Xenon Pharmaceuticals (XENE) CEO exercises 290,000 options and sells shares under 10b5-1 plans

Rhea-AI Filing Summary

Xenon Pharmaceuticals Inc. President & CEO Ian Mortimer reported a combination of option exercises, performance share vesting and share sales. He exercised stock options covering 290,000 Common Shares at exercise prices between $3.10 and $9.44 per share, and a 20,000-unit performance share award vested based on milestone achievement.

Across multiple open-market transactions, he sold a total of 281,269 Common Shares at weighted-average prices generally between the high-$50s and low-$60s. Footnotes state these sales were made under Rule 10b5‑1 trading arrangements, including a durable sell-to-cover instruction adopted solely to satisfy tax withholding on the vested performance share units. After these transactions, he holds 14,731 Common Shares directly and 14,300 Common Shares indirectly through his spouse.

Insights

Equity compensation and insider-trading analyst

CEO executes large option exercises and mostly pre-planned sales, with limited net share change.

The reporting shows 290,000 Common Shares acquired via option exercises at strike prices from $3.10 to $9.44, plus 20,000 performance share units earned and vested after milestone-based approval by the Board on a March 11, 2024 grant.

On the disposition side, Mortimer sold 281,269 Common Shares, with Form 4 footnotes explaining that these were executed through Rule 10b5‑1 trading arrangements. One arrangement is described as a durable sell-to-cover instruction adopted on December 3, 2025, used solely to meet tax withholding from PSU vesting, which reduces the signaling value of those particular sales.

Following the transactions, he holds 14,731 Common Shares directly and 14,300 indirectly via his spouse, indicating that while the gross sale volume is large, the filing reflects a mix of compensation realization, tax-related activity, and some remaining equity exposure. Overall, this appears as a routine monetization and tax-management event rather than a clear shift in outlook, so the impact assessment is neutral.

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
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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^*

MORTIMER IAN

(Last) (First) (Middle)

3650 GILMORE WAY

(Street)

BURNABY A1 V5G 4W8

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
Xenon Pharmaceuticals Inc. [ XENE ]

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

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

3. Date of Earliest Transaction (Month/Day/Year)
03/09/2026

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 Shares	03/09/2026		M		75,000	A	$8.4	81,000	D
Common Shares	03/09/2026		S(1)		21,791	D	$58.81(2)	59,209	D
Common Shares	03/09/2026		S(1)		31,694	D	$59.88(3)	27,515	D
Common Shares	03/09/2026		S(1)		21,515	D	$60.49(4)	6,000	D
Common Shares	03/09/2026		M		25,000	A	$3.1	31,000	D
Common Shares	03/09/2026		S(1)		12,479	D	$59.5(5)	18,521	D
Common Shares	03/09/2026		S(1)		10,072	D	$60.47(6)	8,449	D
Common Shares	03/09/2026		S(1)		2,449	D	$61.26(7)	6,000	D
Common Shares	03/09/2026		M		105,000	A	$4.75	111,000	D
Common Shares	03/09/2026		S(1)		43,348	D	$59.26(8)	72,652	D
Common Shares	03/09/2026		S(1)		61,652	D	$60.08(9)	6,000	D
Common Shares	03/09/2026		M		65,000	A	$9.44	71,000	D
Common Shares	03/09/2026		S(1)		65,000	D	$62.06(10)	6,000	D
Common Shares	03/09/2026		M		20,000(11)	A	(11)	26,000	D
Common Shares	03/10/2026		S(12)		11,269	D	$60.108	14,731	D
Common Shares								14,300	I	By Spouse

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	$8.4	03/09/2026		M			75,000	(13)	03/12/2027	Common Shares	75,000	$0	0	D
Stock Option	$3.1	03/09/2026		M			25,000	(13)	10/22/2027	Common Shares	25,000	$0	0	D
Stock Option	$4.75	03/09/2026		M			105,000	(13)	03/11/2028	Common Shares	105,000	$0	0	D
Stock Option	$9.44	03/09/2026		M			65,000	(13)	09/15/2029	Common Shares	65,000	$0	0	D
Performance Share Units	(11)	03/09/2026		A		20,000(11)		(11)	(11)	Common Shares	20,000	$0	20,000	D
Performance Share Units	(11)	03/09/2026		M			20,000	(11)	(11)	Common Shares	20,000	$0	0	D

Explanation of Responses:

1. The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on September 27, 2024.

2. The "Amount" and "Price" reported in this Column 4 reflect the aggregate number and weighted-average price (rounded to two decimal places), respectively, or shares sold. These shares were sold in multiple transactions at prices ranging from $58.16 to $59.1425, inclusive. The reporting person undertakes to provide to the issuer, any security holder of the issuer, or the SEC staff, upon request, full information regarding the number of shares sold at each separate price within the range set forth herein.

3. The "Amount" and "Price" reported in this Column 4 reflect the aggregate number and weighted-average price (rounded to two decimal places), respectively, or shares sold. These shares were sold in multiple transactions at prices ranging from $59.16 to $60.15, inclusive. The reporting person undertakes to provide to the issuer, any security holder of the issuer, or the SEC staff, upon request, full information regarding the number of shares sold at each separate price within the range set forth herein.

4. The "Amount" and "Price" reported in this Column 4 reflect the aggregate number and weighted-average price (rounded to two decimal places), respectively, or shares sold. These shares were sold in multiple transactions at prices ranging from $60.16 to $61.00, inclusive. The reporting person undertakes to provide to the issuer, any security holder of the issuer, or the SEC staff, upon request, full information regarding the number of shares sold at each separate price within the range set forth herein.

5. The "Amount" and "Price" reported in this Column 4 reflect the aggregate number and weighted-average price (rounded to two decimal places), respectively, or shares sold. These shares were sold in multiple transactions at prices ranging from $59.03 to $60.02, inclusive. The reporting person undertakes to provide to the issuer, any security holder of the issuer, or the SEC staff, upon request, full information regarding the number of shares sold at each separate price within the range set forth herein.

6. The "Amount" and "Price" reported in this Column 4 reflect the aggregate number and weighted-average price (rounded to two decimal places), respectively, or shares sold. These shares were sold in multiple transactions at prices ranging from $60.05 to $61.035, inclusive. The reporting person undertakes to provide to the issuer, any security holder of the issuer, or the SEC staff, upon request, full information regarding the number of shares sold at each separate price within the range set forth herein.

7. The "Amount" and "Price" reported in this Column 4 reflect the aggregate number and weighted-average price (rounded to two decimal places), respectively, or shares sold. These shares were sold in multiple transactions at prices ranging from $61.055 to $61.555, inclusive. The reporting person undertakes to provide to the issuer, any security holder of the issuer, or the SEC staff, upon request, full information regarding the number of shares sold at each separate price within the range set forth herein.

8. The "Amount" and "Price" reported in this Column 4 reflect the aggregate number and weighted-average price (rounded to two decimal places), respectively, or shares sold. These shares were sold in multiple transactions at prices ranging from $58.745 to $59.735, inclusive. The reporting person undertakes to provide to the issuer, any security holder of the issuer, or the SEC staff, upon request, full information regarding the number of shares sold at each separate price within the range set forth herein.

9. The "Amount" and "Price" reported in this Column 4 reflect the aggregate number and weighted-average price (rounded to two decimal places), respectively, or shares sold. These shares were sold in multiple transactions at prices ranging from $59.75 to $60.60, inclusive. The reporting person undertakes to provide to the issuer, any security holder of the issuer, or the SEC staff, upon request, full information regarding the number of shares sold at each separate price within the range set forth herein.

10. The "Amount" and "Price" reported in this Column 4 reflect the aggregate number and weighted-average price (rounded to two decimal places), respectively, or shares sold. These shares were sold in multiple transactions at prices ranging from $62.00 to $62.30, inclusive. The reporting person undertakes to provide to the issuer, any security holder of the issuer, or the SEC staff, upon request, full information regarding the number of shares sold at each separate price within the range set forth herein.

11. Represents shares earned and vested under a performance share unit ("PSU") award granted to the reporting person on March 11, 2024. The number of shares earned is based on a determination by the issuer's Board of Directors of the achievement of one or more prescribed milestones under the terms of the PSU award agreement. The PSUs vested immediately upon such determination.

12. The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading arrangement, in the form of a durable sell-to-cover instruction, adopted by the reporting person on December 3, 2025, solely to satisfy tax withholding obligations related to the vesting of PSUs granted on March 11, 2024.

13. The shares subject to this option are fully vested and exercisable.

	/s/ Nathaniel Adams, Attorney-in-fact	03/11/2026
	** 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).
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FAQ

What did Xenon Pharmaceuticals (XENE) CEO Ian Mortimer do in this Form 4?

Ian Mortimer exercised options on 290,000 Xenon Common Shares, received 20,000 performance share units upon milestone vesting, and sold 281,269 shares in multiple transactions, largely under Rule 10b5‑1 trading arrangements and a tax-focused sell-to-cover instruction.

How many Xenon Pharmaceuticals (XENE) shares did the CEO sell, and at what prices?

Mortimer sold 281,269 Common Shares in a series of trades. Footnotes state these were executed at weighted-average prices across ranges generally from about $58.16 to $62.30 per share, with detailed per-price breakdowns available upon request from the company or SEC staff.

Were Xenon (XENE) CEO share sales under a Rule 10b5-1 trading plan?

Yes. Footnotes explain the sales were made under Rule 10b5‑1 trading arrangements. One plan, adopted on September 27, 2024, and another durable sell-to-cover instruction adopted on December 3, 2025, governed these transactions and helped automate sales timing and amounts.

What performance share units did the Xenon (XENE) CEO receive and vest?

Mortimer earned and vested 20,000 performance share units from an award granted on March 11, 2024. The Board determined that one or more prescribed milestones were achieved under the PSU agreement, causing the units to vest immediately and convert into Common Shares for the CEO.

How many Xenon Pharmaceuticals (XENE) shares does the CEO own after these transactions?

After all reported exercises and sales, Mortimer holds 14,731 Common Shares directly. He also has an indirect holding of 14,300 Common Shares classified as owned "By Spouse," reflecting additional exposure through a related party position noted in the filing.

Were any Xenon (XENE) CEO share sales purely for tax withholding purposes?

The filing states some sales were under a Rule 10b5‑1 durable sell-to-cover instruction adopted on December 3, 2025. These trades were made solely to satisfy tax withholding obligations from the vesting of performance share units granted on March 11, 2024.