The long (open) weight is over

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Jensen Huang joins X to defend open weight AI: The Nvidia founder’s first-ever post shared an open letter to Congress titled “Open Weights and American AI Leadership.” Signatories include more than 20 major tech companies, including Nvidia, Meta, Microsoft, Palantir, IBM, and ServiceNow (though OpenAI and Anthropic were notably absent). The letter argues that betting the US AI market on a handful of closed models is riskier, not safer, creating a single point of failure that’s difficult to test or defend. Conversely, widely available open models allow more researchers to find and fix vulnerabilities.
Stripe in talks to buy OpenRouter for close to $10B: OpenRouter gives developers one interface to manage hundreds of AI models — including offerings from OpenAI, Anthropic, and open weight labs — allowing for easy comparisons and switch-offs. Stripe already handles OpenRouter’s payments and billing. Buying the company simply pushes them into owning the layer that developers use to access and pay for models. The headline here is the price: OpenRouter was valued at $1.3 billion in May, so a $10 billion deal bumps that up by 8x in a matter of months. Talks could still fall apart, but it’s becoming clear how much value investors have attached to the plumbing behind the AI model marketplace.
Anthropic adds Opus and Sonnet to voice mode: Once limited only to the lighter and cheaper Haiku series, the AI giant upgraded voice mode to run on more capable models. Users can even switch mid-conversation, depending on whether they require speed or deeper reasoning. This also marks a shift toward making voice mode more agentic, opening up connected tools like Gmail, Slack, and Calendar, and enabling real-world actions like sending an email or rescheduling a meeting, rather than just walking through the planning stages. Anthropic also added support for 10 additional languages, all switchable mid-conversation. The update rolls out in beta across mobile, desktop, and the web this week. (The lab also dropped Opus 5 as we were proofing this very newsletter.)

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OpenAI will roll out ChatGPT Health to all US users 18 and older across every plan, including the free tier, and they’re integrating the product more seamlessly into the overall ChatGPT experience.

The feature launched as a testing hub back in January, allowing users to connect their data from Apple Health, Function, and MyFitnessPal, along with medical records from Epic, Oracle Health, and One Medical. According to the AI giant, weekly, health-related queries on ChatGPT have grown from 230 million to 300 million since the feature’s launch. The company is also broadening the program’s scope, as roughly 70% of health-related queries were still happening outside of the dedicated hub. Users can now pull their connected health data into any session on ChatGPT, not just in the Health product.

The company marked the occasion by boasting about improvements to their health-related models. They note that even their smallest new model bests last year’s flagship on internal benchmarks.

Still, there are headwinds here. Chief rivals Anthropic launched their own Claude for Healthcare product back in January. More generally, skepticism abounds among the public and experts about the use of chatbots for health-related queries specifically. Independent studies still find chatbots unreliable when dispensing medical advice.

It’s not even a friendly news cycle for OpenAI specifically on this front. Also this week, a Florida pastor filed suit against the company, after ChatGPT dissuaded him from seeking medical advice regarding what turned out to be an impending, genuine health crisis. – Zach and Lon

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This Week in Startups

E2315: In the first episode of our week-long summer trip to Tokyo, Jason is joined by CEO Bilal Kharouni of Ekei Labs. He’s using AI and epigenetics to develop longevity treatments in Okinawa, one of the world’s legendary Blue Zones noted for its residents’ tendency to live long, healthy lives. He discusses why a smaller raise can go much further in Japan than Silicon Valley, why the best moat for biotech companies is not an AI model but their data, and why Ekei killed a burgeoning side business in order to maintain focus.

E2314: Ent founder Brandon Dixon joins the pod to explain why the traditional cybersecurity process — which cleans up a system after a breach has occurred — is backwards. He’s designed an AI agent that lives on everyone’s corporate laptop, and keeps an eye out for risky clicks and potential leaks before they cause a problem. PLUS Clawra creator David Im returns to the show with Sume’s Avatar, a multi-model orchestration layer that he claims can one-shot your AI generated videos without the endless slot machine-style trial and error.

E2313: Science fiction is full of surgery-bots, and Andromeda Surgical is hoping to bring this dream into reality (preferably in a less troubling way than that one scene in “Prometheus.”) CEO Nick Damiano stops by the show to explain why the company is focusing on software, and relying on off-the-shelf robot arms from Germany to actually complete the procedures. Plus Mogul co-founder/CEO Alex Blackwood shows Jason how his platform allows anyone to buy fractional shares of rental homes for as low as $250, benefitting from monthly dividends and appreciation without having to become a landlord.

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