Regeneron Pharmaceuticals (REGN) director sells 1,500 shares in plan trade

Rhea-AI Filing Summary

Regeneron Pharmaceuticals director Bonnie L. Bassler reported an option exercise and share sale. On January 7, 2026, she exercised 1,500 Non-Qualified Stock Options with an exercise price of $374.12 per share, receiving 1,500 shares of common stock. That same day, she sold 1,500 common shares at a volume-weighted average price of $800.00 per share under a Rule 10b5-1(c) trading plan adopted on May 2, 2025. After these transactions, she directly held 1,703 shares of common stock and 2,861 stock options.

Insider Trade Summary

Net Seller: 1,500 shares ($1,200,000)

Net Sell 3 txns

Insider Bassler Bonnie L

Role Director

Sold 1,500 shs ($1.20M)

Type	Security	Shares	Price	Value
Exercise	Non-Qualified Stock Option (right to buy)	1,500	$0.00	--
Exercise	Common Stock	1,500	$374.12	$561K
Sale	Common Stock	1,500	$800.00	$1.20M

Holdings After Transaction: Non-Qualified Stock Option (right to buy) — 2,861 shares (Direct); Common Stock — 3,203 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. Represents volume-weighted average price of sales of 1,500 shares of Company stock on January 7, 2026 at prices ranging from $800.00 to $800.01. Upon request by the Commission staff, the Company, or a security holder of the Company, the reporting person will provide full information regarding the number of shares sold by the reporting person on January 7, 2026 at each separate price. On the date of the Company'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)
01/07/2026

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	01/07/2026		M(1)		1,500	A	$374.12	3,203	D
Common Stock	01/07/2026		S(1)		1,500	D	$800(2)	1,703	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)	$374.12	01/07/2026		M(1)			1,500	(3)	01/02/2030	Common Stock	1,500	$0.0	2,861	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. Represents volume-weighted average price of sales of 1,500 shares of Company stock on January 7, 2026 at prices ranging from $800.00 to $800.01. Upon request by the Commission staff, the Company, or a security holder of the Company, the reporting person will provide full information regarding the number of shares sold by the reporting person on January 7, 2026 at each separate price.

3. On the date of the Company'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	01/08/2026
	** 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.

FAQ

What insider transactions did REGN director Bonnie L. Bassler report?

Bonnie L. Bassler reported exercising 1,500 Non-Qualified Stock Options at an exercise price of $374.12 per share and selling 1,500 common shares at a volume-weighted average price of $800.00 per share on January 7, 2026.

How many Regeneron (REGN) shares does Bonnie L. Bassler own after this Form 4?

Following the reported transactions, Bonnie L. Bassler directly owned 1,703 shares of Regeneron common stock and 2,861 Non-Qualified Stock Options.

Was Bonnie L. Bassler’s sale of REGN shares under a Rule 10b5-1 plan?

Yes. The filing states the disposition and acquisition were made pursuant to a Rule 10b5-1(c) trading plan adopted on May 2, 2025.

What prices were involved in Bonnie L. Bassler’s REGN transactions?

Her stock options had an exercise price of $374.12 per share, and the 1,500 shares sold on January 7, 2026 had a volume-weighted average sale price of $800.00 per share, within a range of $800.00 to $800.01.

What is Bonnie L. Bassler’s role at Regeneron Pharmaceuticals (REGN)?

The Form 4 identifies Bonnie L. Bassler as a director of Regeneron Pharmaceuticals, Inc.

What derivative security is reported in this Regeneron (REGN) Form 4?

The filing reports a Non-Qualified Stock Option (right to buy) covering 1,500 shares of common stock, with an exercise price of $374.12 and an expiration date of January 2, 2030.