Form 8-K

8-K — SEI INVESTMENTS CO

Accession: 0000350894-26-000033

Filed: 2026-05-28

Period: 2026-05-27

CIK: 0000350894

SIC: 6211 (SECURITY BROKERS, DEALERS & FLOTATION COMPANIES)

Item: Submission of Matters to a Vote of Security Holders

Item: Other Events

Item: Financial Statements and Exhibits

Documents

8-K — seic-20260527.htm (Primary)

EX-99.1 — PRESS RELEASE (exh991seic_dividendx5272.htm)

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8-K — FORM 8-K

8-K (Primary)

Filename: seic-20260527.htm · Sequence: 1

seic-20260527

0000350894FALSE00003508942026-05-272026-05-27

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

________________________________________

FORM 8-K

________________________________________

CURRENT REPORT

PURSUANT TO SECTION 13 OR 15(D)

OF THE SECURITIES EXCHANGE ACT OF 1934

May 27, 2026

Date of report (Date of earliest event reported)

________________________________________

SEI INVESTMENTS COMPANY

(Exact name of registrant as specified in its charter)

Pennsylvania 0-10200 23-1707341

(State or other jurisdiction

of incorporation)

(Commission

File Number) (I.R.S. Employer

Identification No.)

1 Freedom Valley Drive

Oaks, Pennsylvania 19456

(Address of principal executive offices) (Zip Code)

(610) 676-1000

(Registrants’ telephone number, including area code)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below):

☐ Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425).

☐ Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12).

☐ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240-14d-2(b)).

☐ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240-13e-4(c)).

Securities registered pursuant to Section 12(b) of the Act:

Title of each class Trading Symbol Name of each exchange on which registered

Common Stock, par value $0.01 per share SEIC The NASDAQ Stock Market LLC

Indicate by check mark whether the registrant is an emerging growth company as defined in as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. o

Item 5.07. Submission of Matters to a Vote of Security Holders.

On May 27, 2026, at the 2026 Annual Meeting of Shareholders (the “Annual Meeting”) of SEI Investments Company (the “Company”), the following matters were submitted to the shareholders of the Company:

(1)The following nominees were elected as directors of the Company for terms expiring in the year 2029 and received the votes set forth opposite their names below:

Name of Nominee For Against Abstain

Ryan P. Hicke

92,788,771 1,993,774 89,014

Kathryn M. McCarthy

78,056,142 16,743,175 72,242

Thomas C. Naratil

92,377,997 2,410,526 83,036

There were a total of 6,075,123 broker non-votes for the election of directors.

Because the Board of Directors is divided into three classes with one class elected each year to hold office for a three-year term, the term of office for the following directors continued after the Annual Meeting: Jonathan A. Brassington, William M. Doran, Carl A. Guarino, Karin A. Risi, and Carmen V. Romeo.

(2)A resolution to approve, on an advisory basis, the compensation of named executive officers, was approved by 97.5% of the votes cast based on the votes set forth below:

For Against Abstain

92,371,903 2,401,823 97,833

There were a total of 6,075,123 broker non-votes on this matter.

(3) The appointment of KPMG LLP as the independent registered public accountants to examine the Company's consolidated financial statements for 2026 was ratified by 99.4% of the votes cast based on the votes set forth below:

For Against Abstain

100,232,168 627,561 86,953

Item 8.01. Other Events.

On May 27, 2026, the Board of Directors of the Company declared a dividend of $0.52 per share. The cash dividend will be payable to shareholders of record on June 8, 2026, with a payment date of June 16, 2026.

A copy of the press release is furnished as Exhibit 99.1 and incorporated in this Item 8.01 by reference.

Item 9.01. Financial Statements and Exhibits.

(d)Exhibits.

99.1

Press Release of SEI Investments Company dated May 27, 2026

104 Cover Page Interactive Data File (embedded within the Inline XBRL document)

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

SEI Investments Company

Date: May 28, 2026 By: /s/ Sean J. Denham

Sean J. Denham

Chief Financial and Chief Operating Officer

EX-99.1 — PRESS RELEASE

EX-99.1

Filename: exh991seic_dividendx5272.htm · Sequence: 2

exh991seic_dividendx5272

© 2026 SEI® 1 Investor Contact: Media Contact: Brad Burke Alicia Rudd SEI SEI +1 610-676-5350 +1 610-676-3887 bburke2@seic.com arudd@seic.com Pages: 1 FOR IMMEDIATE RELEASE SEI Declares Dividend of $0.52 per Share OAKS, Pa., May 27, 2026 – The Board of Directors of SEI Investments Company (NASDAQ: SEIC) on May 27, 2026 declared a regular semi-annual dividend of $0.52 per share. The cash dividend will be payable to shareholders of record on June 8, 2026, with a payment date of June 16, 2026. About SEI® SEI (NASDAQ:SEIC) is a leading global provider of financial technology, operations, and asset management services within the financial services industry. SEI tailors its solutions and services to help clients more effectively deploy their capital—whether that’s money, time, or talent—so they can better serve their clients and achieve their growth objectives. As of March 31, 2026, SEI manages, advises, or administers approximately $1.9 trillion in assets. For more information, visit seic.com. ### Press release.

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