Nuclear Hidden Gems — FINAL

Report Date: 2026-04-11 | Holdings: 9 | Theme: nuclear_energy | Top-3: 50.0% | HHI: 0.1276 (~7.8 effective names)

Portfolio with 9 holdings (4 HIGH conviction). Theme: Nuclear / Energy. Nuclear restart and energy transition value chain 2 holding(s) have negative FCF — flagged below.
FCF Alert: 2 holding(s) have negative free cash flow: 7004.T (KANADEVIA CORPORATION, ¥-3B, 10.0% weight), 5310.T (TOYO TANSO CO LTD, ¥-10B, 7.0% weight)— review at next earnings

2. Macro Context

Nuclear / Energy: Nuclear restart and energy transition value chain


3. Comparison Table

Fundamentals from yfinance. Forward PE must be verified against StockAnalysis.com for Japanese mid/small-caps (known yfinance data quality issue).

StockTickerWtConv PEFwd PEP/BROEOpMD/EDYFCF
YOKOGAWA ELECTRIC CORP 6841.T 18.0% HIGH 25.5 26.1 2.84 12.2% 14.1% 5% 1.4%
JAPAN STEEL WORKS 5631.T 17.0% HIGH 30.4 32.7 3.29 10.5% 8.1% 34% 0.9%
FUJI ELECTRIC CO. LTD. 6504.T 15.0% HIGH 18.8 17.7 2.11 11.8% 10.0% 13% 1.6%
ORGANO CORP 6368.T 10.0% HIGH 24.0 31.8 5.07 23.5% 19.4% 24% 1.3%
KANADEVIA CORPORATION 7004.T 10.0% MED 10.2 8.0 1.02 5.8% 2.0% 88% 2.3% ¥-3B
SUMITOMO HEAVY INDUSTRIES 6302.T 10.0% MED 19.2 14.8 0.87 4.7% 5.3% 37% 2.9% +¥14B
KURITA WATER INDUSTRIES 6370.T 8.0% MED 37.1 22.6 2.37 6.8% 14.6% 32% 1.4% +¥31B
TOYO TANSO CO LTD 5310.T 7.0% LOW 20.6 11.7 1.16 5.7% 11.0% 6% 2.7% ¥-10B
NIPPON CARBON CO 5302.T 5.0% LOW 10.6 10.3 0.95 8.7% 14.3% 16% 4.3% +¥0B

4. Stock-by-Stock: Why This Stock, Why This Weight

6841.T — YOKOGAWA ELECTRIC CORP — 18.0% HIGH SMR / Construction

WHY this stock: Signed strategic agreement with Rolls-Royce SMR (Feb 2, 2026) to deliver DPCS for the entire SMR fleet — UK + Czech Republic. Exclusive contract. 65+ years nuclear monitoring pedigree. Also: Saudi Aramco CPA since 2012 (AI agents Oct 2025), Shell robotics JV (Jun 2025), ADNOC $708M framework.

WHY 18.0%: Best quality-to-valuation ratio. ROE 12.2%, op margin 14.6%, D/E only 0.05. FCF strongly positive at ¥88B — highest in portfolio. Both Claude and GPT rated 'agree; keep.'

What could go wrong: Rolls-Royce SMR program delays or cancellation; oil/gas capex downturn affecting core business.

Monitoring trigger: If Rolls-Royce SMR project milestones slip, reassess nuclear optionality premium. Watch May earnings for SMR revenue recognition timing.

25.5x
PE
26.1x
Fwd PE
12.2%
ROE
14.1%
Op Margin
5%
D/E
1.4%
Yield

5631.T — JAPAN STEEL WORKS — 17.0% HIGH SMR / Construction

WHY this stock: 80% global monopoly in nuclear reactor pressure vessel forgings. Only company capable of making largest single-piece nuclear forgings. Backlog >¥135B. METI officially named JSW as BWRX-300 supplier (Mar 2026). ¥28B CAPEX committed for SMR production upgrades. 18-month manufacturing cycle = multi-year visibility.

WHY 17.0%: Monopoly is irreplaceable but reduced from 25% due to negative operating CF (-¥4.6B) and FCF (-¥19.7B) in FY2025 driven by ¥32.3B inventory build for SMR capex program.

What could go wrong: SMR order pipeline doesn't convert to revenue; cash burn continues longer than expected; competitor emerges for smaller forgings.

Monitoring trigger: If operating CF remains negative in FY2026 results (May 2026), reduce to 12%. If inventory converts to revenue (OCF turns positive), increase back to 20%.

30.4x
PE
32.7x
Fwd PE
10.5%
ROE
8.1%
Op Margin
34%
D/E
0.9%
Yield

6504.T — FUJI ELECTRIC CO. LTD. — 15.0% HIGH Nuclear Operations

WHY this stock: Top-5 global in nuclear radiation monitoring (65+ years, 95% domestic market share) AND top-5 global in IGBT/SiC power semiconductors for EVs. Confirmed customers: Honda (IGBT), Bosch (SiC JV), Vestas (wind), JNFL Rokkasho (300-channel panel). Raised FY operating profit guidance to ¥128.5B.

WHY 15.0%: Dual-theme (nuclear + EV) at PE 18.6x with ROE 11.8%, D/E 0.13, FCF +¥51B. Both Claude and GPT independently said 'agree; keep' in BOTH portfolios.

What could go wrong: Industrial capex downturn; SiC competitors erode IGBT share faster than expected.

Monitoring trigger: Watch May earnings for nuclear instrumentation order flow and power semi backlog. If either segment weakens, reassess dual-theme premium.

18.8x
PE
17.7x
Fwd PE
11.8%
ROE
10.0%
Op Margin
13%
D/E
1.6%
Yield

6368.T — ORGANO CORP — 10.0% HIGH Nuclear Operations

WHY this stock: Nuclear water purification specialist — condensate filters, demineralizers, reactor water cleanup for every operating reactor. Best quality: ROE 23.5%, operating margin 21.4%. FCF turned positive in FY2025 (+¥19B). Every reactor restart = Organo revenue.

WHY 10.0%: Increased from 8% because this is the portfolio's best quality name. Provides 'operations' exposure — revenue from ongoing reactor maintenance, not just construction/build-out.

What could go wrong: Reactor restart pace slows; semiconductor ultrapure water business faces competition.

Monitoring trigger: If P/B expands >6x without earnings support, trim to 7%. Watch for new reactor restart announcements — each one is an Organo revenue event.

24.0x
PE
31.8x
Fwd PE
23.5%
ROE
19.4%
Op Margin
24%
D/E
1.3%
Yield

7004.T — KANADEVIA CORPORATION — 10.0% MEDIUM Decommissioning

WHY this stock: Fukushima decommissioning cask manufacturer with specific TEPCO JV ('Toso Mirai Manufacturing'). First domestic maker of used fuel transport casks since 1978. ¥22 trillion, 30-40 year revenue stream. Name changed from Hitachi Zosen Oct 2024 — databases still show old name.

WHY 10.0%: Corrected PE is 17.4x (not our original 10.2x). FCF is negative (-¥12.8B). D/E 0.88. Not a quality compounder — it's a specific-catalyst value play on the decommissioning contract.

What could go wrong: Fukushima decommissioning timeline extends; TEPCO JV production delays; balance sheet stress from D/E 0.88 + negative FCF.

Monitoring trigger: If D/E exceeds 1.0 or FCF remains negative for 2+ more periods, cut to 5%. If TEPCO JV begins shipping casks (revenue recognition), consider increasing.

10.2x
PE
8.0x
Fwd PE
5.8%
ROE
2.0%
Op Margin
88%
D/E
2.3%
Yield

6302.T — SUMITOMO HEAVY INDUSTRIES — 10.0% MEDIUM Nuclear Medicine

WHY this stock: Sole Japanese manufacturer of PET cyclotrons (100+ deliveries). World's first approved BNCT (Boron Neutron Capture Therapy) cancer treatment system (NeuCure). Japan nuclear medicine market growing $550M → $2.54B by 2031 (21.2% CAGR). P/B 0.88 (below book) with 2.9% dividend yield.

WHY 10.0%: Unique exposure to nuclear technology outside of power generation. BNCT system is first-in-world. P/B below book provides downside cushion. FCF positive (¥11B).

What could go wrong: BNCT adoption slower than expected; cyclotron demand matures; nuclear medicine not large enough segment to move the stock.

Monitoring trigger: Track BNCT installation announcements and nuclear medicine market size updates. If no BNCT progress in 12 months, reduce to 5%.

19.2x
PE
14.8x
Fwd PE
4.7%
ROE
5.3%
Op Margin
37%
D/E
2.9%
Yield

6370.T — KURITA WATER INDUSTRIES — 8.0% MEDIUM Nuclear Operations

WHY this stock: Nuclear cooling water chemistry specialist + semiconductor ultrapure water leader. Dual nuclear + semiconductor theme. FCF strongly positive (¥25B). Op margin 13.7%. As reactors restart and semiconductor fabs are built (TSMC, Rapidus, Micron), Kurita's services are needed.

WHY 8.0%: Added per GPT recommendation for 'operations/maintenance' ballast. Fwd PE 20.5x (strong earnings growth expected).

What could go wrong: Semiconductor fab buildout slows; nuclear restart pace disappoints; premium valuation compresses.

Monitoring trigger: If fwd PE expands >25x without earnings revision, trim to 5%. Watch semiconductor fab capex announcements.

37.1x
PE
22.6x
Fwd PE
6.8%
ROE
14.6%
Op Margin
32%
D/E
1.4%
Yield

5310.T — TOYO TANSO CO LTD — 7.0% LOW Next-Gen Materials

WHY this stock: Produces isotropic graphite for HTGR core components, fusion reactor wall materials, AND semiconductor graphite. Recently received order for high-temperature micro-reactor graphite (TSE disclosure). Dual nuclear + semiconductor graphite exposure in ¥114B micro-cap. D/E only 0.06.

WHY 7.0%: Corrected fwd PE is 21.8x (not 11.7x) — no longer 'cheap.' FCF is negative (-¥5.8B) from capacity expansion capex. This is optionality, not value. 7% reflects optionality sizing.

What could go wrong: HTGR/fusion timelines extend indefinitely; semiconductor graphite demand weakens; illiquidity (¥114B market cap).

Monitoring trigger: If additional HTGR or micro-reactor graphite orders disclosed, consider increasing to 10%. If no new nuclear orders in 12 months, reduce to 3%.

20.6x
PE
11.7x
Fwd PE
5.7%
ROE
11.0%
Op Margin
6%
D/E
2.7%
Yield

5302.T — NIPPON CARBON CO — 5.0% LOW Next-Gen Materials

WHY this stock: Nuclear graphite supplier since 1957 + lithium-ion battery anode materials. Trailing PE 10.6x — cheapest in portfolio. P/B 0.81 (below book). Dividend yield 4.3% — highest in portfolio. FCF marginally positive (+¥0.8B). Dual nuclear + EV materials exposure.

WHY 5.0%: Deep value + yield sleeve. Forward PE 19.6x is much higher than trailing (10.6x) — market expects earnings to decline. ¥51B market cap = very illiquid.

What could go wrong: Earnings decline materializes; illiquidity makes exits costly.

Monitoring trigger: If trailing PE expands >15x (earnings declining), reassess. Hold for yield (4.3%) as long as dividend is maintained.

10.6x
PE
10.3x
Fwd PE
8.7%
ROE
14.3%
Op Margin
16%
D/E
4.3%
Yield

5. Portfolio Construction

9
Holdings
50.0%
Top-3
0.1276
HHI
~7.8
Eff. Names

Layer / Sector Breakdown

LayerWeightStocks
SMR / Construction 35.0% 6841.T, 5631.T
Nuclear Operations 33.0% 6504.T, 6368.T, 6370.T
Next-Gen Materials 12.0% 5310.T, 5302.T
Decommissioning 10.0% 7004.T
Nuclear Medicine 10.0% 6302.T

Weights Table

StockTickerWeightConvictionRationale
YOKOGAWA ELECTRIC CORP 6841.T 18.0% HIGH Best quality-to-valuation ratio. ROE 12.2%, op margin 14.6%, D/E only 0.05. FCF ...
JAPAN STEEL WORKS 5631.T 17.0% HIGH Monopoly is irreplaceable but reduced from 25% due to negative operating CF (-¥4...
FUJI ELECTRIC CO. LTD. 6504.T 15.0% HIGH Dual-theme (nuclear + EV) at PE 18.6x with ROE 11.8%, D/E 0.13, FCF +¥51B. Both ...
ORGANO CORP 6368.T 10.0% HIGH Increased from 8% because this is the portfolio's best quality name. Provides 'o...
KANADEVIA CORPORATION 7004.T 10.0% MEDIUM Corrected PE is 17.4x (not our original 10.2x). FCF is negative (-¥12.8B). D/E 0...
SUMITOMO HEAVY INDUSTRIES 6302.T 10.0% MEDIUM Unique exposure to nuclear technology outside of power generation. BNCT system i...
KURITA WATER INDUSTRIES 6370.T 8.0% MEDIUM Added per GPT recommendation for 'operations/maintenance' ballast. Fwd PE 20.5x ...
TOYO TANSO CO LTD 5310.T 7.0% LOW Corrected fwd PE is 21.8x (not 11.7x) — no longer 'cheap.' FCF is negative (-¥5....
NIPPON CARBON CO 5302.T 5.0% LOW Deep value + yield sleeve. Forward PE 19.6x is much higher than trailing (10.6x)...
Rebalancing Rules: Quarterly review (Jun, Sep, Dec, Mar). Semiannual rebalance (Jun 30 + Dec 31). Drift control: rebalance if any position deviates >25% from target. Cut 25-50% if: fwd PE expands >50% without earnings revision, D/E worsens >0.3, or FCF negative for 2+ periods.

6. Future Plan

Earnings Calendar

DateCompanyWhat to Watch
2026-04-28 FUJI ELECTRIC CO. LTD. Earnings announcement for 6504.T
2026-04-28 SUMITOMO HEAVY INDUSTRIES Earnings announcement for 6302.T
2026-05-07 YOKOGAWA ELECTRIC CORP Earnings announcement for 6841.T
2026-05-07 KURITA WATER INDUSTRIES Earnings announcement for 6370.T
2026-05-12 KANADEVIA CORPORATION Earnings announcement for 7004.T
2026-05-13 JAPAN STEEL WORKS Earnings announcement for 5631.T
2026-05-13 ORGANO CORP Earnings announcement for 6368.T

When to Add / Trim

StockWeightTrigger
6841.T (YOKOGAWA ELECTRIC CORP) 18.0% If Rolls-Royce SMR project milestones slip, reassess nuclear optionality premium. Watch May earnings for SMR revenue recognition timing.
5631.T (JAPAN STEEL WORKS) 17.0% If operating CF remains negative in FY2026 results (May 2026), reduce to 12%. If inventory converts to revenue (OCF turns positive), increase back to 20%.
6504.T (FUJI ELECTRIC CO. LTD.) 15.0% Watch May earnings for nuclear instrumentation order flow and power semi backlog. If either segment weakens, reassess dual-theme premium.
6368.T (ORGANO CORP) 10.0% If P/B expands >6x without earnings support, trim to 7%. Watch for new reactor restart announcements — each one is an Organo revenue event.
7004.T (KANADEVIA CORPORATION) 10.0% If D/E exceeds 1.0 or FCF remains negative for 2+ more periods, cut to 5%. If TEPCO JV begins shipping casks (revenue recognition), consider increasing.
6302.T (SUMITOMO HEAVY INDUSTRIES) 10.0% Track BNCT installation announcements and nuclear medicine market size updates. If no BNCT progress in 12 months, reduce to 5%.
6370.T (KURITA WATER INDUSTRIES) 8.0% If fwd PE expands >25x without earnings revision, trim to 5%. Watch semiconductor fab capex announcements.
5310.T (TOYO TANSO CO LTD) 7.0% If additional HTGR or micro-reactor graphite orders disclosed, consider increasing to 10%. If no new nuclear orders in 12 months, reduce to 3%.
5302.T (NIPPON CARBON CO) 5.0% If trailing PE expands >15x (earnings declining), reassess. Hold for yield (4.3%) as long as dividend is maintained.

Rebalance Dates

2026-06-30


7. Supply Chain Evidence

Evidence levels: CONFIRMED named in press release/teardown/filing | PROBABLE industry standard/trade show | INFERRED logical but unproven

Evidence summary: 19 total links — 14 confirmed, 4 probable, 1 inferred
EvidenceSupplierCustomerProductDetail
CONFIRMED FUJI ELECTRIC CO. LTD. Honda Motor Co. IGBT power modules for EV inverters Honda named as IGBT customer in Fuji Electric article. Honda is explic...
CONFIRMED FUJI ELECTRIC CO. LTD. Robert Bosch GmbH SiC power semiconductor collaboration — joint deve... Fuji Electric and Bosch agreed to collaborate on SiC power semiconduct...
CONFIRMED FUJI ELECTRIC CO. LTD. Vestas Wind Systems Large-capacity IGBT modules for wind turbines (var... Partnership since 2017. Fuji Electric supplies IGBT modules for Vestas...
CONFIRMED FUJI ELECTRIC CO. LTD. Beverage/food companies (vending) Vending machines — Fuji Electric is Japan's leadin... Fuji Electric is one of Japan's top 2 vending machine makers. Major re...
CONFIRMED FUJI ELECTRIC CO. LTD. JNFL (Rokkasho) 300-channel radiation monitoring panel — largest i... Fuji Electric's own product page names JNFL as customer for 300-channe...
CONFIRMED FUJI ELECTRIC CO. LTD. All Japanese nuclear utilities (~95% share) Nuclear radiation monitoring systems — 95% domesti... Fuji Electric holds approximately 95% market share in Japan nuclear ra...
CONFIRMED FUJI ELECTRIC CO. LTD. Coca-Cola Bottlers Japan Beverage vending machines + world's first hydrogen... Joint hydrogen vending machine at EXPO 2025 Osaka. CCBJI is core vendi...
CONFIRMED FUJI ELECTRIC CO. LTD. Landsvirkjun (Iceland) Two 45 MW geothermal steam turbines (Theistareykir... Supply contract confirmed. Units commissioned 2017-2018
CONFIRMED FUJI ELECTRIC CO. LTD. KenGen (Kenya) Geothermal turbine for Olkaria I Unit 6 (70 MW) + ... EPC sub-contract via Marubeni. Olkaria operational 2022
PROBABLE FUJI ELECTRIC CO. LTD. Japanese electric utilities (nuclear monitoring) Nuclear radiation monitoring systems, personal dos... Fuji Electric has 65+ year nuclear monitoring history. Named in global...
PROBABLE FUJI ELECTRIC CO. LTD. Global automotive Tier 1s (unnamed) IGBT and SiC power modules for EV/HEV inverters an... Fuji Electric is top-5 global IGBT maker alongside Infineon, Mitsubish...
CONFIRMED YOKOGAWA ELECTRIC CORP Rolls-Royce SMR Data Processing and Control Systems (DPCS) for SMR... Joint press release 2 Feb 2026. Covers first units of global SMR fleet...
CONFIRMED YOKOGAWA ELECTRIC CORP Saudi Aramco CENTUM VP DCS + autonomous AI control agents (FKDP... Corporate Procurement Agreement since 2012. Oct 2025: AI agents commis...
CONFIRMED YOKOGAWA ELECTRIC CORP Shell OpreX Robot Management + Shell ORE AI tool for pla... June 2025 joint press release. Long-term agreement with pilot at two S...
CONFIRMED YOKOGAWA ELECTRIC CORP ADNOC (GASCO, ADCO, TAKREER) ICSS, ESD, fire & gas systems, automation. AED 2.6... ~$200M orders (2010); AED 2.6B ($708M) framework agreement for ICSS, E...
CONFIRMED YOKOGAWA ELECTRIC CORP PetroChina (Guangxi Petrochemical) CENTUM DCS, OMS, OTS, PRM for 10 MT/year refinery Named customer reference on Yokogawa website
INFERRED YOKOGAWA ELECTRIC CORP JNFL Rokkasho Radiation monitoring panel / instrumentation CORRECTION: No public source confirms Yokogawa as Rokkasho radiation p...
PROBABLE YOKOGAWA ELECTRIC CORP ČEZ (Czech Republic) — via Rolls-Royce SMR DPCS for SMR fleet (indirect via Rolls-Royce SMR) ČEZ selected Rolls-Royce SMR for up to 3 GW. Yokogawa agreement covers...
PROBABLE YOKOGAWA ELECTRIC CORP Japanese nuclear utilities (TEPCO, Kansai, etc.) Nuclear plant instrumentation and control systems Yokogawa dominant in Japan industrial I&C. States 'products used in nu...

8. Data Quality Notes

2 FCF-negative holding(s): 7004.T (¥-3B), 5310.T (¥-10B)— review at next earnings. Negative FCF + high dividend yield = sustainability risk.

9. Sources

DataSourceDate
Stock fundamentalsYahoo Finance (yfinance)2026-04-11
Stock universeJ-Quants API (JPX)Synced periodically
Supply chain evidenceWeb research + company press releasesVarious (see evidence dates)
Key datesyfinance earnings calendar + manual catalysts2026-04-11
DD narrativeQwen 3.5 via Ollama (local LLM)Pipeline run
Research frameworkEquity Peer Comparison Template (24 sections)Reference

Auto-generated by JPstock-agent pipeline | 2026-04-11
Follows Equity Peer Comparison framework — see templates/equity_peer_comparison_template_full.md for full 24-section reference
AI-assisted research, not investment advice