SEI Investments Company
MX ˙ BMV ˙ US7841171033
SecurityMX:SEIC / SEI Investments Company
InstitutionWorldquant Millennium Advisors Llc
Latest Disclosed Ownership37,536 shares
Latest Disclosed Value $ 2,945,450
Worldquant Millennium Advisors Llc reports 1.78% decrease in ownership of SEIC / SEI Investments Company

On May 15, 2026 - Worldquant Millennium Advisors Llc filed a 13F-HR form disclosing ownership of 37,536 shares of SEI Investments Company (MX:SEIC) valued at $2,945,450 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 17, 2026 disclosing 38,218 shares of SEI Investments Company. This represents a change in shares of -1.78% during the quarter.

Institutional Ownership: 13F and NPORT Filings

The Security and Class in the table below are shown exactly as filed by the investor. We do our best to track continuity of investments through acquisitions, and this will be reflected in the table as changes in names. In addition to descriptive data, performance of the investment is shown over time. To calculate quarterly performance, we first calculate cost basis of the shares purchased during the quarter, then use that to calculate gross profit. Quarterly return is Gross Profit / Starting Portfolio value.

Note that cost basis is calculated and stored in thousands, so small quarterly changes in shares frequently result in a cost basis of zero.

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Disclosed Equity Positions (from 13F/NPORT Filings)
File
Date		 Effective
Date		Form Security Class ID Avg Price
Paid (Est)		 Reported
Shares		 ΔShares ΔShares
(%)		 Reported
Value
(x1000)		 ΔValue
(%)		 Alloc
(%)		 ΔAlloc ΔAlloc (%) Cost Basis
(x1000)		 Unrealized
Gain/Loss
(x1000)
2026-05-15 2026-03-31 13F SEI INVTS COM 784117103 37,536 -682 -1.78 2,945 -6.03 0.0114
2026-02-17 2025-12-31 13F SEI INVTS COM 784117103 38,218 11,530 43.20 3,135 38.43 0.0122
2025-11-14 2025-09-30 13F SEI INVTS COM 784117103 26,688 -67,229 -71.58 2,264 -73.17 0.0098
2025-08-14 2025-06-30 13F SEI INVTS COM 784117103 93,917 65,207 227.12 8,439 278.77 0.0419
2025-05-15 2025-03-31 13F SEI INVTS COM 784117103 28,710 3,888 15.66 2,229 8.84 0.0140
2025-02-14 2024-12-31 13F SEI INVTS COM 784117103 24,822 -499 -1.97 2,047 16.90 0.0133
2024-11-14 2024-09-30 13F SEI INVTS COM 784117103 25,321 -277 -1.08 1,752 5.80 0.0128
2024-08-14 2024-06-30 13F SEI INVTS COM 784117103 25,598 14,356 127.70 1,656 104.83 0.0151
2024-05-15 2024-03-31 13F SEI INVTS COM 784117103 11,242 -4,188 -27.14 808 -17.55 0.0100
2024-02-14 2023-12-31 13F SEI INVTS COM 784117103 15,430 10,265 198.74 981 215.11 0.0137
2023-11-14 2023-09-30 13F SEI INVTS COM 784117103 5,165 5,165 311 0.0048
2023-02-14 2022-12-31 13F SEI INVTS COM 784117103 0 -14,688 -100.00 0 -100.00
2022-11-14 2022-09-30 13F SEI INVTS COM 784117103 14,688 -131,719 -89.97 720 -90.90 0.0175
2022-08-15 2022-06-30 13F SEI INVTS COM 784117103 146,407 -4,303 -2.86 7,909 -12.84 0.2264
2022-05-16 2022-03-31 13F SEI INVTS COM 784117103 150,710 -13,938 -8.47 9,074 -9.57 0.2212
2022-02-14 2021-12-31 13F SEI INVTS COM 784117103 164,648 74,886 83.43 10,034 88.50 0.1994
2021-11-15 2021-09-30 13F SEI INVTS COM 784117103 89,762 15,272 20.50 5,323 15.32 0.1164
2021-08-16 2021-06-30 13F SEI INVTS COM 784117103 74,490 0 0.00 4,616 1.70 0.1020
2021-05-17 2021-03-31 13F SEI INVTS COM 784117103 74,490 0 0.00 4,539 6.03 0.0964
2021-02-16 2020-12-31 13F SEI INVTS COM 784117103 74,490 0 0.00 4,281 13.31 0.0936
2020-11-16 2020-09-30 13F SEI INVTS COM 784117103 74,490 0 0.00 3,778 -7.74 0.0895
2020-08-14 2020-06-30 13F SEI INVTS COM 784117103 74,490 -6,125 -7.60 4,095 9.61 0.0942
2020-05-14 2020-03-31 13F SEI INVESTMENTS COM 784117103 80,615 12,983 19.20 3,736 -15.65 0.0909
2020-02-14 2019-12-31 13F SEI INVESTMENTS COM 784117103 67,632 -10,131 -13.03 4,429 -3.86 0.0848
2019-11-14 2019-09-30 13F SEI INVESTMENTS COM 784117103 77,763 3,474 4.68 4,607 10.53 0.0896
2019-08-14 2019-06-30 13F SEI INVESTMENTS COM 784117103 74,289 10,908 17.21 4,168 25.85 0.0794
2019-05-14 2019-03-31 13F SEI INVESTMENTS COM 784117103 63,381 1,644 2.66 3,312 16.13 0.0785
2019-02-14 2018-12-31 13F SEI INVESTMENTS COM 784117103 61,737 11,968 24.05 2,852 -6.22 0.0844
2018-11-14 2018-09-30 13F SEI INVESTMENTS COM 784117103 49,769 5,878 13.39 3,041 10.82 0.1019
2018-08-14 2018-06-30 13F SEI INVESTMENTS COM 784117103 43,891 43,891 2,744 0.1052
Legend
Shares
The total number of shares held by the institution at the end of the reporting period (the effective date). This is provided in the filing.
Value
The total value of the shares as of the effective date. This is provided in the filing.
Avg. Share Price
The weighted average share price of the shares held by the institution. We use FIFO accounting to determine this price
Class
This is the security class as indicated by the filer. There are a variety of values for this field. Common values include "EC" = equity common, "EP" - equity preferred
Allocation (%)
The percent of the institution's portfolio that this position represents. This is provided in NPORT filings. For 13F filings, we calculate it.
Change in Allocation
The change in allocation from the prior reporting period. This is calculated as current allocation - prior allocation.
Change in Allocation (%)
The percent change in allocation from the prior reporting period. This is calculated as (current allocation - prior allocation) / prior allocation.
Cost Basis
The total cost of the shares held. This is calculated as reported shares * avg. share price
Unrealized Gain/Loss
This is the market value of the position as of the effective date minus the cost basis.