Six Historical Rules of A-Shares Have Broken Down — AI Remains the Core Theme in H2

Claire Weston
Published todayAbout 18 min read

GF Securities' strategy team finds that six long-standing A-share rules validated over two decades have all failed in this cycle, driven by the end of the property super-cycle and the peaking of demographic dividends — the earnings gap between AI and non-AI sectors is likely to widen further in H2, leaving little fundamental support for a style rotation.

01

Which six "iron rules" have broken?

A-shares had never re-rated for three consecutive years — but 2024–2026 marks the third straight year of valuation expansion. Electronics and telecom have led the market into a fourth year, breaking the rule that sectors rarely outperform for more than three.
Institutional holdings in electronics have exceeded 20% for over five quarters, yet the sector keeps rallying — historically, hitting 20% was almost a reliable top signal.
Telecom was the most heavily added sector for four consecutive quarters; subsequent excess returns were +31%, +14%, +10%, +37% — destroying the old rule that "the most aggressively bought sector always underperforms next quarter."
TMT turnover share has breached 45%, above the prior assumed ceiling of 40%. Meanwhile, finished-goods inventory bottomed in June 2023, yet three years later no large-scale fiscal stimulus has materialized. This means → after the property cycle's exit and the demographic peak, A-share profit and market-cap structures have fundamentally shifted, rendering the old playbook obsolete.
02

Which rules are approaching a tipping point?

As of June 24, the top-5% stocks' share of turnover (20-day moving average) reached 49.8%, closing in on the 2015 and 2021 historical highs. In plain terms = market money is concentrating into fewer and fewer names, nearing an extreme.
Drawing on the U.S. dot-com cycle, GF argues this ceiling could be breached — if it is, the trend of "a handful of stocks absorbing most liquidity" can run further.
Sector valuation dispersion — measured by the standard deviation of industry PB historical percentiles — has hit an all-time high. But GF reviewed six prior episodes of extreme dispersion and concluded: peak valuation divergence does not equal a bull-market top.
03

What is the K-shaped split, and will it close in H2?

H1 A-share pricing showed a clear K-shape: companies in the top 10% by revenue growth averaged over 40% gains year-to-date, while stocks with strong cash flow, high dividends, and low valuations actually fell harder. This reflects the global economy's own K-shaped divergence — regions with AI supply-chain assets are booming; those without are weakening.
The upper arm: the global top-five cloud companies plan $769 billion in 2026 capex, revised up again from the start of the year. H100 rental prices topped $2.80/hour. Doubao's daily token calls broke 180 trillion in June; Google's monthly token consumption approached 3,000 trillion.
The lower arm: China's fiscal stance remains restrained, cushioned by resilient external demand. This means → whether domestic policy truly ramps up in H2 hinges on whether the overseas restocking impulse fades. Bank net interest margins have dropped to a record low of 1.40%, making a broad rate cut unlikely. Fiscal spending ran at −0.3% YoY through January–May; Q3 may see modest backfilling, but the bias stays cautious.
04

Where is the money coming from — and going — in H2?

H1 saw roughly ¥860 billion in net retail inflows, up from about ¥690 billion in H2 2025. But H2 faces headwinds: margin-trading momentum is slowing, northbound flows are capped by U.S. Treasury yields, industrial shareholders are accelerating sales around a lock-up expiry peak, and mega-IPOs such as CXMT are expected to divert funds. The net supply-demand gap is projected to narrow by over ¥100 billion.
Retail still has room: demand-deposit deviation from trend is about ¥1 trillion short of prior "great migration" peaks. The share of active equity funds back to breakeven has reached 50.8%, significantly easing redemption pressure.
Institutions are taking profits: active equity-mix fund positions have dropped to 85.7%, and active private-fund positions have slipped to 62.3%. Insurance capital is the key stabilizer — Q1 2026 insurance inflows hit the highest level since 2013, and further incremental buying is expected in H2. In plain terms = retail investors still have cash to move in, but institutions are selling — the market is shifting from an inflow-driven phase to a turnover-driven one.
05

Beyond AI, which sectors have fundamental support?

Energy-storage lithium batteries are seen as the most certain non-AI sector reaching a recovery inflection: China's June lithium-cell production schedule hit roughly 268 GWh, a record high for the fourth consecutive month. A recent pullback in lithium-carbonate prices eases pressure on storage-project IRR — the internal rate of return that determines whether a project is profitable.
Non-ferrous metals: gold's structural thesis is intact — rising global sovereign debt, a weakening dollar reserve status, and central-bank buying. Copper's supply-demand gap is even more structural: global copper output turned negative YoY starting March 2026.
Innovative-pharma leaders trade below their mean minus one standard deviation, but need two triggers to re-rate: easing U.S.–Iran tensions and a leg down in U.S. Treasury yields. This means → these sectors have fundamental floors, but timing depends on external variables — not on rotational flows out of AI.
06

What is the single most important takeaway for H2?

GF emphasizes that amid all the broken rules, one first principle still holds: "relative earnings advantage determines relative stock-price performance."
AI-sector EPS keeps getting revised upward; non-AI earnings show no sign of accelerating — the earnings-growth gap between AI and non-AI will most likely continue widening in H2.
In plain terms = for other sectors to see a genuine broadening of gains, their own fundamental inflection must actually arrive — it won't come from money "spilling over" from AI. Until that inflection materializes, the AI theme's relative edge is hard to shake.

Content is for reference only, not financial advice.

Six Historical Rules of A-Shares Have Broken Down — AI Remains the Core Theme in H2 · nashnova