Kimi K3 smashes open-source ceiling, global tech stocks lose $470B in 3 days

Moonshot AI's Kimi K3 open-weight large language model has triggered a dramatic selloff in global tech stocks, with approximately $470 billion in market value wiped out over three days, according to a report from 21st Century Business Herald. The figure reflects market expectations that open-source AI is now capable of reshaping the competitive landscape.

Kimi K3 has demonstrated performance approaching frontier closed-source models such as Anthropic's Fable 5, particularly in security vulnerability detection and code repair tasks. A developer reported that Kimi K3 successfully fixed 15 critical security bugs — tasks that OpenAI and Anthropic's models had refused to perform due to their cyber guardrails.

The model costs roughly one-third the price of Fable 5 for inference, giving it a significant cost advantage alongside competitive capabilities. White House AI and crypto advisor David Sacks posted on X that closed-source labs are trying to convince the government to eliminate their open source competition, noting that Chinese models handle tasks American models refuse without issue.

The situation has intensified policy tensions in Washington. The Trump administration is reportedly considering banning U.S. companies from using Chinese open models, and the Commerce Department previously contemplated adding multiple Chinese AI labs to the Entity List. Chinese President Xi Jinping called for global cooperation at WAIC, opposing the overstretching of the concept of national security in AI. Kimi K3's breakthrough marks a turning point where open-source AI has become a force capable of moving global markets.