SEI Investments (SEIC) director sells 10,000 shares after option exercise

Rhea-AI Filing Summary

SEI Investments director Kathryn McCarthy reported an exercise-and-sell transaction involving company common stock. On May 4, 2026, she sold 10,000 shares of SEI Investments common stock in an open-market sale at a weighted-average price of $91.07 per share, with individual prices ranging from $91.00 to $91.23.

On the same date, she exercised stock options to acquire a total of 10,000 shares of common stock at an exercise price of $49.63 per share, received as compensation for service on the company’s Board of Directors. After these transactions, she directly owned 77,883 shares of SEI Investments common stock, with no remaining derivative position from the exercised options.

Insider Trade Summary

Net Seller: 10,000 shares ($910,700)

Net Sell 5 txns

Insider MCCARTHY KATHRYN

Role null

Sold 10,000 shs ($911K)

Type	Security	Shares	Price	Value
Exercise	STOCK OPTION (RIGHT TO PURCHASE)	5,000	$0.00	--
Exercise	STOCK OPTION (RIGHT TO PURCHASE)	5,000	$0.00	--
Exercise	Common Stock	5,000	$49.63	$248K
Exercise	Common Stock	5,000	$49.63	$248K
Sale	Common Stock	10,000	$91.07	$911K

Holdings After Transaction: STOCK OPTION (RIGHT TO PURCHASE) — 0 shares (Direct, null); Common Stock — 82,883 shares (Direct, null)

Footnotes (1)

1. Represents the weighted average of a range of sale prices from $91.00 to $91.23. 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. Received as compensation for service on the Company's Board of Directors.

Key Figures

Shares sold: 10,000 shares Sale price: $91.07 per share Options exercised: 10,000 shares +3 more

6 metrics

Shares sold 10,000 shares Open-market sale of common stock on May 4, 2026

Sale price $91.07 per share Weighted-average sale price; trades from $91.00 to $91.23

Options exercised 10,000 shares Common stock acquired through option exercises on May 4, 2026

Exercise price $49.63 per share Exercise price of stock options converted into common stock

Shares owned after 77,883 shares Direct holdings of SEI Investments common stock after transactions

Net buy/sell shares -10,000 shares Net share change from reported buy/sell activity

Key Terms

open-market sale, stock option (right to purchase), weighted average, derivative exercise/conversion, +1 more

5 terms

open-market sale financial

"she sold 10,000 shares of SEI Investments common stock in an open-market sale"

An open-market sale is when a shareholder sells existing shares directly on a public exchange to any willing buyer, rather than through a private deal. Think of it like putting goods on a busy market stall where price is set by supply and demand; for investors it matters because such sales increase available supply, can put short-term downward pressure on the stock price, and signal changes in liquidity or investor confidence.

stock option (right to purchase) financial

"STOCK OPTION (RIGHT TO PURCHASE) covering 10,000 underlying common shares"

weighted average financial

"Represents the weighted average of a range of sale prices from $91.00 to $91.23"

A weighted average is a way of calculating an overall number when some items matter more than others by giving each item a different level of importance, or weight. Investors use weighted averages to combine figures like prices, returns or earnings so the result reflects the size or significance of each part — like grading a class where a final exam counts more than a quiz, producing a score that better represents true performance.

derivative exercise/conversion financial

"transaction_action is classified as a derivative exercise/conversion"

compensation for service on the Company's Board of Directors financial

"Received as compensation for service on the Company's Board of Directors"

Form 4 Insider Transactions: What Each Field Means →

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^*

MCCARTHY KATHRYN

(Last) (First) (Middle)

ONE FREEDOM VALLEY DRIVE

(Street)

OAKS PENNSYLVANIA 19456

(City) (State) (Zip)

UNITED STATES

(Country)

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

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

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

2a. Foreign Trading Symbol

3. Date of Earliest Transaction (Month/Day/Year)
05/04/2026

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

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

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

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	05/04/2026		M		5,000	A	$49.63	82,883	D
Common Stock	05/04/2026		M		5,000	A	$49.63	87,883	D
Common Stock	05/04/2026		S		10,000	D	$91.07(1)	77,883	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	05/04/2026		M			5,000	12/31/2017	12/13/2026	Common Stock	5,000	(2)	0	D
STOCK OPTION (RIGHT TO PURCHASE)	$49.63	05/04/2026		M			5,000	12/31/2019	12/13/2026	Common Stock	5,000	(2)	0	D

Explanation of Responses:

1. Represents the weighted average of a range of sale prices from $91.00 to $91.23. 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 compensation for service on the Company's Board of Directors.

Remarks:

	/s/ Kathryn McCarthy, by Diane Gallagher, attorney in fact	05/05/2026
	** 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.
* Form 4: SEC 1474 (03-26)

FAQ

What insider transactions did SEIC director Kathryn McCarthy report?

Director Kathryn McCarthy reported selling 10,000 shares of SEI Investments common stock and exercising options for 10,000 shares. These actions occurred on May 4, 2026, and are recorded as open-market sales and derivative exercises in the Form 4 filing.

At what prices did Kathryn McCarthy trade SEI Investments (SEIC) shares?

McCarthy’s 10,000-share sale used a weighted-average price of $91.07 per share, with individual sale prices between $91.00 and $91.23. She exercised stock options for 10,000 shares at an exercise price of $49.63 per share on the same date.

How many SEI Investments (SEIC) shares does Kathryn McCarthy hold after these trades?

Following the reported transactions, Kathryn McCarthy directly holds 77,883 shares of SEI Investments common stock. This post-transaction figure reflects her remaining equity stake after selling 10,000 shares and exercising options for 10,000 additional shares.

What type of options did Kathryn McCarthy exercise in SEI Investments (SEIC)?

She exercised stock options described as a “STOCK OPTION (RIGHT TO PURCHASE)” covering 10,000 underlying common shares in total. These options had an exercise price of $49.63 per share and were received as compensation for serving on SEI’s Board of Directors.

Was Kathryn McCarthy’s SEIC stock sale a routine open-market transaction?

The filing classifies the 10,000-share disposition as an open-market sale under transaction code “S.” A footnote states the price shown is a weighted average for trades executed between $91.00 and $91.23 per share, consistent with typical market transactions.