BlackRock, Inc. ownership in SEIC / SEI Investments Company

SEI Investments Company

US ˙ NasdaqGS ˙ US7841171033

Security	SEIC / SEI Investments Company
Institution	BlackRock, Inc.
Latest Disclosed Ownership	8,492,433 shares
Ownership	6.80%

2025-07-16 - BlackRock, Inc. has filed an SCHEDULE 13G/A form with the Securities and Exchange Commission (SEC) disclosing ownership of 8,492,433 shares of SEI Investments Company (US:SEIC). This represents 6.8 percent ownership of the company. In their previous filing dated 2024-01-25 , BlackRock, Inc. had reported owning 11,162,525 shares, indicating a decrease of -23.92 percent.

Institutional Ownership: 13D/G Filings

This table shows a history of the 13D/G filings made by the investor and/or investor group. Note that the share values in this table are not directly comparable to any numbers shown in the 13F table (if any).

File Date	Effective Date	Form	Prev Shares	Latest Shares	ΔShares (Percent)	Ownership (Percent)	ΔOwnership (Percent)
2025-07-16	2025-07-16	13G/A	11,162,525	8,492,433	-23.92	6.80	-20.00
2024-01-25	2024-01-25	13G/A	11,458,899	11,162,525	-2.59	8.50	0.00
2023-02-03	2023-02-03	13G/A	11,385,537	11,458,899	0.64	8.50	3.66
2022-02-07	2022-02-07	13G/A	12,580,487	11,385,537	-9.50	8.20	-5.75
2021-02-01	2021-02-01	13G/A	14,041,605	12,580,487	-10.41	8.70	-6.45
2020-02-06	2020-02-06	13G/A	14,153,322	14,041,605	-0.79	9.30	2.20
2019-02-06	2019-02-06	13G/A	13,949,844	14,153,322	1.46	9.10	2.25
2018-01-23	2018-01-23	13G/A	11,820,981	13,949,844	18.01	8.90	20.27
2017-01-27	2017-01-27	13G/A	11,820,981	11,820,981	0.00	7.40	0.00
2017-01-26	2017-01-26	13G/A	11,154,009	11,820,981	5.98	7.40	8.82
2016-01-27	2016-01-27	13G/A		11,154,009		6.80
2015-01-30	2015-01-30	13G/A		10,488,306		6.30
2014-01-30	2014-01-30	13G		10,926,391		6.40

Important Note: One of the primary uses of the 13D/G filings is to evaluate the ability of a firm to control a company (ie, the "beneficial ownership"). To that end, firms are required to report not just direct holdings in companies, but indirect holdings that they control. For investment firms, these indirect holdings can include shares in funds they manage, advisory accounts, and in the case of activist campaigns, pledged votes. Therefore, share counts listed in 13D/G filings can differ significantly than share counts listed in 13F filings.

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	Reported Shares	ΔShares	ΔShares (%)	Reported Value (x1000)	ΔValue (%)	Alloc (%)
2026-05-13	2026-03-31	13F	SEI INVTS	COM	784117103	10,110,337	472,497	4.90	793,358	0.36	0.0010
2026-02-12	2025-12-31	13F	SEI INVTS	COM	784117103	9,637,840	375,238	4.05	790,496	0.58	0.0134
2025-11-12	2025-09-30	13F	SEI INVTS	COM	784117103	9,262,602	60,582	0.66	785,932	-4.95	0.0138
2025-08-12	2025-06-30	13F	SEI INVTS	COM	784117103	9,202,020	-2,168,392	-19.07	826,894	-6.32	0.0157
2025-05-02	2025-03-31	13F	SEI INVTS	COM	784117103	11,370,412	-132,245	-1.15	882,685	-6.96	0.0185
2025-02-07	2024-12-31	13F	SEI INVTS	COM	784117103	11,502,657	92,569	0.81	948,739	20.18	0.0192
2024-11-13	2024-09-30	13F	SEI INVTS	COM	784117103	11,410,088	-83,355	-0.73	789,464	6.18	0.0166
2024-08-13	2024-06-30	13F	SEI INVTS	COM	784117103	11,493,443	-221,137	-1.89	743,511	-11.73	0.0168
2024-05-10	2024-03-31	13F	SEI INVTS	COM	784117103	11,714,580	551,844	4.94	842,278	18.73	0.0196
2024-02-13	2023-12-31	13F	SEI INVTS	COM	784117103	11,162,736	-197,206	-1.74	709,392	3.68	0.0181
2023-11-13	2023-09-30	13F	SEI INVTS	COM	784117103	11,359,942	158,281	1.41	684,209	2.45	0.0197
2023-08-11	2023-06-30	13F	SEI INVTS	COM	784117103	11,201,661	-569,059	-4.83	667,843	-1.41	0.0184
2023-05-12	2023-03-31	13F	SEI INVTS	COM	784117103	11,770,720	311,552	2.72	677,405	1.40	0.0200
2023-02-13	2022-12-31	13F	SEI INVTS	COM	784117103	11,459,168	-25,678	-0.22	668,069	18.59	0.0209
2022-11-14	2022-09-30	13F	SEI INVTS	COM	784117103	11,484,846	-169,876	-1.46	563,332	-10.52	0.0192
2022-08-12	2022-06-30	13F	SEI INVTS	COM	784117103	11,654,722	8,768	0.08	629,589	-10.21	0.0202
2022-05-12	2022-03-31	13F	SEI INVTS	COM	784117103	11,645,954	260,417	2.29	701,203	1.06	0.0189
2022-02-10	2021-12-31	13F	SEI INVTS	COM	784117103	11,385,537	6,440	0.06	693,837	2.82	0.0177
2021-11-09	2021-09-30	13F	SEI INVTS	COM	784117103	11,379,097	-691,178	-5.73	674,779	-9.79	0.0189
2021-08-11	2021-06-30	13F	SEI INVTS	COM	784117103	12,070,275	-671,112	-5.27	747,994	-3.65	0.0208
2021-05-07	2021-03-31	13F	SEI INVTS	COM	784117103	12,741,387	160,900	1.28	776,335	7.38	0.0228
2021-02-05	2020-12-31	13F	SEI INVTS	COM	784117103	12,580,487	-218,808	-1.71	723,002	11.37	0.0231
2020-11-06	2020-09-30	13F	SEI INVTS	COM	784117103	12,799,295	-283,946	-2.17	649,181	-9.75	0.0240
2020-08-14	2020-06-30	13F	SEI INVTS	COM	784117103	13,083,241	-711,203	-5.16	719,317	12.53	0.0287
2020-05-01	2020-03-31	13F	SEI INVESTMENTS	COM	784117103	13,794,444	-247,161	-1.76	639,235	-30.48	0.0313
2020-02-13	2019-12-31	13F	SEI INVESTMENTS	COM	784117103	14,041,605	301,789	2.20	919,444	12.93	0.0353
2019-11-08	2019-09-30	13F	SEI INVESTMENTS	COM	784117103	13,739,816	-211,091	-1.51	814,152	4.03	0.0342
2019-08-22	2019-06-30	13F/A-1	SEI INVESTMENTS	COM	784117103	13,950,907	165,595	1.20	782,645	8.66	0.0335
2019-08-13	2019-06-30	13F	SEI INVESTMENTS	COM	784117103	13,950,907	165,595		782,645
2019-05-09	2019-03-31	13F	SEI INVESTMENTS	COM	784117103	13,785,312	-368,010	-2.60	720,283	10.15	0.0322
2019-02-08	2018-12-31	13F	SEI INVESTMENTS	COM	784117103	14,153,322	282,606	2.04	653,883	-22.85	0.0330
2018-11-09	2018-09-30	13F	SEI INVESTMENTS	COM	784117103	13,870,716	485,625	3.63	847,500	1.27	0.0367
2018-08-09	2018-06-30	13F	SEI INVESTMENTS	COM	784117103	13,385,091	298,517	2.28	836,835	-14.64	0.0386
2018-05-09	2018-03-31	13F	SEI INVESTMENTS	COM	784117103	13,086,574	-863,270	-6.19	980,314	-2.21	0.0469
2018-02-09	2017-12-31	13F	SEI INVESTMENTS	COM	784117103	13,949,844	254,860	1.86	1,002,436	19.88	0.0477
2017-11-14	2017-09-30	13F	SEI INVESTMENTS	COM	784117103	13,694,984	247,130	1.84	836,216	15.62	0.0422
2017-08-10	2017-06-30	13F	SEI INVESTMENTS	COM	784117103	13,447,854	697,125	5.47	723,225	12.45	0.0384
2017-05-12	2017-03-31	13F	SEI INVESTMENTS	COM	784117103	12,750,729	12,410,221	3,644.62	643,148	3,726.67	0.0353
2017-02-10	2016-12-31	13F	SEI INVESTMENTS	COM	784117103	340,508	-82,983	-19.59	16,807	-12.98	0.0238
2016-11-08	2016-09-30	13F	SEI INVESTMENTS	COM	784117103	423,491	-4,750	-1.11	19,315	-6.25	0.0277
2016-08-10	2016-06-30	13F	SEI INVESTMENTS	COM	784117103	428,241	66,128	18.26	20,603	32.16	0.0310
2016-05-10	2016-03-31	13F	SEI INVESTMENTS	COM	784117103	362,113	5,667	1.59	15,589	-16.54	0.0251
2016-02-11	2015-12-31	13F	SEI INVESTMENTS	COM	784117103	356,446	-10,531	-2.87	18,678	5.53	0.0274
2015-11-13	2015-09-30	13F	SEI INVESTMENTS	COM	784117103	366,977	-42,170	-10.31	17,700	-11.77	0.0277
2015-08-07	2015-06-30	13F	SEI INVESTMENTS	COM	784117103	409,147	-72,391	-15.03	20,061	-5.51	0.0297
2015-05-13	2015-03-31	13F	SEI INVESTMENTS	COM	784117103	481,538	37,538	8.45	21,230	19.42	0.0293
2015-02-09	2014-12-31	13F	SEI INVESTMENTS	COM	784117103	444,000	69,687	18.62	17,777	31.33	0.0254
2014-10-29	2014-09-30	13F	SEI INVESTMENTS	COM	784117103	374,313	888	0.24	13,536	10.62	0.0198
2014-08-06	2014-06-30	13F	SEI INVESTMENTS	COM	784117103	373,425	10,169	2.80	12,237	0.24	0.0182
2014-05-02	2014-03-31	13F	SEI INVESTMENTS	COM	784117103	363,256	-36,327	-9.09	12,208	-12.03	0.0197
2014-02-12	2013-12-31	13F	SEI INVESTMENTS	COM	784117103	399,583	14,426	3.75	13,877	16.55	0.0227
2013-11-12	2013-09-30	13F	SEI INVESTMENTS	COM	784117103	385,157	191,480	98.87	11,906	116.24	0.0224
2013-08-13	2013-06-30	13F	SEI INVESTMENTS	COM	784117103	193,677	193,677		5,506		0.0109

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.