[Form 4] SEI Investments Co Insider Trading Activity

Rhea-AI Filing Summary

On 07/29/2025, SEI Investments Co. (SEIC) Chief Accounting Officer & Controller Mark Andrew Warner exercised 5,000 employee stock options at an exercise price of $49.63 and immediately sold 5,000 shares of common stock at a weighted-average price of $88.75. After the transactions, Warner’s direct ownership declined from 6,300 to 1,300 shares. The exercised options, granted in 2017 and 2019 and expiring 12/13/2026, are now fully exhausted, leaving the officer with no remaining derivative securities. The filing, submitted on 07/30/2025, was made on behalf of a single reporting person and does not reference a Rule 10b5-1 trading plan.

Positive

• None.

Negative

• Senior officer sold 5,000 shares, reducing direct ownership to 1,300, which may signal diminished personal stake.
• No remaining derivative securities held after option exercises, limiting future equity alignment.

Insights

Financial Analyst

TL;DR: Officer converted options then sold all exercised shares, cutting direct stake to 1,300; ~90% of exercised stock monetised.

The CAO’s sale represents roughly $445k in proceeds (5,000 × $88.75) and a ~$195k intrinsic gain over the $49.63 strike. Because the officer retained only 1,300 shares, investors may view the move as de-risking personal exposure ahead of option expiry rather than a long-term confidence signal. With no derivatives left, Warner’s future equity alignment is now limited to the residual holding. While the transaction is modest relative to SEI’s $11 bn market cap, insider disposition by a senior accounting executive can weigh on sentiment, especially absent a pre-arranged 10b5-1 plan.

SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0287
Estimated average burden
hours per response:			0.5

Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

Warner Mark Andrew

(Last) (First) (Middle)

1 FREEDOM VALLEY DRIVE

(Street)

OAKS PA 19456

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
SEI INVESTMENTS CO [ SEIC ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

	Director		10% Owner
	Officer (give title below)	X	Other (specify below)
			See Remarks

3. Date of Earliest Transaction (Month/Day/Year)
07/29/2025

4. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Stock	07/29/2025		M		5,000	A	$49.63	6,300	D
Common Stock	07/29/2025		S		5,000	D	$88.75(1)	1,300	D

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
STOCK OPTION RIGHT TO PURCHASE	$49.63	07/29/2025		M			2,500	12/31/2017	12/13/2026	Common Stock	2,500	(2)	0	D
STOCK OPTION RIGHT TO PURCHASE	$49.63	07/29/2025		M			2,500	12/31/2019	12/13/2026	Common Stock	2,500	(2)	0	D

Explanation of Responses:

1. Represents the weighted average of a range of sale prices from $88.61 to $89.24. 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.

2. Received as employment compensation

Remarks:

Title: Chief Accounting Officer and Controller

	/s/Mark Andrew Warner, by Diane Gallagher, attorney in fact	07/30/2025
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.

FAQ

How many SEIC shares did the officer sell?

Mark Andrew Warner sold 5,000 SEIC common shares on 07/29/2025.

At what price were the SEIC shares sold?

The weighted-average sale price was $88.75 per share (range $88.61–$89.24).

What is the officer's remaining SEIC share ownership?

After the transactions, Warner directly owns 1,300 SEIC shares.

Were the sales made under a Rule 10b5-1 plan?

The Form 4 does not indicate that the transactions were executed under a Rule 10b5-1 plan.

What was the exercise price of the stock options?

Both option tranches were exercised at $49.63 per share.

How many stock options remain with the officer?

Following the exercises, the officer holds zero derivative securities.