State Street SPDR S&P Biotech ETF
Portfolio Exposure & Concentration
Look-through constituent allocation & index mechanics (S47B)
Securities in fund basket
Combined weight of largest 10
Alnylam Pharmaceuticals Inc.
Active industry exposures
Top 25 Holdings — XBI (S47B-01)
Statutory Form N-PORT authenticated portfolio weights with direct equity research bridge (S47B-04)
| # | Company / Security | Portfolio Weight | Equity Research |
|---|---|---|---|
| 1 | ALNYAlnylam Pharmaceuticals Inc. | 2.20% | Stock Dossier |
| 2 | MRNAModerna Inc. | 2.10% | Stock Dossier |
| 3 | BIIBBiogen Inc. | 2.00% | Stock Dossier |
| 4 | VRTXVertex Pharmaceuticals Inc. | 2.00% | Stock Dossier |
| 5 | REGNRegeneron Pharmaceuticals Inc. | 1.90% | Stock Dossier |
| 6 | ARWRArrowhead Pharmaceuticals Inc. | 1.80% | Stock Dossier |
| 7 | IONSIonis Pharmaceuticals Inc. | 1.80% | Stock Dossier |
| 8 | CRSPCRISPR Therapeutics AG | 1.70% | Stock Dossier |
| 9 | BMRNBioMarin Pharmaceutical Inc. | 1.70% | Stock Dossier |
| 10 | BNTXBioNTech SE ADR | 1.60% | Stock Dossier |
| 11 | SRPTSarepta Therapeutics Inc. | 1.60% | Stock Dossier |
| 12 | INCYIncyte Corporation | 1.50% | Stock Dossier |
| 13 | EXASExact Sciences Corp. | 1.50% | Stock Dossier |
| 14 | BGNEBeiGene Ltd. ADR | 1.40% | Stock Dossier |
| 15 | ROIVRoivant Sciences Ltd. | 1.40% | Stock Dossier |
| 16 | BEAMBeam Therapeutics Inc. | 1.30% | Stock Dossier |
| 17 | NTLAIntellia Therapeutics Inc. | 1.30% | Stock Dossier |
| 18 | BBIOBridgeBio Pharma Inc. | 1.20% | Stock Dossier |
| 19 | KYMRKymera Therapeutics Inc. | 1.20% | Stock Dossier |
| 20 | PCVXVaxcyte Inc. | 1.10% | Stock Dossier |
| 21 | KRYSKrystal Biotech Inc. | 1.10% | Stock Dossier |
| 22 | KRTXKaruna Therapeutics Inc. | 1.00% | Stock Dossier |
| 23 | RCKTRocket Pharmaceuticals Inc. | 1.00% | Stock Dossier |
| 24 | TVTXTravere Therapeutics Inc. | 0.90% | Stock Dossier |
| 25 | VIRVir Biotechnology Inc. | 0.90% | Stock Dossier |
GICS 11-Sector Allocation (S47B-02)
Industry diversification across standard economic classifications
Portfolio Breakdown & Allocation Matrix
Multi-dimensional constituent classification sourced from SEC Form N-PORT and Issuer Fact Sheets (S48-Phase 2)
Sub-sector clusters reflect concentrated industry exposures beyond broad GICS sectors.
Market Cap Tier Breakdown (S47B-05)
Weighted capital size distribution of fund holdings
Look-Through Concentration Engine (S47B-03)
Calculates aggregate effective single-stock exposure across direct holdings & pooled ETFs
// Mathematical SSOT Formulation:
W_i = w_{direct, i} + ∑_f (a_f × w_{f,i})
Real-World Institutional Use-Case:
An investor holding 5% direct AAPL equity, plus 40% in VOO and 20% in QQQ, actually bears:
Vantage Portfolios look-through alerts eliminate hidden tech over-concentration and unintended double-exposure across multi-asset portfolios.