Alnylam Pharmaceuticals reports a Schedule 13G/A filing showing Capital Research Global Investors holds 9,471,181 shares of common stock. The filing states this represents 7.1% of 132,623,144 shares outstanding. The filing lists 9,455,765 shares with sole voting power and 9,471,181 with sole dispositive power.
Positive
None.
Negative
None.
Insights
Large passive stake disclosed by Capital Research Global Investors.
Capital Research Global Investors is reported as the beneficial owner of 9,471,181 shares, equal to 7.1% of the outstanding common stock. The filing attributes holdings to CRGI and affiliated investment management entities acting under a shared advisory name.
Disclosure is consistent with a Section 13 passive investor filing; timing and trading intent are not stated in the excerpt.
Voting and dispositive power are largely held solely by CRGI per the filing.
The filing shows 9,455,765 shares with sole voting power and 9,471,181 with sole dispositive power. The filing names multiple affiliated entities that provide investment management services under the Capital Research Global Investors banner.
Further changes in holdings would be reported in subsequent amendments as required by rule; no acquisition/disposition details appear here.
Key Figures
Beneficial ownership:9,471,181 sharesPercent of class:7.1%Shares outstanding:132,623,144 shares+2 more
Percent of class7.1%of 132,623,144 shares outstanding
Shares outstanding132,623,144 sharesshares believed to be outstanding
Sole voting power9,455,765 sharessole power to vote
Sole dispositive power9,471,181 sharessole power to dispose
Key Terms
Schedule 13G/A, Beneficial owner, Sole dispositive power, Sole voting power
4 terms
Schedule 13G/Aregulatory
"Capital Research Global Investors files a Schedule 13G/A"
A Schedule 13G/A is an amended public filing with the U.S. securities regulator that updates a previous Schedule 13G, disclosing when an individual or group holds a substantial (typically over 5%) stake in a company and is claiming a passive, non‑controlling intent. Investors monitor these updates because rising or falling holdings can signal changing confidence, potential future moves, or shifts in voting power — like watching a public ledger where large shareholders quietly adjust their positions.
Beneficial ownerregulatory
"CRGI is deemed to be the beneficial owner of 9,471,181 shares"
A beneficial owner is the person who ultimately owns or controls a financial asset or property, even if their name isn't directly on official documents. Think of it like someone who secretly holds the keys to a safe deposit box—others may appear to have access, but the true owner is the one who benefits from what's inside. Identifying beneficial owners helps ensure transparency and prevent illegal activities like money laundering or fraud.
Sole dispositive powerregulatory
"Sole power to dispose or to direct the disposition of: 9,471,181"
Sole dispositive power is the exclusive legal authority to decide what happens to a security — for example, whether to sell, transfer, or retain shares — without needing anyone else’s permission. Investors care because it signals who truly controls the economic outcome of an investment: like holding the only key to a safe, the holder can realize gains or losses and may trigger regulatory reporting, insider rules, or influence over corporate ownership.
Sole voting powerregulatory
"Sole power to vote or to direct the vote: 9,455,765"
Sole voting power is the exclusive right to cast votes attached to a shareholder’s stock without needing approval from anyone else. Like holding the only remote control for a TV, it lets that holder decide corporate matters such as board members, mergers, and policy changes, making it important to investors because it concentrates control and can strongly influence a company’s strategy and the value of its shares.
What stake does Capital Research Global Investors report in ALNY?
Capital Research Global Investors reports beneficial ownership of 9,471,181 shares of ALNY common stock, representing 7.1% of 132,623,144 shares outstanding as stated in the filing.
How much voting power does Capital Research Global Investors have in ALNY?
The filing states Capital Research Global Investors has sole voting power over 9,455,765 shares and shared voting power of 0 shares, per the disclosed Schedule 13G/A.
Does the Schedule 13G/A indicate Capital Research will sell or buy more ALNY shares?
The filing discloses beneficial ownership and voting/dispositive powers only; it does not state any intent to buy or sell additional ALNY shares or describe specific trading plans.
Who is included in the ownership disclosure for ALNY?
The filing attributes ownership to Capital Research Global Investors and affiliated investment management entities, including Capital Research and Management Company and specified subsidiaries that provide services under the CRGI name.
When was the Schedule 13G/A signature dated for ALNY?
The Schedule 13G/A excerpt is signed by Jae Won Chung, Vice President and Senior Counsel II, Capital Research and Management Company, with a signature date of 05/11/2026 shown in the filing.
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
SCHEDULE 13G
UNDER THE SECURITIES EXCHANGE ACT OF 1934
(Amendment No. 1)
Alnylam Pharmaceuticals, Inc.
(Name of Issuer)
Common Stock
(Title of Class of Securities)
02043Q107
(CUSIP Number)
03/31/2026
(Date of Event Which Requires Filing of this Statement)
Check the appropriate box to designate the rule pursuant to which this Schedule is filed:
Rule 13d-1(b)
Rule 13d-1(c)
Rule 13d-1(d)
schemaVersion:
SCHEDULE 13G
CUSIP Number(s):
02043Q107
1
Names of Reporting Persons
Capital Research Global Investors
2
Check the appropriate box if a member of a Group (see instructions)
(a)
(b)
3
Sec Use Only
4
Citizenship or Place of Organization
DELAWARE
Number of Shares Beneficially Owned by Each Reporting Person With:
5
Sole Voting Power
9,455,765.00
6
Shared Voting Power
0.00
7
Sole Dispositive Power
9,471,181.00
8
Shared Dispositive Power
0.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
9,471,181.00
10
Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)
11
Percent of class represented by amount in row (9)
7.1 %
12
Type of Reporting Person (See Instructions)
IA
SCHEDULE 13G
Item 1.
(a)
Name of issuer:
Alnylam Pharmaceuticals, Inc.
(b)
Address of issuer's principal executive offices:
675 West Kendall Street, Henri A. Termeer Square, Cambridge, MA 2142
Item 2.
(a)
Name of person filing:
Capital Research Global Investors
(b)
Address or principal business office or, if none, residence:
333 South Hope Street, 55th Fl, Los Angeles, CA 90071
(c)
Citizenship:
N/A
(d)
Title of class of securities:
Common Stock
(e)
CUSIP No.:
02043Q107
Item 3.
If this statement is filed pursuant to §§ 240.13d-1(b) or 240.13d-2(b) or (c), check whether the person filing is a:
(a)
Broker or dealer registered under section 15 of the Act (15 U.S.C. 78o);
(b)
Bank as defined in section 3(a)(6) of the Act (15 U.S.C. 78c);
(c)
Insurance company as defined in section 3(a)(19) of the Act (15 U.S.C. 78c);
(d)
Investment company registered under section 8 of the Investment Company Act of 1940 (15 U.S.C. 80a-8);
(e)
An investment adviser in accordance with § 240.13d-1(b)(1)(ii)(E);
(f)
An employee benefit plan or endowment fund in accordance with § 240.13d-1(b)(1)(ii)(F);
(g)
A parent holding company or control person in accordance with § 240.13d-1(b)(1)(ii)(G);
(h)
A savings associations as defined in Section 3(b) of the Federal Deposit Insurance Act (12 U.S.C. 1813);
(i)
A church plan that is excluded from the definition of an investment company under section 3(c)(14) of the Investment Company Act of 1940 (15 U.S.C. 80a-3);
(j)
A non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J). If filing as a non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J),
please specify the type of institution:
(k)
Group, in accordance with Rule 240.13d-1(b)(1)(ii)(K).
Item 4.
Ownership
(a)
Amount beneficially owned:
9,471,181 **
**Capital Research Global Investors ("CRGI") is a division of Capital Research and Management Company ("CRMC"), as well as its investment management subsidiaries and affiliates Capital Bank and Trust Company, Capital International, Inc., Capital International Limited, Capital International Sarl, Capital International K.K., Capital Group Private Client Services, Inc., and Capital Group Investment Management Private Limited (together with CRMC, the "investment management entities"). CRGI's divisions of each of the investment management entities collectively provide investment management services under the name "Capital Research Global Investors." CRGI is deemed to be the beneficial owner of 9,471,181 shares or 7.1% of the 132,623,144 shares believed to be outstanding.
(b)
Percent of class:
7.1 %
(c)
Number of shares as to which the person has:
(i) Sole power to vote or to direct the vote:
9,455,765
(ii) Shared power to vote or to direct the vote:
0
(iii) Sole power to dispose or to direct the disposition of:
9,471,181
(iv) Shared power to dispose or to direct the disposition of:
0
Item 5.
Ownership of 5 Percent or Less of a Class.
Not Applicable
Item 6.
Ownership of more than 5 Percent on Behalf of Another Person.
Not Applicable
Item 7.
Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on by the Parent Holding Company or Control Person.
Not Applicable
Item 8.
Identification and Classification of Members of the Group.
Not Applicable
Item 9.
Notice of Dissolution of Group.
Not Applicable
Item 10.
Certifications:
By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were acquired and are held in the ordinary course of business and were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect, other than activities solely in connection with a nomination under ?? 240.14a-11.
SIGNATURE
After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.
Capital Research Global Investors
Signature:
Jae Won Chung
Name/Title:
Vice President and Senior Counsel II, Capital Research and Management Company
