[Form 4] ALNYLAM PHARMACEUTICALS, INC. Insider Trading Activity

Rhea-AI Filing Summary

Alnylam Pharmaceuticals (ALNY) EVP Chief R&D Pushkal Garg reported PSU vesting and related share sales. On 10/01/2025, he acquired 3,108 and 2,851 common shares at $0.00 upon vesting tied to the company publicly reporting the initiation of Phase 3 clinical studies, as determined by the Board’s PC&C Committee.

On 10/02/2025, shares were sold automatically to cover taxes from the PSU settlements at disclosed weighted average prices by tranche; additional sales on 10/03/2025 were made under a Rule 10b5‑1(c) trading plan adopted on 09/11/2024. After these transactions, direct holdings were 20,221 shares, with 431 held via a managed account and 250 held in a trust.

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^*

Garg Pushkal

(Last) (First) (Middle)

675 WEST KENDALL STREET

HENRI A. TERMEER SQUARE

(Street)

CAMBRIDGE MA 02142

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
ALNYLAM PHARMACEUTICALS, INC. [ ALNY ]

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

	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	EVP Chief R&D

3. Date of Earliest Transaction (Month/Day/Year)
10/01/2025

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	10/01/2025		A(1)		3,108	A	$0.0	23,329	D
Common Stock	10/01/2025		A(2)		2,851	A	$0.0	26,180	D
Common Stock	10/02/2025		S(3)		115	D	$446.53(4)	26,065	D
Common Stock	10/02/2025		S(3)		56	D	$447.92(5)	26,009	D
Common Stock	10/02/2025		S(3)		180	D	$448.77(6)	25,829	D
Common Stock	10/02/2025		S(3)		249	D	$449.79(7)	25,580	D
Common Stock	10/02/2025		S(3)		541	D	$450.81(8)	25,039	D
Common Stock	10/02/2025		S(3)		332	D	$451.86(9)	24,707	D
Common Stock	10/02/2025		S(3)		668	D	$452.69(10)	24,039	D
Common Stock	10/02/2025		S(3)		329	D	$453.77(11)	23,710	D
Common Stock	10/02/2025		S(3)		244	D	$454.84(12)	23,466	D
Common Stock	10/02/2025		S(3)		73	D	$455.82(13)	23,393	D
Common Stock	10/02/2025		S(3)		147	D	$457.43	23,246	D
Common Stock	10/02/2025		S(3)		3	D	$457.64	23,243	D
Common Stock	10/03/2025		S(14)		682	D	$449.99(15)	22,561	D
Common Stock	10/03/2025		S(14)		810	D	$450.63(16)	21,751	D
Common Stock	10/03/2025		S(14)		898	D	$451.76(17)	20,853	D
Common Stock	10/03/2025		S(14)		417	D	$453.51(18)	20,436	D
Common Stock	10/03/2025		S(14)		215	D	$454.37(19)	20,221	D
Common Stock								431	I	by Managed Account(20)
Common Stock								250	I	by Trust(21)

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

Explanation of Responses:

1. On February 24, 2021, the reporting person was granted a performance-based stock unit (PSU) under the 2018 Stock Incentive Plan. The shares subject to the PSU vest based on the achievement of four specified performance measures. The shares reported were issued to the reporting person upon vesting of one-quarter of the shares subject to the PSU based on the issuer publicly reporting the initiation of a Phase 3 clinical study of an RNAi therapeutic in development to treat a prevalent disease, as determined by the People, Culture and Compensation (PC&C) Committee of the Issuer Board of Directors on October 1, 2025.

2. On March 1, 2024, the reporting person was granted a PSU under the 2018 Stock Incentive Plan. The shares subject to the PSU vest based on the achievement of three specified performance measures. The shares reported were issued to the reporting person upon vesting of thirty (30) percent of the shares subject to the PSU based on the issuer publicly reporting the initiation of a Phase 3 clinical study in a prevalent indication, as determined by the PC&C Committee on October 1, 2025.

3. 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 required to cover minimum statutory tax withholding obligations that became due upon the vesting and settlement of tranches of PSUs granted to the reporting person on February 24, 2021 and March 1, 2024.

4. The price reported represents the weighted average sales price of shares sold in multiple transactions at prices ranging from $446.19 to $447.19. 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.

5. The price reported represents the weighted average sales price of shares sold in multiple transactions at prices ranging from $447.21 to $448.21. 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.

6. The price reported represents the weighted average sales price of shares sold in multiple transactions at prices ranging from $448.25 to $449.24. 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.

7. The price reported represents the weighted average sales price of shares sold in multiple transactions at prices ranging from $449.26 to $450.26. 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.

8. The price reported represents the weighted average sales price of shares sold in multiple transactions at prices ranging from $450.29 to $451.29. 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.

9. The price reported represents the weighted average sales price of shares sold in multiple transactions at prices ranging from $451.31 to $452.31. 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.

10. The price reported represents the weighted average sales price of shares sold in multiple transactions at prices ranging from $452.33 to $453.31. 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.

11. The price reported represents the weighted average sales price of shares sold in multiple transactions at prices ranging from $453.37 to $454.37. 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.

12. The price reported represents the weighted average sales price of shares sold in multiple transactions at prices ranging from $454.38 to $455.34. 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.

13. The price reported represents the weighted average sales price of shares sold in multiple transactions at prices ranging from $455.42 to $456.09. 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.

14. This transaction was made pursuant to a Rule 10b5-1(c) trading plan adopted by the Reporting Person on September 11, 2024.

15. The price reported represents the weighted average sales price of shares sold in multiple transactions at prices ranging from $449.37 to $450.31. 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.

16. The price reported represents the weighted average sales price of shares sold in multiple transactions at prices ranging from $450.47 to $451.16. 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.

17. The price reported represents the weighted average sales price of shares sold in multiple transactions at prices ranging from $451.50 to $452.43. 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.

18. The price reported represents the weighted average sales price of shares sold in multiple transactions at prices ranging from $452.94 to $453.75. 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.

19. The price reported represents the weighted average sales price of shares sold in multiple transactions at prices ranging from $454.25 to $454.76. 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.

20. 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.

21. Represents shares held in trust, of which the Reporting Persons spouse is co-trustee. The Reporting Person disclaims beneficial ownership of these shares, and the filing of this report is not an admission that the Reporting Person is the beneficial owner of these securities for purposes of Section 16 or for any other purpose.

	By: Brett Budzinski, Attorney-in-Fact For: Pushkal Garg	10/03/2025
	** 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 did ALNY’s EVP report on Form 4?

Pushkal Garg reported PSU vesting and subsequent share sales, including sell-to-cover transactions and trades under a Rule 10b5-1(c) plan.

How many ALNY shares vested on 10/01/2025?

Two PSU tranches vested, resulting in acquisitions of 3,108 shares and 2,851 shares at $0.00 each.

Why were ALNY shares sold on 10/02/2025?

They were automatically sold to cover minimum statutory tax withholding from the PSU vesting settlements.

Were any sales under a Rule 10b5-1 plan?

Yes. Sales on 10/03/2025 were made under a Rule 10b5-1(c) plan adopted on 09/11/2024.

What are the reported direct and indirect ALNY holdings after the transactions?

Direct holdings: 20,221 shares. Indirect: 431 via a managed account and 250 in a trust.

What prices were disclosed for the sales?

Weighted average prices were provided by tranche, including values such as $449.99, $450.63, and $451.76, among others.

What triggered the PSU vesting?

Vesting was based on the issuer publicly reporting initiation of Phase 3 clinical studies in prevalent indications, as determined on 10/01/2025 by the PC&C Committee.