China's artificial intelligence stock rally has hit a wall. According to a Reuters report, as covered by CryptoBriefing, the country's AI bubble has burst, and the damage is already measured in hundreds of billions of dollars.
The STAR50 index, the flagship gauge of Shanghai's tech-focused STAR Market, tracks China's leading AI and semiconductor companies. It has dropped nearly 40% from its July peak. That slide has wiped out approximately $480 billion in market value in less than four months.

How Bad Is the Damage

The sell-off is not confined to speculative technology names. China's CSI 300 index, the benchmark for blue-chip stocks, is down roughly 20% from its June highs.

Some of the most heavily hyped individual names have fared worse. Unitree, the humanoid robot maker, has seen its shares halve since the company listed in August. CXMT, a memory chip maker, has fallen more than 25% in the past month alone, while AI chip designer MetaX Integrated Circuits and GPU developer Moore Threads have both seen their share prices roughly cut in half since July 2026.

Why This Selloff Hit Harder

The sheer scale of AI's footprint in Chinese markets explains why the fallout spread so widely. According to Goldman Sachs, AI-related stocks accounted for 42% of the total market capitalization of China's stock market, while the same group made up 57% of turnover across A-shares and H-shares, the mainland-listed and Hong Kong-listed shares of Chinese companies. In other words, more than half of all trading activity was chasing a single theme.

Fund manager Dong Baozhen described the earlier run-up bluntly, calling it a "speculative crazy bull," and framed the steep losses as a turning point for retail investors, who had piled heavily into the segment.

No single trigger has been identified for the reversal. Factors flagged in the coverage include stretched valuations, looming tax obligations, and rising risks tied to export controls, the government restrictions governing cross-border trade in advanced technology.

Regulators Saw It Coming, Sort Of

Chinese regulators were not entirely caught off guard. On October 9, 2026, months after the STAR50 peaked in July, China issued new guidelines meant to prevent investment bubbles in what it calls "new productive forces," a category that includes AI.

The episode also threatens a broader policy goal. Chinese authorities have been working to encourage households to put more of their savings into the stock market.

A Tale of Two AI Trades

The contrast with the United States is striking. While China's AI stocks have been in freefall, the Nasdaq has seen a comparatively modest pullback of 6%. Concentration, retail-heavy participation, and export-control exposure appear to have amplified the damage in China.

What Comes Next

The new anti-bubble guidelines are worth watching closely, and export controls remain the other major variable. Any formal restrictions on Chinese AI equipment exports could hit company revenues directly, giving fundamental weight to what has so far been a sentiment-driven sell-off.

When a single sector accounts for 42% of market value and 57% of turnover, the trade is crowded by definition, and crowded exits rarely go smoothly.