A quiet threat is closing in on China’s open-source AI

This is an opinion piece.

For a few days in June, the argument for open-source AI models seemed to write itself.

Just days after Anthropic launched Fable 5, the public-facing version of its more powerful Mythos-class models, the US government moved to suspend it due to national security concerns. Anthropic responded by disabling access to both Fable 5 and Mythos 5.

Access to both models has since been restored, but the episode still exposed the problem of depending on closed APIs.

For open-source advocates, this was the clearest illustration yet of their core argument: a single government directive was enough to cut off access for millions of users overnight.

To be fair, governments restrict foreign digital services all the time. When TikTok faced a US ban, users found alternatives within days.

But social media platforms are interchangeable in a way that frontier AI models are not. A business built around one frontier model can’t simply swap in another. These models are different enough that replacing one can break the product or significantly degrade its performance.

At least one US company experienced this and decided to sue the US government, arguing that the directive caused immediate and severe harm to its business.

Online chatter has pointed to how this benefits Chinese AI labs, who have mostly relied on open-source releases for better distribution but have trailed US firms in terms of model capabilities. The restriction gives Chinese companies a strong narrative centered around accessibility being the most important feature.

Z.ai is a clear example. The Beijing-based lab released its latest model, GLM-5.2, for its paid subscribers just one day after the Fable 5 suspension, leaning heavily into that exact narrative.

Moving forward, it’s tempting to conclude that Chinese AI labs will simply double down on open-weight models. DeepSeek, for example, remains committed to its open-source strategy, The Information reported.

But the situation isn’t that clear cut. The distribution strategies of Chinese AI labs will have less to do with whether US models will become more restrictive. Instead, it will be about how they respond to competition from an unlikely source: their own inference providers.

Victim of its own distribution?

Going open-source has proven to be an effective customer acquisition strategy for Chinese AI firms so far. OpenRouter, a platform that lets developers compare and access AI models from different providers, gives us an indication of this.

A price war over someone else’s model

The game theory of staying open