Ranked by reported Q1 2026 13F market value
Share of total reported institutional value in MRX held by the largest 10 / 25 filers.
| # | Institution | Shares Held | Market Value | QoQ Change | Ownership % | % of Fund |
|---|---|---|---|---|---|---|
| 1 | BlackRock, Inc. | 4.4M | $195.7M | +10.7% | 6.102% | 0.00% |
| 2 | Capital International Investors | 3.5M | $155.5M | 0.0% | 4.849% | 0.04% |
| 3 | FMR LLC | 3.5M | $155.2M | +160.9% | 4.841% | 0.01% |
| 4 | LOOMIS SAYLES & CO L P | 1.9M | $85.5M | -0.9% | 2.667% | 0.12% |
| 5 | SAMLYN CAPITAL, LLC | 1.7M | $75.3M | +47.9% | 2.348% | 1.29% |
| 6 | TWO SIGMA INVESTMENTS, LP | 1.7M | $75.0M | +86.2% | 2.338% | 0.06% |
| 7 | JENNISON ASSOCIATES LLC | 1.6M | $71.6M | +8.9% | 2.234% | 0.05% |
| 8 | WILLIAM BLAIR INVESTMENT MANAGEMENT, LLC | 1.6M | $69.8M | -9.9% | 2.177% | 0.23% |
| 9 | ALLIANCEBERNSTEIN L.P. | 1.7M | $66.4M | -1.1% | 2.405% | 0.02% |
| 10 | Invesco Ltd. | 1.4M | $61.2M | +6.0% | 1.909% | 0.01% |
| 11 | Grandeur Peak Global Advisors, LLC | 1.3M | $59.1M | -25.5% | 1.842% | 13.84% |
| 12 | VICTORY CAPITAL MANAGEMENT INC | 1.3M | $58.6M | +96.2% | 1.828% | 0.04% |
| 13 | ROYCE & ASSOCIATES LP | 1.3M | $55.8M | -0.6% | 1.742% | 0.55% |
| 14 | Ophir Asset Management Pty Ltd | 1.2M | $55.6M | +14.7% | 1.733% | 6.47% |
| 15 | GRANAHAN INVESTMENT MANAGEMENT INC/MA | 1.2M | $54.6M | -11.1% | 1.701% | 2.64% |
| 16 | Artisan Partners Limited Partnership | 1.2M | $54.2M | +34.5% | 1.692% | 0.09% |
| 17 | AMERIPRISE FINANCIAL INC | 954K | $42.5M | +11.0% | 1.327% | 0.01% |
| 18 | Allspring Global Investments Holdings, LLC | 909K | $39.1M | +11.5% | 1.263% | 0.07% |
| 19 | STATE STREET CORP | 873K | $38.9M | +4.0% | 1.214% | 0.00% |
| 20 | HEALTHCARE OF ONTARIO PENSION PLAN TRUST FUND | 729K | $32.5M | -34.6% | 1.014% | 0.05% |
| 21 | GEODE CAPITAL MANAGEMENT, LLC | 726K | $32.4M | +2.4% | 1.010% | 0.00% |
| 22 | WELLINGTON MANAGEMENT GROUP LLP | 655K | $29.2M | -13.7% | 0.911% | 0.01% |
| 23 | Qube Research & Technologies Ltd | 593K | $26.4M | -22.4% | 0.824% | 0.03% |
| 24 | WESTWOOD HOLDINGS GROUP INC | 538K | $24.0M | -4.7% | 0.748% | 0.17% |
| 25 | Praetorian PR LLC | 500K | $22.3M | 0.0% | 0.695% | 8.11% |
denotes a marquee investor (Buffett, Burry, ARK, Tiger Global, Pershing Square, Baupost and other widely-followed managers). “% of Fund” shows how much of that investor’s total 13F portfolio is invested in MRX — a direct measure of their conviction.
Filings activity in MRX during Q1 2026, grouped by how each filer changed its position.
8 quarters of 13F filings · Δ columns show change vs prior quarter
| Quarter | Inst. Holders | Δ Holders | Ownership % | Δ Ownership | Total 13F Value | Δ Value |
|---|---|---|---|---|---|---|
| Q1 2026 | 201 | +4.7% | 48.19% | +6.20 pp | $2.15B | +15% |
| Q4 2025 | 192 | +2.1% | 41.99% | +4.64 pp | $1.87B | +12% |
| Q3 2025 | 188 | 5.1% | 37.35% | 29.32 pp | $1.66B | 44% |
| Q2 2025 | 198 | +65% | 66.67% | +41.68 pp | $2.97B | +167% |
| Q1 2025 | 120 | +12% | 24.99% | +6.79 pp | $1.11B | +37% |
| Q4 2024 | 107 | +51% | 18.20% | +9.68 pp | $811M | +114% |
| Q3 2024 | 71 | +18% | 8.52% | +2.39 pp | $380M | +39% |
| Q2 2024 | 60 | — | 6.13% | — | $273M | — |
Source: SEC 13F institutional filings. Ownership % requires market cap data and will show once linked. Δ columns compare to the immediately prior filed quarter.
Quick answers to the most common questions about buying MRX stock.
Based on Q1 2026 13F filings, institutional ownership of Marex Group plc Ordinary Shares stands at 48.2%, held across 201 reporting institutions.
BlackRock, Inc. is the largest reported institutional holder of MRX, with approximately 4,389,325 shares worth $0.20B as of Q1 2026.
Yes — 1 widely-followed marquee investor appear among the top 25 institutional holders of MRX, including TWO SIGMA INVESTMENTS, LP.
Our composite Smart Money Score for MRX is 61 out of 100 (Bullish). It combines net institutional buying activity, ownership shift, marquee investor presence, and holder-count growth.
41 institutions opened new positions in MRX during Q1 2026, while 32 fully exited. 127 added to existing positions and 31 trimmed.
MRX institutional ownership rose by 6.20 percentage points quarter-over-quarter, with a net change of +9 holders.
The top 10 institutions account for 47.1% of all reported 13F value in MRX, and the top 25 account for 76.2%.
All data is sourced from SEC Form 13F filings, which institutional investment managers with at least $100M in assets are required to file each quarter. We process every 13F filing from EDGAR and recompute the aggregates after each cycle. Insider transactions are sourced from Form 4 filings.
Marex Group plc Ordinary Shares (MRX) Institutional Ownership