‘Summer storm‘ in stock selection: drivers and countermeasures

Research evidence excerpt

‘Summer storm‘ in stock selection: drivers and countermeasures

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Japan Equity Strategy

“Summer storm” in stock selection: drivers

and countermeasures

Investment Strategy

09 July 2026

Rotation in stock selection: (1) AI investment concerns and Investment Strategy

(2) changes in the macro environment Japan

AI-related stocks were hit by heavy selling, creating a “summer storm” in stock selection. Masashi Akutsu >>

Strategist

At the same time, investment capital spread into other sectors. Index moves remained BofAS Japan

relatively moderate, masking intense underlying shifts. We view these developments as +81 3 6225 7754

masashi.akutsu@bofa.com

consistent with our long-held view (see our 29 June Japan Insight report and others).

Tetsuhiro Tokuyama >>

However, President Trump has indicated an end to the ceasefire with Iran. We believe Strategist

the broad market framework remains unchanged for now, but a sustained spike in crude BofAS Japan +81 3 6225 8499

oil prices would be a major risk. tetsuhiro.tokuyama@bofa.com

What drove the sell-off in AI-related stocks? We believe several factors were at work.

The first was vague concern about the sustainability and profitability of accelerating

data center investment. For example, (1) expansion in data center investment drove up

memory prices, forcing Apple and Microsoft, which were supposed to be key investors,

to raise prices; (2) AI token usage costs rose; and (3) while use of Anthropic products

was suspended, demand shifted toward low-cost Chinese open AI models.

We found no decisive negative development regarding data center investment, and other

factors likely contributed to the decline in AI-related stocks. We believe one was the

change in the macro environment.