    • Scaling laws, in Anthropic’s internal data, are alive and well. The team holds itself to a skeptical scientific standard and still does not see them slowing down.
    • Anthropic recently signed a 5 gigawatt deal with Google and Broadcom for TPUs starting in 2027, plus an Amazon Trainium agreement for up to 5 gigawatts, totaling more than $100 billion in commitments. A significant portion lands this year and next year.
    • A new partnership for capacity at the xAI Colossus facility in Memphis was announced just before the interview, aimed at expanding consumer and prosumer capacity.
    • Pricing has been remarkably stable across Haiku, Sonnet, and Opus. The biggest deliberate change was lowering Opus pricing, which produced a textbook Jevons paradox: consumption rose far faster than the price drop, and the new Opus 4.6 and 4.7 slot in at the same price point.
    • Mythos is the first model Anthropic chose to release in a phased way because of a sharp spike in cyber capability. In an open source codebase where a prior model found 22 security vulnerabilities, Mythos found roughly 250.
    • The Mythos release framework focuses on defensive use first, expands access over time, and is presented as a template for future capability spikes.
    • Anthropic now sells to 9 of the Fortune 10 and reports net dollar retention above 500 percent on an annualized basis. These are not pilots. Rao describes signing two double digit million dollar commitments during a 20 minute Uber ride to the studio.
    • The platform strategy is mostly horizontal. Anthropic will go vertical with offerings like Claude for Financial Services, Claude for Life Sciences, and Claude Security where it can demonstrate the model’s capabilities, but expects most application value to accrue to customers building on top.
    • Investors raised over $75 billion in equity since Rao joined, with another $50 billion in commitments tied to the Amazon and Google deals. Capital intensity is real, but the raises fund the upper end of the cone of uncertainty more than they fund current losses.
    • The Series E close coincided with the day the DeepSeek news broke, forcing investors to reassess their AI thesis in real time. Anthropic closed the round anyway.
    • Inside finance, Claude now produces statutory financial statements for every Anthropic legal entity, with a human checker. A library of more than 70 finance specific skills underpins workflows.
    • A custom Monthly Financial Review skill produces a 90 to 95 percent ready monthly close report, so leadership discussion shifts from reconciling numbers to debating implications.
    • An internal real time analytics platform called Anthrop Stats compresses weekly insight cycles from hours to about 30 minutes.
    • The biggest token user inside Anthropic’s finance team is the head of tax, focused on tax policy engines and workflow automation. The most senior people, not the youngest, are leading internal adoption.
    • Talent density beats talent mass. When Meta and others ran aggressive offer waves, Anthropic lost two people while peer labs lost dozens.
    • All seven Anthropic co founders remain at the company, as does most of the first 20 to 30 employees, which Rao credits to a collaborative, transparent, debate friendly culture and a real culture interview that can veto otherwise top tier candidates.
    • Dario Amodei holds an open all hands every two weeks, writes a short prepared document, and takes unscripted questions from anyone at the company.
    • AI safety investments in interpretability and alignment have a commercial side effect. Looking inside the model helps Anthropic build better models, and enterprises selling sensitive workloads want to trust the lab they hand customer data to.
    • Anthropic explicitly identifies as America first in its approach to model development, and engages closely with the US administration on capability releases such as Mythos.
    • The longer term product vision is the virtual collaborator: an agent with organizational context, access to the company’s tools, persistent memory, and the ability to work on ideas, not just tasks, over long horizons.
    • CoWork, Anthropic’s extension of the Claude Code paradigm into general knowledge work, is being adopted faster than Claude Code itself when indexed to the same point in its launch curve.
    • Anthropic’s product teams ship daily, with a fleet of agents working across the company on specific tasks. Everyone effectively becomes a manager of agents.
    • The dominant downside risks to Anthropic’s high end forecast are slower customer diffusion of model capability into real workflows, scaling laws flattening unexpectedly, and Anthropic losing its position at the frontier.
    • Rao is most excited about biotech and healthcare outcomes, especially the prospect that AI could push drug discovery and lab throughput up 10x or 100x, turning currently incurable diagnoses into treatable ones within a patient’s lifetime.

    Detailed Summary

    Compute as Lifeblood and the Cone of Uncertainty

    Rao opens with the claim that compute is the most important resource at Anthropic, and the most consequential decision class in the company. You cannot buy a gigawatt of compute next week. You have to anticipate demand a year or two in advance, and the cost of being wrong in either direction is high. Buy too much and the unit economics collapse. Buy too little and you cannot serve customers or stay at the frontier, which are described as the same failure mode. To navigate this, the team uses a cone of uncertainty rather than point estimates. Small differences in weekly growth compound into vastly different two year outcomes, and Anthropic tries to position itself toward the upper end of that cone while preserving optionality. Rao notes he has had to consciously break a lifetime of linear thinking and force himself into exponential models.

    Three Chip Platforms, One Orchestration Layer

    Anthropic uses Amazon’s Trainium, Google’s TPUs, and Nvidia’s GPUs fungibly. That was not free. Adopting TPUs at scale started around the third TPU generation, when outside observers thought it was a strange choice. Anthropic invested years into compilers and orchestration so workloads can flow across chips by generation and by job type. The team works deeply with Annapurna Labs at AWS to influence Trainium roadmaps because Anthropic stresses these chips harder than almost anyone. The result is what Rao believes is the most efficient utilization of compute across any frontier lab, with a dollar of compute going further inside Anthropic than anywhere else.

    Three Buckets and the Model Development Floor

    Compute gets allocated across model development, internal acceleration of employees, and customer serving. The conversations are collaborative rather than zero sum, but there is a hard floor on model development that the company refuses to cross even if it makes customer demand harder to serve in the short term. The thesis is simple. The returns to frontier intelligence are extremely high, especially in enterprise, so cutting model investment to chase near term revenue is a bad trade. Internal employee use is also explicitly protected. Rao notes that diverting that internal usage to external customers would unlock billions of additional revenue today, but the compounding benefit of accelerating researchers and engineers outweighs that.

    Intelligence Is Multi Dimensional

    Rao pushes back hard on the IQ framing of model progress. Benchmarks saturate quickly, and the real signal comes from how customers actually use the models. Anthropic looks at long horizon task completion, tool use, computer use, and time to result on agentic tasks. Two equally capable agents who differ only in speed produce dramatically different value, because the faster one compounds into more attempts and more outcomes. Frontier model leaps are also fuel efficient. The sedan to sports car analogy breaks down because each Opus generation, 4 to 4.5 to 4.6 to 4.7, delivers a step up in capability and a multiplier on per token efficiency.

    From 9 Billion to 30 Billion ARR in One Quarter

    The headline number for the quarter is a leap from about $9 billion of run rate revenue to over $30 billion, accomplished without onboarding a corresponding step up in compute, because new compute lands on ramps locked in 12 months prior. Rao attributes the leap to model capability gains, products that surface that intelligence in usable form factors, and an enterprise customer base that pulls more workloads onto Claude as each generation unlocks new use cases. Coding started the wave with Sonnet 3.5 and 3.6, and the same pattern is now playing out elsewhere in the economy.

    Recursive Self Improvement and Talent Density

    Over 90 percent of Anthropic’s code is now written by Claude Code, including most of Claude Code itself. Rao describes this as a structural reason to keep allocating internal compute to employees even when external demand is hungry. Recursive self improvement is not happening through models that need no humans. It is happening through researchers who set direction and use frontier models to compress months of work into days. Talent density beats talent mass. When Meta and other labs went after Anthropic researchers with very large packages, Anthropic lost two people while peer labs lost dozens.

    Procurement Strategy and the Layer Cake

    Compute lands as a layer cake. Last month Anthropic signed a 5 gigawatt TPU deal with Google and Broadcom starting in 2027, alongside an Amazon Trainium agreement for up to 5 gigawatts. The total is north of $100 billion in commitments. A new tie up with xAI’s Colossus facility in Memphis was announced just before the interview, intended for nearer term capacity to support consumer and prosumer growth. Anthropic evaluates near term and long term compute deals against the same set of variables: price, duration, location, chip type, and how efficiently the team can run it. The relationships are deeper than procurement. The hyperscalers are also distribution channels for the model.

    Platform First, Selective Vertical Bets

    Rao describes Anthropic as a platform first business, with most expected value accruing to customers building on the platform. The team will only go vertical when it can either demonstrate capabilities that are skating to where the puck is going, like Claude Code did before the models could fully support it, or when it wants to set a template for an industry vertical, as with Claude for Financial Services, Claude for Life Sciences, and Claude Security. He acknowledges that surprise capability jumps make customers anxious about the platform competing with them, and frames Anthropic’s mitigation as deeper partnerships, early access programs, and an emphasis on accelerating customer building rather than disintermediating it.

    Pricing, Jevons Paradox, and Return on Compute

    Pricing across Haiku, Sonnet, and Opus has been stable. The notable exception is Opus, which Anthropic deliberately repriced lower when launching Opus 4.5 because Opus class problems were being squeezed into Sonnet workloads. Efficiency gains made it possible to serve Opus profitably at the new level. The consumption response was a classic Jevons paradox, with usage rising far more than the price reduction would have predicted, and Opus 4.6 then slotted in at the same price with a capability bump. Margins are not framed as a per token markup. Compute is fungible across model development, internal acceleration, and customer serving, so Anthropic measures return on the entire compute envelope rather than software style variable cost per call.

    Fundraising, DeepSeek, and Capital Intensity

    Rao joined while Anthropic was closing its Series D, mid frontier model launch and during the FTX share liquidation. Investors initially questioned whether Anthropic needed a frontier model, whether AI safety and a real business could coexist, and why the sales team was so small. The Series E closed the same day the DeepSeek news broke, with markets violently re pricing AI in real time. Since Rao joined, Anthropic has raised over $75 billion, with another $50 billion tied to the Amazon and Google compute deals. The reason for the size of the raises is the cone of uncertainty, not current losses. Returns on compute today are described as robust.

    Mythos, Cyber Capability, and Phased Releases

    The Mythos release marks the first time Anthropic shipped a model under a deliberately phased rollout because of a specific capability spike. Cyber is the dimension that spiked. Where a prior model found 22 vulnerabilities in an open source codebase, Mythos found roughly 250. The defensive applications, automatically patching massive codebases, are genuinely valuable, but the offensive risk is real enough that Anthropic chose to release to a smaller group first and expand access over time. Rao positions this as a template for future capability spikes, not a permanent restriction. He also describes the relationship with the US administration as cooperative, including the Department of War interaction, with Anthropic supporting a regulatory framework that does not strangle innovation but takes responsibility seriously.

    Claude Inside Finance

    Anthropic’s finance team is one of the strongest internal case studies. Statutory financial statements for every legal entity are produced by Claude, with a human reviewer. A skill library of more than 70 finance specific skills underpins a Monthly Financial Review skill that drafts the monthly close at 90 to 95 percent ready, so leadership meetings shift from explaining the numbers to discussing what to do about them. An internal analytics platform called Anthrop Stats compresses weekly insight cycles from hours to 30 minutes. The biggest internal token user in finance is the head of tax, building policy engines, which Rao highlights as evidence that adoption is driven by the most senior people, not just younger engineers.

    Culture, Co Founders, and the Race to the Top

    Seven co founders should not, on paper, work as a leadership group. Rao argues it works because the culture was set early around collaboration, intellectual honesty, transparency, and humility. The culture interview is a real veto, not a checkbox. Dario Amodei runs an all hands every two weeks with a short written piece followed by unscripted questions, and decisions, once made, get clean alignment rather than residual politics. Anthropic frames its approach as a race to the top, where being a model for how to build the technology responsibly is itself a recruiting and retention advantage.

    The Virtual Collaborator and the Frontier Ahead

    The product vision Rao describes is the virtual collaborator. Not just a smarter chatbot, but an agent with organizational context, access to the company’s tools, memory, and the ability to work on ideas over long horizons. Coding was the first domain to feel this, but CoWork, Anthropic’s extension of the Claude Code pattern into general knowledge work, is being adopted faster than Claude Code was at the same age. Product development inside Anthropic already looks different. Teams ship daily, with fleets of agents working across the company, and individual humans increasingly act as managers of those fleets.

    Downside Risks and What Excites Him Most

    The three risks Rao names if asked to do a premortem on a softer year are slower customer diffusion of model capability into real workflows, scaling laws unexpectedly flattening, and Anthropic losing its frontier position to competitors. None of these are observed today, but he is unwilling to claim them with certainty. On the upside, he is most excited about biotech and healthcare. Lab throughput rising 10x or 100x, paired with AI assisted clinical workflows, could turn currently incurable diagnoses into treatable ones within a patient’s lifetime. That is the outcome he wants the technology to chase.

    Thoughts

    The most consequential structural point in this interview is the framing of compute as a single fungible resource pool measured by return on the entire envelope, not as a variable cost per inference call. That accounting shift, if you accept it, breaks most of the bear cases about AI lab unit economics. The bear argument almost always assumes that a token served to a customer is the only thing the chip did that day. Rao’s version is that the same fleet trains models in the morning, runs reinforcement learning at lunch, serves customers in the afternoon, and accelerates internal engineers in the evening. If even half of that is real, the right comparison is total compute spend versus total enterprise value created by the platform, and on that ratio Anthropic looks structurally strong rather than weak.

    The Jevons paradox on Opus pricing is the most actionable insight for anyone running an AI product. Most teams default to either chasing premium pricing on the newest model or undercutting to chase volume. Anthropic did something more disciplined: it left Sonnet and Haiku alone, dropped Opus when efficiency gains made it serveable, and watched aggregate usage rise faster than the price cut. The lesson is that frontier model pricing is not really a price problem. It is a capability access problem, and elasticity around the right tier is much higher than the standard SaaS playbook implies.

    The Mythos cyber jump deserves more attention than it has gotten. Going from 22 to 250 vulnerabilities found in the same codebase is the kind of capability discontinuity that genuinely changes the regulatory calculus. Anthropic is signaling that it can identify these discontinuities ahead of release and choose a deployment shape that respects them. Whether peer labs adopt similar discipline is the open question. Anthropic’s race to the top framing assumes they will be forced to. The competitive market may say otherwise.

    The hiring data point is the most underrated investor signal. Two departures while peer labs lost dozens, during the most aggressive talent war in tech history, is not a culture poster. It is a structural advantage that compounds every time another lab tries to buy its way to the frontier. Money can be matched. Conviction in the mission, transparent leadership, and a culture interview that can veto otherwise stellar candidates cannot. If you believe scaling laws hold, talent retention at this density is one of the few moats that actually scales with capital.

    Finally, the most interesting personal admission is that Krishna Rao, a finance leader trained at Blackstone and Cedar, is openly telling investors that linear thinking is the failure mode he had to break out of. The companies that pattern match this moment to prior technology waves are mispricing it, in both directions. The cone of uncertainty Anthropic uses internally is the right metaphor for everyone else too. If you are forecasting AI as if it is cloud in 2010, you are almost certainly wrong, and the magnitude of the error is much larger than it would be in any prior era.

    Watch the full conversation with Krishna Rao on Invest Like the Best here.