Sitemap – Japan Stock Alpha

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Home Overview of Japanese stock themes, key statistics, and featured research articles.
Japan Stock Alpha Portfolio Hypothetical ¥10M portfolio across 10 Japanese stocks with live price tracking.
Sitemap This page — a full index of all content on the site.
About What Japan Stock Alpha is, why it exists, and what we cover.

Company Deep Dives

Berkshire Mitsubishi Corp.: one stock, a world of business Full deep dive into Mitsubishi Corporation (8058.T) — LNG Canada, DCF valuation, FY2026/3 results, and downloadable Excel model.
Berkshire Marubeni Corporation: the quiet one that just hit ¥10 trillion Deep dive into Marubeni (8002.T) — Strategic Platform Businesses, FY2026/3 earnings, capital allocation under CEO Omoto, and downloadable valuation model.
Berkshire Mitsui & Co.: the iron ore and LNG one Deep dive into Mitsui & Co. (8031.T) — iron ore, LNG and copper, the MTMP2029 plan and ¥1.4T 2030 profit vision, with a downloadable valuation model.
Berkshire Itochu Corporation: the consumer-focused one Deep dive into Itochu (8001.T) — the consumer-focused trading house behind FamilyMart. Record profits, hands-on management, and downloadable valuation model.
Berkshire Sumitomo Corporation: portfolio in motion Deep dive into Sumitomo Corporation (8053.T) — SCSK Digital AI, Sumisho Air Lease, asset replacement, the post-investment free-cash-flow test, and a downloadable valuation model.

Opinion & Deep-Dive Articles

US × AI Is the AI market a bubble? Why “this time is different” is only half true A data-driven opinion piece on the US AI boom — real earnings against bubble-like valuation, concentration and capex risk, compared with the dot-com bubble, Nifty Fifty and Japan 1989. 9 min read.
Berkshire What Berkshire bought in Japan — and why it worked How Warren Buffett's 2020 bet on five Japanese trading houses became one of Berkshire's best international investments. 8 min read.
Semis & AI Japan's AI boom: equipment, memory, and materials behind every fab The Japanese chip equipment makers, memory suppliers, and materials specialists powering the global AI infrastructure buildout. 8 min read.
Defense Japan's defense buildup: the biggest shift since WWII Japan is doubling defense spending to 2% of GDP by 2027 — the listed contractors building fighters, submarines, and missiles. 7 min read.
Rare Earths Minamitorishima: rare earths under Japan's seabed A remote island atop one of the world's largest rare earth deposits, with test mining starting in 2026. 6 min read.

Research Themes

Overview Key statistics, index comparisons, and the big investment idea behind Japanese equities.
Berkshire & Trading Houses Mitsubishi, Mitsui, Itochu, Marubeni, Sumitomo, and Tokio Marine — the sōgō shōsha thesis.
Semiconductors & AI Tokyo Electron, Advantest, Shin-Etsu, Sony, Denso, Disco, Lasertec, Ibiden, and Kioxia.
Defense Mitsubishi Heavy Industries, IHI Corporation, and Kawasaki Heavy Industries.
Rare Earths Toyo Engineering, JAPEX, MODEC, Furukawa, Toa, IDEA Consultants, and Pacific Metals.
Macro Nikkei vs S&P 500 performance, USD/JPY trends, and P/E ratio comparisons.

Technical