Deep Evolve DD — 3 Stocks: SUMCO, Resonac, Kokusai Electric

Date: 2026-05-06 | Type: Scheduled Evolution Round | Stocks: 3436.T · 4004.T · 6525.T

Executive Summary

Three semiconductor supply-chain names evolved ahead of imminent earnings:

• SUMCO (3436.T) — HOLD LOW conviction. Miyazaki 200mm plant closure signals proactive capacity rationalization; Q1 2026 wafer shipments +13% YoY confirms AI-led recovery track. Profitability expected 2027.
• Resonac Holdings (4004.T) — UPGRADED LOW→MEDIUM. FY2026 PAT guidance ¥77B (2.7× prior year). Semiconductor back-end materials for AI packaging now the primary earnings driver — stock hit 52-week high today. AP01 peak-earnings watch added.
• Kokusai Electric (6525.T) — HOLD HIGH conviction. PE compressed from 48.88×→37.06× as FY2025 NI grew +61%. Q3 revenue dip is timing (deferred equipment), not demand. Service revenue rising to 44% (from 30%) improves earnings quality. Non-China exposure cut to 31%.

1. SUMCO Corporation (3436.T)

Layer: Silicon Wafers | Conviction: LOW | Status: HOLD

Thesis (Updated)

Leveraged recovery play on silicon wafer upcycle. Loss-making but 300mm AI/HBM wafer demand structurally growing (+13% Q1 2026 YoY per SEMI). Miyazaki plant 200mm production to cease by December 2026 — clear capacity rationalization signal; management pivoting entirely to AI-grade 300mm. Depreciation peaks 2026 → profitability inflection expected 2027.

Key Metrics (Updated 2026-05-06)

Supply Chain (Confirmed)

Anti-Pattern Check

• AP01 Peak Earnings: ✅ CLEAR — Still loss-making, at cyclical trough.
• AP02 Capacity Hangover: ✅ CLEAR — SUMCO closing 200mm (rationalization). Shin-Etsu+SUMCO oligopoly = disciplined capacity management.
• AP03 Concept Stock: ✅ CLEAR — 100% wafer focus, AI is structural.

Upcoming Catalyst

May 10, 2026 (4 days): Earnings — watch for (1) FY2026 revenue guide vs +9.6% consensus; (2) Miyazaki closure timeline; (3) LTA structure changes.

Thesis Breaks If

AI-driven 300mm demand softens materially AND LTA overhang extends losses beyond 2028. Trigger: SEMI Q2 2026 shipments <5% YoY growth = thesis at risk.

2. Resonac Holdings (4004.T)

Layer: SiC Substrates / Semiconductor Materials | Conviction: MEDIUM (↑ from LOW) | Status: UPGRADED

Thesis (Updated)

Dual-engine semiconductor materials play:

1. SiC substrates — confirmed multi-year supply agreement with Infineon (Jan 2023, 6-inch + 8-inch ramp); 8-inch mass production started 2025. Serves Rohm, Infineon, Soitec JV (Sept 2024).

2. Semiconductor back-end materials — CMP slurry, photoresist for AI chip packaging. Semiconductor & Electronic Materials segment at record quarterly operating profit driven by generative AI demand.

FY2026 PAT guided ¥77B (2.7× prior year's ¥29B). Core operating profit target ¥140B (+43% YoY from ¥98B). Back-end AI materials are now the primary earnings driver, not SiC alone.

Key Metrics (Updated 2026-05-06)

Supply Chain (Updated)

Anti-Pattern Check

• AP01 Peak Earnings: ⚠️ WATCH — Stock at 52-week high, +102% in 6 months. Semiconductor segment at record OP. OVERRIDE: Earnings recovery is from a depressed ¥29B base (not cyclical peak); AI back-end materials demand is structural. Distinguish SiC cyclical component from secular semiconductor materials.
• AP02 Capacity Hangover: ✅ CLEAR — SiC 8-inch ramp differentiates vs competitors.
• AP03 Concept Stock: ✅ CLEAR — Semiconductor materials 35% of revenue and growing.

Upcoming Catalyst

May 12, 2026 (6 days): Earnings — watch for (1) FY2025 actual vs ¥98B core OP; (2) FY2026 guidance ¥140B OP + ¥77B PAT confirmation; (3) Named 8-inch SiC customers.

Thesis Breaks If

FY2026 actual PAT below ¥50B (vs ¥77B guidance) at May 12 earnings. Or if hyperscaler AI capex cuts >20% weaken back-end materials demand. Or SiC losses expand beyond semiconductor segment growth.

3. Kokusai Electric Corporation (6525.T)

Layer: Deposition Equipment (Batch ALD) | Conviction: HIGH | Status: HOLD

Thesis (Updated)

~70% global share in batch ALD — essential for GAA transistors (Samsung SF2, Intel 18A) and 3D DRAM. 5 confirmed GAA process-of-record wins (CY2024). Dual award recognition: TSMC 2025 Excellent Production Support Award + Intel 2026 EPIC Supplier Award (Mar 2026).

Q3 FY2026 context: Revenue -7% YoY (¥55.9B) due to delayed equipment sales to next fiscal year — timing issue, not demand destruction. Service revenue rose to 44% of total (from 30%) — positive recurring mix shift. Non-China revenue share grew from 50% to 69% — active de-risking confirmed.

FY2027 WFE outlook: DRAM +20%, NAND +15% (company guidance). Toyama capacity doubling complete.

Key Metrics (Updated 2026-05-06)

Supply Chain (Unchanged — All Confirmed)

Anti-Pattern Check

• AP01 Peak Earnings: ⚠️ WATCH — +114% in 52 weeks. BUT Q3 -7% revenue shows this is not at operational peak. FY2027 WFE guide DRAM +20% indicates early-cycle, not late-cycle.
• AP02 Capacity Expansion: ✅ CLEAR — Kokusai is sole dominant batch ALD player; Toyama doubling is supply matching demand, not 3+ competitor race.
• AP03 Concept Stock: ✅ CLEAR — 100% semiconductor equipment. GAA is real and in production.

Upcoming Catalyst

May 13, 2026 (7 days): FY2026 full-year results + FY2027 guidance. Critical checks:

1. Revenue guide ≥¥300B for FY2027?

2. ≥20% revenue growth commitment maintained?

3. China revenue % — targeting <25%?

4. Service revenue growing toward 50%?

Thesis Breaks If

FY2027 guidance below 20% revenue growth. Or China revenue rebounds above 40%. Or DRAM/NAND capex cuts materially below FY2027 WFE forecast — would signal equipment timing issues becoming structural.

Risk Flags

AP01 Peak Earnings Watch — Resonac (4004.T)

Stock hit 52-week high (+102% in 6 months) same day as this research. Semiconductor segment at record quarterly operating profit. FY2026 PAT guided 2.7× YoY.

Assessment: Earnings recovery from depressed base (¥29B → ¥77B) is not a cyclical peak. AI back-end materials demand is structural. SiC EV component is cyclically weak — net: upgrade warranted but position sizing conservative (MEDIUM not HIGH).

AP01 Watch — Kokusai Electric (6525.T)

+114% in 52 weeks. Revenue +32% FY2025.

Assessment: Q3 FY2026 -7% revenue counters peak narrative. GAA ramp is 2025-2030 secular cycle, not late-cycle. HOLD HIGH conviction.

Valuation Guardrail — Kokusai Electric PB 7.51×

P/B above 80th percentile for quasi-cyclical equipment company.

Override justification: 70% global monopoly in batch ALD with irreplaceable position in GAA/3D DRAM transition. ROE 16.35% supports premium. This is monopoly pricing power, not cycle enthusiasm.

Valuation Guardrail — Resonac FCF Growth >15%

FY2026 PAT guidance implies FCF growth well above 15% guardrail threshold.

Override justification: Named catalyst — semiconductor back-end materials for AI packaging (structural, not extrapolated). Resonac IR guidance with detailed segment data. FCF growth is front-loaded from earnings recovery, not aggressive projection.

Data Sources

*J-Quants unavailable in cloud environment — Tier 2 web sources used for metric cross-validation.*

*Report date: 2026-05-06 | Research agent: Claude (scheduled evolve round)*

*Next evolve: stocks with May 8-14 earnings (6503.T, 6302.T, 6508.T, 6758.T prioritized)*

*This is not investment advice. All analysis is for research purposes only.*