Fitzgerald Kevin Joseph 4

4 · ALNYLAM PHARMACEUTICALS, INC. · Filed Mar 4, 2026

Insider Transaction Report

Form 4

Period: 2026-03-02

ALNYLAM PHARMACEUTICALS, INC.ALNY

Fitzgerald Kevin Joseph

CSO & EVP, Head of Research

Transactions

Award
Common Stock
[F1]
2026-03-02+3,688→ 25,110 total
Sale
Common Stock
[F2][F3]
2026-03-02$323.62/sh−47$15,210→ 25,063 total
Sale
Common Stock
[F2][F4]
2026-03-02$324.65/sh−90$29,218→ 24,973 total
Sale
Common Stock
[F2][F5]
2026-03-02$325.63/sh−258$84,013→ 24,715 total
Sale
Common Stock
[F2][F6]
2026-03-02$326.81/sh−392$128,110→ 24,323 total
Sale
Common Stock
[F2][F7]
2026-03-02$327.67/sh−329$107,803→ 23,994 total
Sale
Common Stock
[F2][F8]
2026-03-02$328.71/sh−100$32,871→ 23,894 total
Sale
Common Stock
[F2][F9]
2026-03-02$329.71/sh−170$56,051→ 23,724 total
Sale
Common Stock
[F2][F10]
2026-03-02$330.85/sh−81$26,799→ 23,643 total
Sale
Common Stock
[F2][F11]
2026-03-02$331.93/sh−94$31,201→ 23,549 total
Sale
Common Stock
[F2][F12]
2026-03-02$332.64/sh−37$12,308→ 23,512 total
Sale
Common Stock
[F13][F14]
2026-03-03$316.55/sh−289$91,483→ 23,223 total
Sale
Common Stock
[F13][F15]
2026-03-03$318.62/sh−282$89,851→ 22,941 total
Sale
Common Stock
[F13][F16]
2026-03-03$320.51/sh−722$231,408→ 22,219 total
Sale
Common Stock
[F13][F17]
2026-03-03$321.58/sh−359$115,447→ 21,860 total
Award
Stock Option (right to buy)
[F19]
2026-03-02+8,105→ 8,105 total
Exercise: $325.07Exp: 2036-03-02→ Common Stock (8,105 underlying)

Holdings

Common Stock
[F18]
(indirect: by Managed Account)
537

Footnotes (19)

[F1]These shares are represented by restricted stock units (RSUs) granted under the Second Amended and Restated 2018 Stock Incentive Plan. Each RSU represents a contingent right to receive one share of common stock. The RSUs will vest over a three-year period, with one third vesting on each of the first, second and third anniversaries of the grant date, subject to the Reporting Persons continuous service with the Issuer as of each such vesting date.
[F10]The price reported represents the weighted average sales price of shares sold in multiple transactions at prices ranging from $330.30 to $331.30. The reporting person will provide to the issuer, any security holder of the issuer or the SEC staff, upon request, information regarding the number of shares sold at each price within the range.
[F11]The price reported represents the weighted average sales price of shares sold in multiple transactions at prices ranging from $331.32 to $332.31. The reporting person will provide to the issuer, any security holder of the issuer or the SEC staff, upon request, information regarding the number of shares sold at each price within the range.
[F12]The price reported represents the weighted average sales price of shares sold in multiple transactions at prices ranging from $332.34 to $332.24. The reporting person will provide to the issuer, any security holder of the issuer or the SEC staff, upon request, information regarding the number of shares sold at each price within the range.
[F13]This transaction was made pursuant to a Rule 10b5-1(c) trading plan adopted by the Reporting Person on August 14, 2025.
[F14]The price reported represents the weighted average sales price of shares sold in multiple transactions at prices ranging from $316.51 to $317.12. The reporting person will provide to the issuer, any security holder of the issuer or the SEC staff, upon request, information regarding the number of shares sold at each price within the range.
[F15]The price reported represents the weighted average sales price of shares sold in multiple transactions at prices ranging from $318.25 to $318.90. The reporting person will provide to the issuer, any security holder of the issuer or the SEC staff, upon request, information regarding the number of shares sold at each price within the range.
[F16]The price reported represents the weighted average sales price of shares sold in multiple transactions at prices ranging from $320.04 to $320.99. The reporting person will provide to the issuer, any security holder of the issuer or the SEC staff, upon request, information regarding the number of shares sold at each price within the range.
[F17]The price reported represents the weighted average sales price of shares sold in multiple transactions at prices ranging from $321.36 to $321.84. The reporting person will provide to the issuer, any security holder of the issuer or the SEC staff, upon request, information regarding the number of shares sold at each price within the range.
[F18]Reflects shares of ALNY common stock acquired by the Reporting Person under the issuer 401(k) plan as a result of the issuer 401(k) matching contribution program.
[F19]The stock option vests as to 25% of the shares on the first anniversary of the grant date and the remaining shares vest in equal installments at the end of each successive three-month period thereafter until the fourth anniversary of the grant date, subject to the Reporting Persons continuous service with the Issuer as of each such vesting date.
[F2]Represents shares automatically sold by the Company on behalf of the reporting person pursuant to a mandatory sell-to-cover provision in the award agreement to cover minimum statutory tax withholding obligations.
[F3]The price reported represents the weighted average sales price of shares sold in multiple transactions at prices ranging from $323.16 to $324.15. The reporting person will provide to the issuer, any security holder of the issuer or the SEC staff, upon request, information regarding the number of shares sold at each price within the range.
[F4]The price reported represents the weighted average sales price of shares sold in multiple transactions at prices ranging from $324.20 to $325.20. The reporting person will provide to the issuer, any security holder of the issuer or the SEC staff, upon request, information regarding the number of shares sold at each price within the range.
[F5]The price reported represents the weighted average sales price of shares sold in multiple transactions at prices ranging from $325.21 to $326.21. The reporting person will provide to the issuer, any security holder of the issuer or the SEC staff, upon request, information regarding the number of shares sold at each price within the range.
[F6]The price reported represents the weighted average sales price of shares sold in multiple transactions at prices ranging from $326.23 to $327.23. The reporting person will provide to the issuer, any security holder of the issuer or the SEC staff, upon request, information regarding the number of shares sold at each price within the range.
[F7]The price reported represents the weighted average sales price of shares sold in multiple transactions at prices ranging from $327.24 to $328.24. The reporting person will provide to the issuer, any security holder of the issuer or the SEC staff, upon request, information regarding the number of shares sold at each price within the range.
[F8]The price reported represents the weighted average sales price of shares sold in multiple transactions at prices ranging from $328.28 to $329.26. The reporting person will provide to the issuer, any security holder of the issuer or the SEC staff, upon request, information regarding the number of shares sold at each price within the range.
[F9]The price reported represents the weighted average sales price of shares sold in multiple transactions at prices ranging from $329.29 to $330.29. The reporting person will provide to the issuer, any security holder of the issuer or the SEC staff, upon request, information regarding the number of shares sold at each price within the range.

Signature

By: Brett Budzinski, Attorney-in-Fact For: Kevin Fitzgerald|2026-03-04

Documents

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