Michael Peterson - 28 Aug 2026 Form 4 Insider Report for SEI INVESTMENTS CO (SEIC)

Reporting relationship: Executive Vice President
Issuer ticker: SEIC
Reported as of: 28 Aug 2026
Net transaction value: -$4,181,625
SEC form: 4
Accepted by SEC: 01 Sep 2026, 16:05:59 UTC
Prior SEC filing: 30 Jul 2026
Source filing: View source filing
Reporting owner signature: /s/ Michael Peterson by Lindsay A. Barci, attorney in fact

Key filing fact

Michael Peterson filed Form 4 for SEI INVESTMENTS CO (SEIC) on 01 Sep 2026.

Key facts

This page summarizes Michael Peterson's Form 4 filing for SEI INVESTMENTS CO (SEIC).
3 reported transactions and 1 derivative row are listed below.
Accepted by SEC: 01 Sep 2026, 16:05.

Change

Previous filing in this sequence was filed on 30 Jul 2026.
Current net transaction value: -$4,181,625.

Research use

This tells you what this filing adds before you inspect full transaction and derivative tables.
You can trace every row back to the original SEC filing document.

Evidence

Filed on Form 4

Ownership activity is grounded in SEC Form 4 disclosures.

View source filing

Reporting Owners (1)

CIK 0001745371 Primary reporting owner

Peterson Michael

Relationship: Executive Vice President
Address: 1 FREEDOM VALLEY DRIVE, OAKS
Signature: /s/ Michael Peterson by Lindsay A. Barci, attorney in fact
Signature date: 01 Sep 2026

Reported non-derivative transactions

Shares, units, or other non-derivative securities reported in this filing.

SEIC transaction

Common Stock

Options Exercise

Transaction value
Shares: +37,500
Change %: +186%
Price: $56.54^*
Shares after: 57,648
Date: 28 Aug 2026
Ownership: Direct

SEIC transaction

Common Stock

Sale

Transaction value: $4,181,625
Shares: -37,500
Change %: -65%
Price: $111.51
Shares after: 20,148
Date: 28 Aug 2026
Ownership: Direct
Footnotes: F1

SEIC holding

Common Stock

No transaction description listed

Transaction value
Shares
Change %
Price
Shares after: 454
Date: 28 Aug 2026
Ownership: By Employee Stock Purchase Plan
Footnotes: F2

Reported derivative securities

Options, warrants, convertible securities, or similar derivative positions disclosed in the filing.

SEIC transaction Derivative

Option to Purchase Common Stock

Options Exercise

Transaction value
Shares: -37,500
Change %: -100%
Price
Shares after: 0
Date: 28 Aug 2026
Ownership: Direct
Underlying class: Common Stock
Underlying amount: 37,500
Exercise price: $56.54
Footnotes: F3

^* marks a reported price that did not pass the local price check.

Additional SEC filing notes

Filing notes and footnotes

Explanation of responses 3 footnotes

Footnote F1

Represents the weighted average of a range of sale prices from $111.19 to $112.07. The reporting person undertakes to provide to the Staff of the Securities and Exchange Commission, the Company, or any stockholder of the Company, upon request, full information regarding the number of shares sold at each separate price.

Footnote F2

Reflects the addition of approximately 91 shares purchased by the Reporting Person through the Company's Employee Stock Purchase Plan.

Footnote F3

Received as employment compensation.