A decade-long personal feud has been shaping the entire industry in the world of AI. A new report by The Wall Street Journal has revealed deep disagreements between the founders of Anthropic and OpenAI.

The story begins in 2016 when Dario Amodei, his sister Daniela, and Greg Brockman of OpenAI had a debate in a shared apartment in San Francisco about how to develop AI. Brockman believed that everyone should be informed, while Dario favored informing the government first. This small disagreement later became a defining factor for the direction of both companies.

In mid-2016, Dario joined OpenAI, but tensions over power and recognition grew during the four years he worked there. In 2017, there were major layoffs at Elon Musk’s request, which Dario considered brutal. When Sam Altman took over in 2018, new problems emerged. Dario felt that his contributions were being undervalued, especially when his role in developing GPT-2 and GPT-3 was overlooked.

The tension peaked when Altman accused the Amodei siblings of encouraging colleagues to give negative feedback. By the end of 2020, Dario’s team had decided to leave OpenAI. In his separatist memo, Dario divided AI companies into two categories—75 percent for public interest and 25 percent market-based.

A few weeks later, Dario, Daniela, and about a dozen employees founded Anthropic. Today, five years later, the combined valuation of both companies exceeds $3 trillion. Recently, in a group photo at an AI summit in New Delhi, Dario and Altman kept their distance from each other — a scene that tells the whole story.

Internally, Dario’s language has become quite intense. He described the Altman-Musk dispute as a fight between Hitler and Stalin, compared OpenAI to tobacco companies, and said that given Altman’s behavioral patterns, everything he hears makes sense. For Anthropic, all this has become a branding strategy — presenting itself as a healthier alternative.

This is not just a corporate dispute. It’s a decade-old personal grudge that is shaping the future of AI.