DiFabio Andrea 4

4 · Xenon Pharmaceuticals Inc. · Filed Mar 11, 2026

AI-generated summary of this filing

Updated Mar 11, 2026

Xenon (XENE) CLO Andrea DiFabio Sells 2,607 Shares

What Happened

Andrea DiFabio, Chief Legal Officer of Xenon Pharmaceuticals (XENE), had 7,500 performance share units (PSUs) vest and convert to common shares (reported as an award/derivative conversion on 2026-03-09). Following the conversion, she sold 2,607 shares in the open market on 2026-03-10 at $60.11 per share for total proceeds of $156,702. The conversion shows $0 exercise price, consistent with PSUs converting rather than an option purchase.

Key Details

Transaction dates and prices:
- 2026-03-09: PSUs vested/converted to 7,500 shares (grant A / conversion M; $0.00 exercise).
- 2026-03-10: Open-market sale of 2,607 shares at $60.11 each, proceeds $156,702 (sale S).
Shares owned after transaction: Not specified in this Form 4 filing.
Footnotes:
- F1: The 7,500 shares were earned under PSUs granted March 11, 2024; vesting was based on milestone achievement and occurred upon Board determination.
- F2: The sale was executed under a Rule 10b5-1 durable sell-to-cover instruction adopted Dec 3, 2025, solely to satisfy tax withholding from the PSU vesting.
Filing timeliness: Form filed March 11, 2026 for transactions on March 9–10; appears to be filed within the usual Form 4 timeframe.

Context

This sequence is a routine vesting-and-sell-to-cover: PSUs vested and converted to shares (no cash paid on conversion), and a portion was sold automatically under a pre-established 10b5-1 plan to cover tax obligations. Such sell-to-cover transactions are common after equity awards and do not necessarily signal an insider view on the company’s prospects.

Form 4

Period: 2026-03-09

Chief Legal Officer

Transactions

Exercise/Conversion
Common Shares
[F1]
2026-03-09+7,500→ 7,500 total
Sale
Common Shares
[F2]
2026-03-10$60.11/sh−2,607$156,702→ 4,893 total
Award
Performance Share Units
[F1]
2026-03-09+7,500→ 7,500 total
→ Common Shares (7,500 underlying)
Exercise/Conversion
Performance Share Units
[F1]
2026-03-09−7,500→ 0 total
→ Common Shares (7,500 underlying)

Footnotes (2)

[F1]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.
[F2]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.

Signature

/s/ Nathaniel Adams, Attorney-in-fact|2026-03-11

1 file