STOCK TITAN

Regeneron (REGN) director Kathryn Guarini exercises 400 options, sells 400 shares

(Neutral)
(Neutral)
Form Type
4

Rhea-AI Filing Summary

REGENERON PHARMACEUTICALS, INC. director Kathryn Guarini exercised 400 non-qualified stock options for Common Stock at an exercise price of $719.37 per share on August 10, 2026, leaving 1,558 options outstanding that expire on January 2, 2035.

The 400 acquired shares were then sold at $800.00 per share the same day. The disposition and acquisition were made pursuant to a Rule 10b5-1(c) trading plan adopted on February 13, 2026.

Positive

  • None.

Negative

  • None.
Insider Guarini Kathryn
Role Director
Sold 400 shs ($320K)
Approx. gross sale proceeds $320K
Approx. exercise cost $288K
Approx. pre-tax spread $32K
Type Security Shares Price Value
Exercise Non-Qualified Stock Option (right to buy) F1, F2 400 $0.00 $0.00
Exercise Common Stock F1 400 $719.37 $288K
Sale Common Stock F1 400 $800.00 $320K
Holdings After Transaction: Non-Qualified Stock Option (right to buy) — 1,558 shares (Direct); Common Stock — 603 shares (Direct)
Footnotes (2)
  1. F1. Disposition/acquisition made pursuant to a plan intended to comply with Rule 10b5-1(c) adopted on February 13, 2026.
  2. F2. 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.
Options exercised 400 shares Non-Qualified Stock Options exercised on August 10, 2026
Exercise price $719.37 per share Exercise price of Non-Qualified Stock Options for Common Stock
Shares sold 400 shares Common Stock sale on August 10, 2026 following option exercise
Sale price $800.00 per share Price for sale of 400 shares of Common Stock
Options remaining 1,558 options Non-Qualified Stock Options outstanding after the exercise
Option expiration January 2, 2035 Expiration date of the Non-Qualified Stock Options
10b5-1 plan adoption date February 13, 2026 Date the Rule 10b5-1(c) trading plan was adopted
Non-Qualified Stock Option financial
"Non-Qualified Stock Option (right to buy)"
A non-qualified stock option (NSO) is a contract that lets an employee or service provider buy company shares at a fixed price for a set period, like a voucher to purchase stock later at today’s price. It matters to investors because exercising NSOs creates ordinary income for the holder and can increase share count, affecting a company’s earnings and ownership mix; think of it as a future sale that can dilute existing shareholders and has immediate tax consequences for the recipient.
Rule 10b5-1(c) regulatory
"plan intended to comply with Rule 10b5-1(c) adopted on February 13, 2026"
Rule 10b5-1(c) is an SEC guideline that lets company insiders set up a written, pre-planned schedule to buy or sell their company stock when they are not in possession of material, nonpublic information. For investors, it matters because such plans can reduce the appearance of insider trading by separating decisions from inside knowledge—like putting your trades on autopilot—while also requiring scrutiny since pre-planned trades can still affect market confidence and share value.
derivative security financial
"Exercise or conversion of derivative security"
A derivative security is a financial contract whose value comes from the price or performance of something else, such as a stock, bond, commodity, or market index. For investors it acts like an insurance policy or a wager: it can be used to protect against losses, lock in prices, or amplify gains and losses, so it can change a portfolio’s risk and potential return without owning the underlying asset directly.

FAQ

What did REGN director Kathryn Guarini report in this Form 4?

Kathryn Guarini exercised 400 stock options for Regeneron Common Stock at $719.37 per share and sold 400 shares at $800.00 per share on August 10, 2026, under a Rule 10b5-1 trading plan.

How many Regeneron (REGN) options did Kathryn Guarini exercise and at what price?

She exercised 400 non-qualified stock options for Regeneron Common Stock at an exercise price of $719.37 per share. These options are part of a grant with remaining options that continue to be exercisable until January 2, 2035.

At what price did Kathryn Guarini sell Regeneron (REGN) shares on August 10, 2026?

She sold 400 shares of Regeneron Common Stock at $800.00 per share on August 10, 2026. The sale followed the same-day option exercise and was carried out under a Rule 10b5-1(c) trading plan.

How many Regeneron (REGN) options does Kathryn Guarini still hold after these transactions?

Following the reported exercise, she holds 1,558 non-qualified stock options to acquire Regeneron Common Stock. These options are scheduled to expire on January 2, 2035, if not exercised earlier.

Were Kathryn Guarini’s Regeneron (REGN) trades under a Rule 10b5-1 plan?

Yes. The Form 4 notes that the disposition and acquisition were made under a plan intended to comply with Rule 10b5-1(c), which was adopted on February 13, 2026, before the August 10, 2026 transactions.

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SEC Form 4
FORM 4UNITED 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*
Guarini Kathryn

(Last)(First)(Middle)
777 OLD SAW MILL RIVER ROAD

(Street)
TARRYTOWN NEW YORK 10591

(City)(State)(Zip)

UNITED STATES

(Country)
2. Issuer Name and Ticker or Trading Symbol
REGENERON PHARMACEUTICALS, INC. [ REGN ]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
XDirector10% Owner
Officer (give title below)Other (specify below)
2a. Foreign Trading Symbol
3. Date of Earliest Transaction (Month/Day/Year)
08/10/2026
6. Individual or Joint/Group Filing (Check Applicable Line)
XForm 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)
CodeVAmount(A) or (D)Price
Common Stock08/10/2026M(1)400A$719.371,003D
Common Stock08/10/2026S(1)400D$800603D
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)
CodeV(A)(D)Date ExercisableExpiration DateTitleAmount or Number of Shares
Non-Qualified Stock Option (right to buy)$719.3708/10/2026M(1)400 (2)01/02/2035Common Stock400$0.01,558D
Explanation of Responses:
1. Disposition/acquisition made pursuant to a plan intended to comply with Rule 10b5-1(c) adopted on February 13, 2026.
2. 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/ Kathryn Guarini08/12/2026
** Signature of Reporting PersonDate
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)