SEI Investments Company
MX ˙ BMV ˙ US7841171033
SecurityMX:SEIC / SEI Investments Company
InstitutionOppenheimer Asset Management Inc.
Latest Disclosed Ownership19,726 shares
Latest Disclosed Value $ 1,547,899
Oppenheimer Asset Management Inc. reports 17.51% increase in ownership of SEIC / SEI Investments Company

On April 23, 2026 - Oppenheimer Asset Management Inc. filed a 13F-HR form disclosing ownership of 19,726 shares of SEI Investments Company (MX:SEIC) valued at $1,547,899 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 2, 2026 disclosing 16,787 shares of SEI Investments Company. This represents a change in shares of 17.51% 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)
2026-04-23 2026-03-31 13F SEI INVTS COM 784117103 19,726 2,939 17.51 1,548 12.43 0.0044
2026-02-02 2025-12-31 13F SEI INVTS COM 784117103 16,787 -222 -1.31 1,377 -4.64 0.0169
2025-11-06 2025-09-30 13F SEI INVTS COM 784117103 17,009 -140 -0.82 1,443 -6.36 0.0159
2025-07-31 2025-06-30 13F SEI INVTS COM 784117103 17,149 -439 -2.50 1,541 12.89 0.0177
2025-04-23 2025-03-31 13F SEI INVTS COM 784117103 17,588 -256 -1.43 1,365 -7.21 0.0169
2025-02-05 2024-12-31 13F SEI INVTS COM 784117103 17,844 -138 -0.77 1,472 18.25 0.0179
2024-11-05 2024-09-30 13F SEI INVTS COM 784117103 17,982 768 4.46 1,244 11.77 0.0150
2024-08-08 2024-06-30 13F SEI INVTS COM 784117103 17,214 2,380 16.04 1,114 4.41 0.0142
2024-05-07 2024-03-31 13F SEI INVTS COM 784117103 14,834 -1,366 -8.43 1,067 3.60 0.0156
2024-02-13 2023-12-31 13F SEI INVTS COM 784117103 16,200 -569 -3.39 1,030 1.98 0.0143
2023-11-08 2023-09-30 13F SEI INVTS COM 784117103 16,769 -559 -3.23 1,010 -2.32 0.0155
2023-08-03 2023-06-30 13F SEI INVTS COM 784117103 17,328 -275 -1.56 1,033 1.97 0.0152
2023-05-10 2023-03-31 13F SEI INVTS COM 784117103 17,603 -417 -2.31 1,013 -3.52 0.0156
2023-02-07 2022-12-31 13F SEI INVTS COM 784117103 18,020 1,235 7.36 1,051 27.43 0.0169
2022-11-14 2022-09-30 13F SEI INVTS COM 784117103 16,785 -187 -1.10 824 -10.14 0.0145
2022-08-08 2022-06-30 13F SEI INVTS COM 784117103 16,972 -23,954 -58.53 917 -62.80 0.0154
2022-05-12 2022-03-31 13F SEI INVTS COM 784117103 40,926 -1,167 -2.77 2,465 -3.86 0.0350
2022-02-02 2021-12-31 13F SEI INVTS COM 784117103 42,093 -168 -0.40 2,564 2.31 0.0340
2021-11-12 2021-09-30 13F SEI INVTS COM 784117103 42,261 -925 -2.14 2,506 -6.32 0.0356
2021-08-03 2021-06-30 13F SEI INVTS COM 784117103 43,186 -643 -1.47 2,675 0.19 0.0381
2021-05-17 2021-03-31 13F SEI INVTS COM 784117103 43,829 4,703 12.02 2,670 18.72 0.0414
2021-02-11 2020-12-31 13F SEI INVTS COM 784117103 39,126 24,687 170.97 2,249 207.24 0.0376
2020-11-13 2020-09-30 13F SEI INVTS COM 784117103 14,439 -1,525 -9.55 732 -16.63 0.0142
2020-08-11 2020-06-30 13F SEI INVTS COM 784117103 15,964 -2,500 -13.54 878 2.69 0.0181
2020-05-08 2020-03-31 13F SEI INVESTMENTS COM 784117103 18,464 270 1.48 855 -28.21 0.0210
2020-02-07 2019-12-31 13F SEI INVESTMENTS COM 784117103 18,194 405 2.28 1,191 13.00 0.0252
2019-10-31 2019-09-30 13F SEI INVESTMENTS COM 784117103 17,789 2,153 13.77 1,054 20.18 0.0234
2019-08-09 2019-06-30 13F SEI INVESTMENTS COM 784117103 15,636 -1,285 -7.59 877 -0.79 0.0194
2019-04-24 2019-03-31 13F SEI INVESTMENTS COM 784117103 16,921 9,777 136.86 884 167.88 0.0199
2019-01-30 2018-12-31 13F SEI INVESTMENTS COM 784117103 7,144 130 1.85 330 -22.90 0.0082
2018-10-26 2018-09-30 13F SEI INVESTMENTS COM 784117103 7,014 -578 -7.61 428 -9.70 0.0095
2018-08-10 2018-06-30 13F SEI INVESTMENTS COM 784117103 7,592 -118 -1.53 474 -17.85 0.0116
2018-05-09 2018-03-31 13F SEI INVESTMENTS COM 784117103 7,710 -3,336 -30.20 577 -14.39 0.0145
2018-02-07 2017-12-31 13F SEI INVESTMENTS COM 784117103 11,046 0 0.00 674 0.00 0.0179
2017-11-14 2017-09-30 13F SEI INVESTMENTS COM 784117103 11,046 428 4.03 674 18.04 0.0175
2017-08-09 2017-06-30 13F SEI INVESTMENTS COM 784117103 10,618 -1,228 -10.37 571 -4.36 0.0158
2017-05-15 2017-03-31 13F SEI INVESTMENTS COM 784117103 11,846 11,846 597 0.0170
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.