REGN Form 4: Director exercises options, reports 760-share sale

Rhea-AI Filing Summary

Regeneron Pharmaceuticals (REGN) director reports stock option exercise and sale. On 11/20/2025, the reporting person exercised a non-qualified stock option for 760 shares of common stock at an exercise price of $371.4 per share and then sold 760 shares of common stock at a price of $750 per share. After these transactions, the director beneficially owned 1,548 shares of Regeneron common stock directly and 756 non-qualified stock options. The transactions were made under a Rule 10b5-1(c) trading plan adopted on May 2, 2025.

Insider Trade Summary

Net Seller: 760 shares ($570,000)

Net Sell 3 txns

Insider Bassler Bonnie L

Role Director

Sold 760 shs ($570K)

Type	Security	Shares	Price	Value
Exercise	Non-Qualified Stock Option (right to buy)	760	$0.00	--
Exercise	Common Stock	760	$371.40	$282K
Sale	Common Stock	760	$750.00	$570K

Holdings After Transaction: Non-Qualified Stock Option (right to buy) — 756 shares (Direct); Common Stock — 2,308 shares (Direct)

Footnotes (1)

1. Disposition/acquisition made pursuant to a plan intended to comply with Rule 10b5-1(c) adopted on May 2, 2025. On the date of the Issuer's first annual meeting of shareholders following the date of grant, a portion of these stock options equal to the portion of one year that had passed from the date of grant became exercisable, and the remainder became exercisable on the first anniversary of the date of grant.

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).

X

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^*

Bassler Bonnie L

(Last) (First) (Middle)

777 OLD SAW MILL RIVER ROAD

(Street)

TARRYTOWN NY 10591

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
REGENERON PHARMACEUTICALS, INC. [ REGN ]

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

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

3. Date of Earliest Transaction (Month/Day/Year)
11/20/2025

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	11/20/2025		M(1)		760	A	$371.4	2,308	D
Common Stock	11/20/2025		S(1)		760	D	$750	1,548	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
Non-Qualified Stock Option (right to buy)	$371.4	11/20/2025		M(1)			760	(2)	01/02/2029	Common Stock	760	$0.0	756	D

Explanation of Responses:

1. Disposition/acquisition made pursuant to a plan intended to comply with Rule 10b5-1(c) adopted on May 2, 2025.

2. On the date of the Issuer's first annual meeting of shareholders following the date of grant, a portion of these stock options equal to the portion of one year that had passed from the date of grant became exercisable, and the remainder became exercisable on the first anniversary of the date of grant.

	/s/ Bonnie L. Bassler	11/24/2025
	** 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

What insider transaction did REGN disclose in this Form 4?

The filing reports that a Regeneron Pharmaceuticals (REGN) director exercised a non-qualified stock option for 760 shares at $371.4 per share and sold 760 shares of common stock at $750 per share on 11/20/2025.

How many REGN shares does the director own after the reported transaction?

Following the reported trades, the director beneficially owned 1,548 shares of Regeneron common stock directly and held 756 non-qualified stock options.

Was the REGN insider trade made under a Rule 10b5-1 plan?

Yes. The exercise and sale were made pursuant to a Rule 10b5-1(c) trading plan that was adopted on May 2, 2025.

What type of derivative security did the REGN director exercise?

The director exercised a non-qualified stock option (right to buy) for 760 shares of Regeneron common stock at an exercise price of $371.4 per share.

What were the sale details of REGN shares reported in this Form 4?

On 11/20/2025, the director sold 760 shares of Regeneron common stock at a price of $750 per share, as disclosed in Table I of the filing.

What is the relationship of the reporting person to Regeneron Pharmaceuticals (REGN)?

The reporting person is listed as a Director of Regeneron Pharmaceuticals, Inc. (REGN) and filed the Form 4 as an individual reporting person.