Ranked by reported Q2 2026 13F market value
Share of total reported institutional value in SEIC held by the largest 10 / 25 filers.
| # | Institution | Shares Held | Market Value | QoQ Change | Ownership % | % of Fund |
|---|---|---|---|---|---|---|
| 1 | BlackRock, Inc. | 9.9M | $870.7M | -1.8% | 8.272% | 0.01% |
| 2 | LOOMIS SAYLES & CO L P | 8.5M | $744.0M | -1.7% | 7.067% | 0.93% |
| 3 | VANGUARD PORTFOLIO MANAGEMENT LLC | 6.1M | $538.6M | +0.3% | 5.117% | 0.02% |
| 4 | VANGUARD CAPITAL MANAGEMENT LLC | 4.7M | $411.0M | -1.2% | 3.905% | 0.01% |
| 5 | STATE STREET CORP | 4.3M | $372.9M | +1.6% | 3.542% | 0.01% |
| 6 | MORGAN STANLEY | 4.1M | $361.3M | -14.1% | 3.432% | 0.02% |
| 7 | Boston Partners | 3.1M | $271.4M | +74.8% | 2.578% | 0.24% |
| 8 | GEODE CAPITAL MANAGEMENT, LLC | 3.0M | $259.1M | +4.3% | 2.461% | 0.01% |
| 9 | BANK OF AMERICA CORP /DE/ | 2.9M | $255.1M | -0.4% | 2.423% | 0.02% |
| 10 | FMR LLC | 2.5M | $220.2M | +20.0% | 2.091% | 0.01% |
| 11 | DIMENSIONAL FUND ADVISORS LP | 2.0M | $172.1M | +4.8% | 1.635% | 0.03% |
| 12 | FIRST TRUST ADVISORS LP | 1.5M | $131.7M | -17.6% | 1.251% | 0.08% |
| 13 | Invesco Ltd. | 1.1M | $97.4M | -3.0% | 0.925% | 0.01% |
| 14 | ROYCE & ASSOCIATES LP | 1.1M | $92.1M | +5.4% | 0.875% | 0.74% |
| 15 | CAISSE DE DEPOT ET PLACEMENT DU QUEBEC | 1.0M | $87.9M | -16.3% | 0.835% | 0.13% |
| 16 | Boston Trust Walden Corp | 991K | $86.9M | -4.7% | 0.826% | 0.66% |
| 17 | NORTHERN TRUST CORP | 915K | $80.2M | +1.0% | 0.762% | 0.01% |
| 18 | Bank of New York Mellon Corp | 894K | $78.4M | -4.5% | 0.745% | 0.01% |
| 19 | NORGES BANK | 887K | $77.8M | — | 0.739% | 0.01% |
| 20 | BARCLAYS PLC | 825K | $72.4M | +116.6% | 0.688% | 0.01% |
| 21 | AMERICAN CAPITAL MANAGEMENT INC | 745K | $65.4M | -3.0% | 0.621% | 2.93% |
| 22 | CHARLES SCHWAB INVESTMENT MANAGEMENT INC | 695K | $61.0M | -0.1% | 0.579% | 0.01% |
| 23 | ARROWSTREET CAPITAL, LIMITED PARTNERSHIP | 660K | $57.9M | +16.3% | 0.550% | 0.03% |
| 24 | JANE STREET GROUP, LLC | 656K | $57.5M | +2555.1% | 0.546% | 0.00% |
| 25 | Clark Capital Management Group, Inc. | 639K | $56.0M | -23.7% | 0.532% | 0.31% |
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 SEIC — a direct measure of their conviction.
Filings activity in SEIC during Q2 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 |
|---|---|---|---|---|---|---|
| Q2 2026 | 575 | +1.4% | 75.42% | +0.75 pp | $7.43B | +13% |
| Q1 2026 | 567 | +2.7% | 74.67% | +2.00 pp | $6.58B | 3.2% |
| Q4 2025 | 552 | +3.0% | 72.67% | +0.66 pp | $6.80B | 2.6% |
| Q3 2025 | 536 | 3.4% | 72.01% | 0.71 pp | $6.98B | 32% |
| Q2 2025 | 555 | +3.9% | 72.72% | 1.59 pp | $10.34B | +73% |
| Q1 2025 | 534 | +1.3% | 74.31% | +3.44 pp | $5.98B | 2.6% |
| Q4 2024 | 527 | +8.7% | 70.87% | +1.28 pp | $6.14B | +22% |
| Q3 2024 | 485 | — | 69.59% | — | $5.04B | — |
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 SEIC stock.
Based on Q2 2026 13F filings, institutional ownership of SEI Investments Company stands at 75.4%, held across 575 reporting institutions.
BlackRock, Inc. is the largest reported institutional holder of SEIC, with approximately 9,927,545 shares worth $0.87B as of Q2 2026.
Yes — 1 widely-followed marquee investor appear among the top 25 institutional holders of SEIC, including JANE STREET GROUP, LLC.
Our composite Smart Money Score for SEIC is 56 out of 100 (Neutral). It combines net institutional buying activity, ownership shift, marquee investor presence, and holder-count growth.
64 institutions opened new positions in SEIC during Q2 2026, while 59 fully exited. 373 added to existing positions and 118 trimmed.
SEIC institutional ownership rose by 0.75 percentage points quarter-over-quarter, with a net change of +8 holders.
The top 10 institutions account for 57.9% of all reported 13F value in SEIC, and the top 25 account for 75.1%.
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.
SEI Investments Company (SEIC) Institutional Ownership