Institutional Portfolio Overlap & Shared Holdings
Compare institutional investor portfolios using publicly disclosed SEC Form 13F filings tracked by InsiderSet. Analyze shared holdings, overlapping sector exposure, consensus smart money positions, portfolio concentration, and estimated current values across major hedge funds and institutional asset managers.
Sector portfolio overlap
Explore shared holdings and top overlapping superinvestor pairs within a sector.
Greenbrier Partners Capital Management & Lountzis Asset Management Portfolio Overlap
Shared 13F holdings between Greenbrier Partners Capital Management and Lountzis Asset Management based on latest reported SEC filings (the quarter ended March 31, 2026).
Overlap Score
89
Extremely high shared conviction
Shared Holdings
6 shared positions across both portfolios (11 holdings for Greenbrier Partners Capital Management, 52 for Lountzis Asset Management).
| Stock | Greenbrier Partners Capital Management value | Lountzis Asset Management value | Combined value | Conviction | Est. current value | Sector |
|---|---|---|---|---|---|---|
| AAPL Apple Inc. | $299.64M | $433,727 | $300.07M | 11.6% | $354.98M | Technology |
| META Meta Platforms, Inc. | $226.05M | $519,494 | $226.57M | 8.8% | $243.24M | Communication Services |
| GOOGL Alphabet Inc. | $128.64M | $13.83M | $142.48M | 7.5% | $196.59M | Communication Services |
| GOOG Alphabet Inc. | $132.74M | $1.49M | $134.24M | 5.4% | $184.06M | Communication Services |
| BRK-B Berkshire Hathaway Inc. New | $38.67M | $64.36M | $103.03M | 13.3% | — | Financial Services |
| MSFT Microsoft Corporation | $43.99M | $488,254 | $44.48M | 1.8% | $50.70M | Technology |
Largest Shared Position
Apple Inc. (AAPL) represents the largest overlapping position between Greenbrier Partners Capital Management and Lountzis Asset Management based on the latest reported SEC Form 13F filings for the quarter ended March 31, 2026. The combined disclosed value of AAPL positions reported by both investment firms is approximately $300.07M, reflecting overlapping institutional exposure to Apple Inc..
Shared Sector Exposure
| Sector | Combined value | Shared holdings |
|---|---|---|
| Communication Services | $503.28M | GOOG, GOOGL, META |
| Technology | $344.55M | AAPL, MSFT |
| Financial Services | $103.03M | BRK-B |
Consensus Smart Money Signals
Shared holdings between Greenbrier Partners Capital Management and Lountzis Asset Management may indicate overlapping long-term investment themes or broader smart money consensus toward specific companies and sectors. SEC Form 13F filings report positions, not investment intent.
- Strongest overlap by reported value: AAPL ($300.07M combined).
- Highest average portfolio weight in overlap: BRK-B (13.3% conviction score).
- Largest estimated mark-to-market gain since filing: AAPL ($54.91M vs reported combined value, where EOD data is available).
Historical Overlap Trend
The overlap between Greenbrier Partners Capital Management and Lountzis Asset Management was unchanged between Q3 2001 and Q1 2001, with 6 shared holdings in the latest period ($950.87M combined reported value) versus 6 in the prior period ($1.07B).
Overlap Score Guide
| Score | Meaning |
|---|---|
| 85–100 | Extremely high shared conviction |
| 65–84 | Strong overlap |
| 45–64 | Moderate overlap |
| 25–44 | Limited overlap |
| 0–24 | Minimal overlap |
Related Overlap Pages
- Greenbrier Partners Capital Management portfolio
- Lountzis Asset Management portfolio
- Situational Awareness Partners & Aquamarine Zurich AG Shared Holdings
- Situational Awareness Partners & TCI Fund Management Shared Holdings
- Situational Awareness Partners & Polen Capital Management Shared Holdings
- Situational Awareness Partners & Dodge & Cox Stock Fund Shared Holdings
- Situational Awareness Partners & Trian Fund Management Shared Holdings
- Most Common Institutional Holdings
- Top Institutional Investor Stock Rankings