OpenAI rips Anthropic, distances itself from Microsoft

https://www.axios.com/2026/04/09/openai-100-billion-in-ad-revenue" target="_blank">OpenAI is tightening its ties with Amazon, saying its early investor and partner https://www.axios.com/2025/10/29/microsoft-openai-azure-deal-agi" target="_blank">Microsoft was holding it back.

Why it matters: The ChatGPT creator is under pressure to keep pace with its competitors as the AI economy evolves and https://www.axios.com/2026/04/03/anthropic-openai-ipo" target="_blank">its potential IPO approaches.

Driving the news: OpenAI's recently established cloud partnership with Amazon Web Services has generated "frankly staggering" demand from enterprise customers, OpenAI's new revenue chief, Denise Dresser, said in an internal memo.

• "We are firing on all cylinders to establish this as a scaled distribution channel," Dresser said.

Friction point: Dresser wrote that OpenAI's Microsoft partnership has been "foundational to our success" but "has also limited our ability to meet enterprises where they are," which, "for many," is Amazon's less-restrictive Bedrock platform.

• Bedrock provides clients access to all major AI models.
• The pivot to Amazon enables OpenAI to develop "systems that can operate reliably over time and across complex business processes," she added.
• The move comes after Amazon recently https://www.axios.com/2026/02/27/openai-funding-nvidia-amazon" target="_blank">announced a $50 billion investment in OpenAI and a deal to become the exclusive third-party cloud distribution provider for https://www.axios.com/2026/02/05/openai-platform-ai-agents" target="_blank">OpenAI Frontier, its new agent-management platform.

Behind the scenes: Tension between Microsoft and OpenAI has been palpable.

• Microsoft, which declined to comment for this story, started https://techcrunch.com/2024/08/01/microsoft-now-lists-openai-as-a-competitor-in-ai-and-search/" target="_blank">describing OpenAI as a competitor in 2024.

In the Sunday memo, Dresser also ripped OpenAI rival https://www.axios.com/2026/04/13/anthropic-revenue-growth-ai" target="_blank">Anthropic, saying the Claude creator is constructing a narrative "on fear, restriction, and the idea that a small group of elites should control AI."

• Anthropic CEO Dario Amodei has repeatedly aired public warnings about the technology's https://www.axios.com/2025/05/28/ai-jobs-white-collar-unemployment-anthropic" target="_blank">dangers.
• "Our positive message will win over time: build powerful systems, put in the right safeguards, expand access, and help people do more," Dresser said.

She also accused Anthropic of an "inflated" run rate, using accounting methods to make its "revenue look bigger than it is."

• Anthropic had no immediate comment.

The bottom line: AI's biggest alliances are shifting.