The broad unwind of AI-linked positions was triggered by growing concern that massive AI infrastructure spending may not be sustainable . Chinese chip and AI stocks were hit particularly hard. The STAR 50 fell 30% from its early-July peak of 2,255.25 to 1,588.4 by late July
. On a single day in mid-July, the chip-heavy gauge plunged as much as 8%, extending its drop from a June high to 21%
. The CSI Semiconductor Index retreated from an all-time peak, plunging 9.4% in its biggest one-day decline in nearly four years
.
The Hang Seng Index's price-to-earnings ratio of 12.2 made it a standout bargain globally . In contrast, the STAR 50 had surged on AI hype earlier in the year, leaving it vulnerable to multiple compression when sentiment turned. Mainland investors saw Hong Kong stocks as a "value haven" relative to the frothy valuations on the STAR Board
.
Even the Hang Seng Tech Index, which includes many of the same companies that trade on the mainland, was cheap by historical standards. As of July 20, it traded at a trailing P/E of about 22.6 times, roughly 38% of its own historical peak valuation .
According to Industrial Securities, "southbound" (mainland) capital was the primary driver of increased Hong Kong equity positions in early July . From July 1 through August 5, southbound net inflows reached HK$75.1 billion, while foreign capital began returning significantly from mid-July onward, contributing another HK$6.9 billion
.
Total July purchases via Stock Connect reached HK$62.9 billion (approx. US$8 billion), more than doubling the HK$27.1 billion bought in June . On single days, net inflows exceeded HK$20 billion — notably HK$20.5 billion on July 6 and HK$13.4 billion on July 15
.
The buying was heavily concentrated in large-cap, cash-flow-generating Hong Kong-listed names that offered earnings visibility — exactly the kind of stocks that look attractive when AI-growth narratives are under pressure. On July 15, a heavy-volume day, southbound capital bought:
For the week ending July 10, southbound net buying hit HK$39.06 billion — the highest weekly net inflow since April — with Zhipu AI receiving the largest single-stock inflow at HK$13.7 billion . Alibaba, Tencent, and Meituan again featured prominently
.
Ironically, the Hang Seng Index had already fallen 10.7% in the first half of 2026, reflecting weak consumption sentiment and the fact that Hong Kong participated little in the AI rally that boosted other markets . This prior underperformance meant the HSI had less inflated AI exposure to shed when the global selloff hit, making it a more defensive landing spot for rotating capital
.
Beijing dispatched the "national team" over the weekend of July 18-20, with two major state-owned funds announcing nearly 60 billion yuan (US$9 billion) in share purchases to stabilize the mainland tech selloff . The ChinaAMC STAR 50 ETF saw record inflows of 13.8 billion yuan, signaling strong state-backed buying
. These actions underscored how severe the mainland AI-stock distress had become, further incentivizing mainland investors to diversify into Hong Kong
.
The net effect was a classic flight-to-value rotation. Mainland investors dumped expensive, AI-exposed mainland tech stocks that had soared and then crashed, and redeployed capital into Hong Kong-listed blue chips at a 12.2× P/E — a market that had already repriced lower and carried far less AI-premium risk . The move was so pronounced that by early August, the Hang Seng Index had risen 13.1% for the year to date, while the STAR 50 remained in record slump territory
.