The hourglass: where one company or one country controls an entire step of AI chip production — from the machines that pattern the silicon to the packaging that assembles the final chip. Measured market-share HHI where a tier-1/2 source publishes shares (HBM, foundry, EUV; cloud as a top-3 lower bound) and an explicit sourced-unavailable state where none does, plus single-source dependency identification. Each figure is a single-layer market-share HHI for one market, not the portfolio-weighted supply-chain HHI the Stress Index reports across 93 CSET steps; the two are not directly comparable. Relationships draw from the full dependency graph. Hover any node to trace its downstream dependencies.
ASML is the sole manufacturer of EUV lithography machines; no alternative supplier exists at any price. No other node in the semiconductor supply chain sits this close to a single point of failure.
The right-hand column shows two separate judgments per layer: an editorial chokepoint-criticality level (assessed supply-chain importance, tier 4 — used only to sort and color, computed from nothing) and the measured concentration state. Measured figures, each recomputed in code from published shares: HBM HHI 4,174 (Counterpoint Q3 2025 revenue shares 57/22/21, tier 2); Fabrication HHI 5,007 (TrendForce FY2025 named top-6 — a named-share lower bound, tier 2); EUV sub-layer HHI 10,000 (ASML sole supplier, tier 1); Cloud HHI ≥ 1,421 (Synergy Q4 2025 top-3 lower bound, tier 2 — ~37% of the market unattributed, so the true value is higher). Layers with no tier-1/2 share publication render “sourced-unavailable” (Advanced Packaging; Materials; Chip Design carries a tier-3 share band only), and AI Labs carry no HHI at all — compute consumers, not a supply market. Measured HHIs above 2,500 exceed the “highly concentrated” threshold of the 2010 DOJ/FTC Horizontal Merger Guidelines (the 2023 Guidelines lower that line to 1,800); the comparison applies only to measured figures, never to editorial weights.Each layer shows two separate judgments. The colored level is our editorial assessment of how critical that supply-chain step is — it is not computed from any data. The HHI number, where one appears, is a measured market-concentration figure built from published market shares, and each one names its source, year, and authority tier inline. Where no reliable share data is published, the display says “sourced-unavailable” rather than estimating; AI labs get no number at all because they buy compute rather than sell it. A measured HHI above 2,500 counts as “highly concentrated” under the 2010 US merger guidelines (the 2023 guidelines use 1,800). Three measured layers clear that bar: HBM memory, chip fabrication, and EUV lithography equipment — where one company, ASML, is the only supplier on Earth.
Frontier-facility callout. Anthropic’s compute access also includes the entire Colossus 1 facility (SpaceX-owned post-merger; Memphis, >300 MW, >220K NVIDIA GPUs) under a 100% lease announced 2026-05-06. Colossus 1 is single-tenant — not a cloud provider — and is therefore excluded from the Cloud & Infrastructure layer’s concentration count. Sources: xAI announcement (Tier 1), DataCenterDynamics 2026-05-06 (Tier 2).Anthropic also has exclusive access to the entire Colossus 1 facility in Memphis (over 220,000 NVIDIA GPUs, >300 MW), owned by SpaceX since its 2026 merger with xAI and leased 100% to Anthropic from 2026-05-06. We track this separately from the cloud-provider concentration layer because it is a single-tenant lease, not a shared cloud service. Sources: xAI and DataCenterDynamics.
Methodology
Two ingredients, kept strictly separate. (1) Measured concentration. Where a tier-1/2 source publishes market shares, the HHI is recomputed in code from those shares: HBM 4,174 (Counterpoint Q3 2025: 57² + 22² + 21²); Fabrication 5,007 as a named-share lower bound (TrendForce FY2025: 69.9² + 7.2² + 5.32² + 4.35² + 3.87² + 2.6²); EUV sub-layer 10,000 (ASML 2025 Annual Report + Q4-2025 6-K, tier 1 — ASML is the sole EUV supplier: 48 systems recognized 2025, sales +39% to €11.6B); Cloud ≥ 1,421 as a top-3 lower bound (Synergy Q4 2025: 28² + 21² + 14²; ~37% of the market is unattributed, so the true value is strictly higher). Where no such source exists the display says sourced-unavailable — Advanced Packaging (the TrendForce capacity trajectory is not a share; the circulating “40% revenue share” is paywalled and unverifiable), Materials (the Omdia per-supplier wafer breakdown has no public locus), and the broader Equipment market beyond EUV.
Chip Design publishes a share band only: NVIDIA ~80–85% of merchant AI accelerators (tier-3 analyst band). Squaring a mid-band share (~82%) would alone contribute ≈ 6,700 HHI points — far above any concentration threshold — but that arithmetic inherits the band’s tier-3 status and its denominator sensitivity (counting captive ASICs like TPU and Trainium moves NVIDIA toward ~75%; excluding ASICs entirely moves it above 90%), so no HHI is published for this layer. The OECD’s “over 80%” GPU line (Competition in AI Infrastructure, Nov 2025, p.14 §2.3.1) is itself a tier-3 analyst estimate (Farooque, Yahoo Finance, ~85%) reported by the OECD — a citation chain, not an OECD measurement. AI Labs carry no HHI at all: labs are compute consumers, not suppliers in a defined market (context: Menlo Nov 2025 enterprise API-spend survey, n=495, tier 3; Epoch AI compute-share estimates, tier 2). Advanced node: Taiwan ~92% of leading-edge pure-play foundry manufacturing (CSET “No Permits, No Fabs”, VerWey 2021) is a country-level share including UMC and PSMC — not a TSMC company share; no tier-1/2 company-level advanced-node share exists.
(2) Editorial importance weights. Entity block sizes use the measured shares where the layer’s full charted set is published (HBM, Fabrication) and assessed supply-chain-importance weights elsewhere (tier 4, informed by CSET TechInsights 2024, a licensed supply-chain database, and SEC EDGAR). Weights order the visual; they are never squared into any displayed or exported number. For empirically derived supply-chain relationships with relationship values and price correlations, see the Supply Chain Explorer.
| Layer | Criticality (editorial) — Editorial chokepoint-criticality assessment (moderate / high / extreme) — assessed supply-chain importance, authority tier 4. NOT an HHI band; the measured concentration state is in the next column. | Measured concentration — Herfindahl–Hirschman Index recomputed in code from published market shares (range 0–10,000). "≥" marks lower bounds; "sourced-unavailable" means no tier-1/2 share publication exists; AI labs carry no HHI because they consume rather than supply compute. Never computed from editorial weights. | Basis (metric · source · vintage · tier) | Top nodes (editorial importance order) — Ordered by block-sizing weight — the measured share where the layer’s full charted set is published (HBM, Fabrication), otherwise editorial supply-chain-importance weight. Ordering only; weights are never rendered as market-share percentages. |
|---|---|---|---|---|
| AI Labs · Frontier compute consumers | moderate | NO HHI — consumer layer | No HHI: AI labs are frontier compute consumers, not suppliers in a defined product market. Context stats (hard scope labels — NOT market shares in the HHI sense): US-enterprise LLM API spend Anthropic 40 / OpenAI 27 / Google 21 (Menlo Ventures survey n=495, Nov 2025, tier 3); OpenAI ~10–15% of world operational AI compute and top-five labs combined <50% at end-2025 (Epoch AI estimate, tier 2). | OpenAI · US; Google DeepMind · GB; Anthropic · US |
| Cloud & Infrastructure · Compute deployment | moderate | HHI ≥ 1,421 — top-3 lower bound | LOWER BOUND (top-3 only): 28² + 21² + 14² = 1,421 from Synergy Research Group Q4 2025 worldwide cloud infrastructure revenue shares (tier 2). The remaining ~37% (Oracle, CoreWeave, Alibaba, long tail) is unattributed — the true HHI is strictly higher. | Amazon Web Services · US; Microsoft Azure · US; Google Cloud · US |
| Chip Design · GPU & accelerator designers | high | HHI — sourced-unavailable (tier-1/2) | No HHI at tier-1/2. Share band: NVIDIA ~80–85% of merchant AI accelerators (tier-3 analyst band, 2025). Market-definition note: including captive ASICs (TPU, Trainium) moves NVIDIA toward ~75%; excluding ASICs entirely moves it above 90%. The band-squaring arithmetic appears in methodology text only, with caveats; the OECD "over 80%" line is a disclosed tier-3 citation chain (Farooque via OECD), not an OECD measurement. | NVIDIA Corporation · US; Advanced Micro Devices · US; Broadcom Inc · US |
| Advanced Packaging · CoWoS, InFO, chiplet integration | high | HHI — sourced-unavailable | No tier-1/2 share publication for advanced packaging (CoWoS) — HHI sourced-unavailable. Capacity context (TrendForce, tier 2): ~75K wafers/month end-2025 → ~130K projected end-2026; TSMC dominant with ASE (SPIL) and Amkor as overflow. Capacity is not a market share. | TSMC (CoWoS) · TW; ASE Technology · TW; Amkor Technology · US |
| HBM Memory · AI accelerator memory | high | HHI 4,174 — measured | Measured: 57² + 22² + 21² = 4,174 from Counterpoint Research Q3 2025 HBM revenue shares (SK Hynix / Samsung / Micron — all suppliers named; tier 2, via Semiecosystem). Samsung recovered 15% → 22% Q2→Q3 2025 on HBM3E qualification; refresh on Q4 publication. | SK Hynix · KR; Samsung · KR; Micron Technology · US |
| Fabrication · Semiconductor foundries | extreme | HHI 5,007 — named-share lower bound | Named-share lower bound: 69.9² + 7.2² + 5.32² + 4.35² + 3.87² + 2.6² ≈ 5,007, recomputed in code from TrendForce FY2025 foundry revenue shares (tier 2, via Taipei Times 2026-03-14). Advanced node: Taiwan ~92% of leading-edge pure-play foundry manufacturing (CSET/VerWey 2021, COUNTRY-level incl. UMC + PSMC); no company-level advanced-node HHI exists at tier-1/2. | TSMC · TW; Samsung Foundry · KR; SMIC · CN |
| Equipment · Lithography, deposition, etch | extreme | HHI 10,000 — EUV sub-layer only | EUV sub-layer (tier 1): ASML 100% of EUV lithography systems → HHI 10,000 — the strongest figure in this dataset. Source: ASML 2025 Annual Report, financial-performance section + Q4-2025 investor presentation (Form 6-K, Jan 28, 2026) (48 EUV systems recognized 2025, 4 EXE + 44 NXE; EUV system sales +39% to €11.6B). Broader wafer-fab equipment market: sourced-unavailable — no HHI published. The prior blended equipment figure is retired. | ASML Holding · NL; Applied Materials · US; Lam Research · US |
| Materials & Chemicals · Wafers, photoresists, specialty gases | high | HHI — sourced-unavailable | Sourced-unavailable, split layer: silicon-wafer per-supplier shares have no public locus (Omdia subscription-gated; ledger 2026-06-09) — a wafer HHI does not publish; photoresist/specialty-chemical shares have no tier-1/2 publication. Country-level context: Japan ~56% of global silicon wafers (CSET TechInsights 2024, tier 2). | Shin-Etsu Chemical · JP; SUMCO Corporation · JP; JSR Corporation · JP |