SEI 투자 회사
MX ˙ BMV ˙ US7841171033
SecurityMX:SEIC / SEI Investments Company
InstitutionNatixis Advisors, L.p.
Latest Disclosed Ownership469,864 shares
Latest Disclosed Value $ 36,870
Natixis Advisors, L.p. reports 0.13% decrease in ownership of SEIC / SEI Investments Company

On May 13, 2026 - Natixis Advisors, L.p. filed a 13F-HR form disclosing ownership of 469,864 shares of SEI Investments Company (MX:SEIC) valued at $36,870 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 10, 2026 disclosing 470,476 shares of SEI Investments Company. This represents a change in shares of -0.13% 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.

Upgrade to unlock premium data and export to Excel .

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)
2026-05-13 2026-03-31 13F SEI INVESTMENTS COM 784117103 469,864 -612 -0.13 37 -5.26 0.0513
2026-02-10 2025-12-31 13F SEI INVESTMENTS COM 784117103 470,476 -40,590 -7.94 39 -11.63 0.0547
2025-11-13 2025-09-30 13F SEI INVESTMENTS COM 784117103 511,066 -18,568 -3.51 43 -8.51 0.0633
2025-08-13 2025-06-30 13F SEI INVESTMENTS COM 784117103 529,634 -8,830 -1.64 48 14.63 0.0755
2025-05-08 2025-03-31 13F SEI INVESTMENTS COM 784117103 538,464 -10,182 -1.86 42 -8.89 0.0772
2025-02-10 2024-12-31 13F SEI INVTS COM 784117103 548,646 -125,624 -18.63 45 -2.17 0.0846
2024-11-06 2024-09-30 13F SEI INVESTMENTS COM 784117103 674,270 -1,005 -0.15 47 6.98 0.0910
2024-08-01 2024-06-30 13F SEI INVESTMENTS COM 784117103 675,275 -3,054 -0.45 44 -10.42 0.0950
2024-04-25 2024-03-31 13F SEI INVESTMENTS COM 784117103 678,329 1,795 0.27 49 14.29 0.1121
2024-02-06 2023-12-31 13F SEI INVESTMENTS COM 784117103 676,534 -27,476 -3.90 43 0.00 0.1132
2023-11-13 2023-09-30 13F SEI INVESTMENTS COM 784117103 704,010 -32,675 -4.44 42 -2.33 0.1297
2023-08-15 2023-06-30 13F SEI INVESTMENTS COM 784117103 736,685 -17,336 -2.30 44 0.00 0.1356
2023-05-11 2023-03-31 13F SEI INVESTMENTS COM 784117103 754,021 2,502 0.33 43 0.00 0.1493
2023-01-27 2022-12-31 13F SEI INVESTMENTS COM 784117103 751,519 -36,356 -4.61 44 -99.89 0.1656
2022-11-14 2022-09-30 13F SEI INVESTMENTS COM 784117103 787,875 -20,195 -2.50 38,645 -11.47 0.1635
2022-08-12 2022-06-30 13F SEI INVESTMENTS COM 784117103 808,070 -5,788 -0.71 43,651 -10.92 0.1920
2022-05-12 2022-03-31 13F SEI INVESTMENTS COM 784117103 813,858 -37,196 -4.37 49,002 -5.52 0.1869
2022-02-08 2021-12-31 13F SEI INVESTMENTS COM 784117103 851,054 -370,061 -30.31 51,863 -28.38 0.1980
2021-11-15 2021-09-30 13F SEI INVESTMENTS COM 784117103 1,221,115 565,186 86.17 72,411 78.15 0.2978
2021-08-12 2021-06-30 13F SEI INVTS COM 784117103 655,929 -11,443 -1.71 40,647 -0.03 0.1897
2021-05-05 2021-03-31 13F SEI INVTS COM 784117103 667,372 10,602 1.61 40,661 7.73 0.2122
2021-02-12 2020-12-31 13F SEI INVTS COM 784117103 656,770 -240,542 -26.81 37,745 -17.06 0.2174
2020-11-12 2020-09-30 13F SEI INVTS COM 784117103 897,312 -27,555 -2.98 45,511 -10.50 0.2864
2020-08-11 2020-06-30 13F SEI INVTS COM 784117103 924,867 14,266 1.57 50,849 20.50 0.3375
2020-04-27 2020-03-31 13F SEI INVESTMENTS COM 784117103 910,601 -17,717 -1.91 42,197 -30.58 0.3439
2020-02-10 2019-12-31 13F SEI INVESTMENTS COM 784117103 928,318 -24,236 -2.54 60,786 7.69 0.4287
2019-11-12 2019-09-30 13F SEI INVESTMENTS COM 784117103 952,554 -51,391 -5.12 56,443 0.22 0.4480
2019-08-12 2019-06-30 13F SEI INVESTMENTS COM 784117103 1,003,945 -30,226 -2.92 56,321 4.23 0.4600
2019-05-15 2019-03-31 13F/A-1 SEI INVESTMENTS COM 784117103 1,034,171 108,285 11.70 54,036 26.32 0.4731
2019-05-15 2019-03-31 13F SEI INVESTMENTS COM 784117103 1,034,171 108,285 54,036
2019-02-13 2018-12-31 13F/A-1 SEI INVESTMENTS COM 784117103 925,886 -118,122 -11.31 42,776 -32.94 0.4223
2019-02-13 2018-12-31 13F SEI INVESTMENTS COM 784117103 925,886 -118,122 42,776
2018-11-13 2018-09-30 13F SEI INVESTMENTS COM 784117103 1,044,008 76,567 7.91 63,788 5.46 0.5615
2018-08-14 2018-06-30 13F/A-1 SEI INVESTMENTS COM 784117103 967,441 -66,207 -6.41 60,484 -21.89 0.5778
2018-08-14 2018-06-30 13F SEI INVESTMENTS COM 784117103 967,441 60,484
2018-05-10 2018-03-31 13F SEI INVESTMENTS COM 784117103 1,033,648 -15,897 -1.51 77,430 2.67 0.7642
2018-02-14 2017-12-31 13F SEI INVESTMENTS COM 784117103 1,049,545 -29,128 -2.70 75,420 14.51 0.7682
2017-11-14 2017-09-30 13F SEI INVESTMENTS COM 784117103 1,078,673 -36,313 -3.26 65,862 9.84 0.6958
2017-07-27 2017-06-30 13F SEI INVESTMENTS COM 784117103 1,114,986 18,850 1.72 59,964 8.46 0.6490
2017-05-12 2017-03-31 13F SEI INVESTMENTS COM 784117103 1,096,136 173,819 18.85 55,289 21.44 0.6126
2017-02-07 2016-12-31 13F SEI INVESTMENTS COM 784117103 922,317 108,482 13.33 45,526 22.65 0.5474
2016-11-04 2016-09-30 13F SEI INVESTMENTS COM 784117103 813,835 46,698 6.09 37,119 0.57 0.4808
2016-08-01 2016-06-30 13F SEI INVESTMENTS COM 784117103 767,137 33,984 4.64 36,907 16.93 0.5102
2016-05-06 2016-03-31 13F SEI INVESTMENTS COM 784117103 733,153 25,368 3.58 31,562 -14.90 0.4723
2016-02-12 2015-12-31 13F SEI INVESTMENTS COM 784117103 707,785 22,858 3.34 37,088 12.27 0.6080
2015-11-12 2015-09-30 13F SEI INVESTMENTS COM 784117103 684,927 80,586 13.33 33,034 11.49 0.5730
2015-08-14 2015-06-30 13F SEI INVESTMENTS COM 784117103 604,341 61,341 11.30 29,630 23.76 0.5031
2015-05-15 2015-03-31 13F SEI INVESTMENTS COM 784117103 543,000 95,927 21.46 23,941 33.74 0.4202
2015-02-05 2014-12-31 13F SEI INVESTMENTS COM 784117103 447,073 51,819 13.11 17,901 25.26 0.3350
2014-11-03 2014-09-30 13F SEI INVESTMENTS COM 784117103 395,254 -341,400 -46.34 14,291 -40.80 0.2868
2014-08-13 2014-06-30 13F SEI INVESTMENTS COM 784117103 736,654 64,861 9.65 24,140 6.91 0.3459
2014-05-13 2014-03-31 13F SEI INVESTMENTS COM 784117103 671,793 8,978 1.35 22,579 -1.91 0.3475
2014-02-12 2013-12-31 13F SEI INVESTMENTS COM 784117103 662,815 42,819 6.91 23,019 20.12 0.3768
2013-10-30 2013-09-30 13F SEI INVESTMENTS COM 784117103 619,996 75,933 13.96 19,164 23.90 0.3529
2013-07-19 2013-06-30 13F SEI INVESTMENTS COM 784117103 544,063 544,063 15,467 0.3081
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.