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- Anthropic Revokes OpenAI's Access to Claude 😱
Anthropic Revokes OpenAI's Access to Claude 😱
Demis Hassabis: Future of AI, Simulating Reality, Physics and Video Games

Welcome to another edition of Horizon AI,
Anthropic has terminated OpenAI's API access to its Claude AI models, alleging violations of terms of service.
Let’s jump right in!
Read Time: 4.5’ min
Here's what's new today in the Horizon AI
Chart of the week: The World’s 20 Most Powerful AI Supercomputers
Anthropic Cuts Off OpenAI's Access to Claude
Free Resources
AI tools to check out
Video of the week
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Chart of the week
The World’s 20 Most Powerful AI Supercomputers

This graphic highlights the world’s top compute clusters, according to data from Epoch AI.
xAI’s Colossus Memphis Phase 2 leads the list with 200,000 H100 equivalents—double the size of the second-largest cluster.
AI News
ANTHROPIC
Anthropic Cuts Off OpenAI's Access to Claude

OpenAI was just informed that its access to the Claude API has been cut off due to an alleged violation of Anthropic’s terms of service.
Details:
The company justified the move by stating that OpenAI was “using our coding tools ahead of the launch of GPT-5.”
OpenAI had reportedly been plugging Claude into its own internal tools using special developer access (APIs), which allowed the company to run tests to evaluate Claude’s capabilities in things like coding, creative writing, and safety against its own AI models.
Anthropic’s commercial terms of service state that customers are prohibited from using the service to “build a competing product or service, including to train competing AI models,” or to “reverse engineer or duplicate” the services.
An OpenAI spokesperson responded by describing its usage as “industry standard” and added: “While we respect Anthropic’s decision to cut off our API access, it’s disappointing considering our API remains available to them.”
OpenAI is preparing to release GPT-5 this month, after multiple delays. The model is rumored to be significantly better at coding tasks, an area where Claude also excels.
AI Findings/Resources
👀 Meta AI model can reproduce almost half of Harry Potter book
✅ 3 ways to use the new ChatGPT Study mode that aren’t for homework
AI Tools to check out
📈 Trendtracker: Discover trends that matter instantly.
💬 Concierge: Talk to your apps with natural language.
📊 Basejump: AI data analytics platform.
✅ AutoDiagram: Transform ideas into professional diagrams with AI.
💤 Remy AI: Sleep & health coach.
Video of the week
Demis Hassabis: Future of AI, Simulating Reality, Physics and Video Games
Lex Fridman and Demis Hassabis discuss various AI-related topics, including whether AI can truly "understand" the world, the race for AGI and Google’s chances of emerging as a “winner,” what makes humans special in the face of increasingly intelligent AI, among other things.
Here are some timestamps (more can be found in the pinned comment):
14:26 - Veo 3 and understanding reality
52:15 - Path to AGI
1:03:01 - Scaling laws
1:17:54 - Google and the race to AGI
1:42:27 - Future of programming
2:02:50 - Humanity
That’s a wrap!
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Gina 👩🏻💻