Anthropic CEO Calls for AI Development Slowdown, OpenAI CEO Supports

On 13 September 2026, Anthropic CEO Dario Amodei published an essay on X calling for a slowdown in AI development.2 Amodei outlined a three‑step plan: independent evaluators, industry coordination, and international cooperation.2 He warned that AI could, within six to twelve months, lead a swarm of agents that could take over the internet.3

Amodei’s call was echoed by OpenAI CEO Sam Altman, who said he agreed with the sentiment.1 Altman also said OpenAI would not file for an IPO in 2026, citing safety concerns.1,7,9 Elon Musk, CEO of xAI, and Demis Hassabis of DeepMind also publicly supported Amodei’s proposal.2,5,6

The U.S. President Donald Trump dismissed the warnings, saying the U.S. should stay ahead of China in AI.6,10,11,13 Trump said “negative forces” were exaggerating AI risks.10,13 Some U.S. lawmakers urged new rules to govern AI systems after warnings from Anthropic researchers.1

SoftBank shares fell 13% after the CEOs called for a slowdown.12 The calls for caution were part of a week of warnings from AI researchers.8 Amodei’s essay was shared widely on social media, prompting discussion among tech leaders.2,4

Altman said the decision not to go public was due to the need to address safety and alignment.1 The slowdown proposal includes embedding independent evaluators with employee‑like access to verify safety practices.2 The proposal also calls for coordination among frontier AI firms to set safety standards.2