Vanguard Portfolio Management holds 4.10M WST shares (5.69%) — WST

Rhea-AI Filing Summary

West Pharmaceutical Services Inc ownership disclosure: Vanguard Portfolio Management reports beneficial ownership of 4,102,674 shares of Common Stock, representing 5.69% of the class as of 03/31/2026. Vanguard Portfolio Management indicates sole dispositive power over 4,102,674 shares and sole voting power over 8,665 shares. The filing describes holdings managed across Vanguard affiliates and notes the ownership reflects securities held by Vanguard funds and client accounts.

Insights

Institutional Ownership Analyst

Vanguard reports a 5.69% stake with dispositive control across managed vehicles.

Vanguard Portfolio Management discloses beneficial ownership of 4,102,674 shares and sole dispositive power over the same amount as of 03/31/2026. The filing attributes voting and dispositive authority to Vanguard Portfolio Management LLC and affiliated business units.

Key dependencies include which Vanguard funds or client accounts hold the shares; the filing notes that other Vanguard affiliates' holdings may be disaggregated. Subsequent filings or amendments would show any material changes in stake or voting arrangements.

Key Figures

Shares beneficially owned: 4,102,674 shares Percent of class: 5.69% Sole voting power: 8,665 shares +2 more

5 metrics

Shares beneficially owned 4,102,674 shares as of 03/31/2026

Percent of class 5.69% percentage of outstanding common stock

Sole voting power 8,665 shares voting power reported in Item 4

Sole dispositive power 4,102,674 shares dispositive power reported in Item 4

CUSIP 955306105 West Pharmaceutical Common Stock CUSIP

Key Terms

Schedule 13G, beneficially owned, dispositive power, Investment Company Act

4 terms

Schedule 13G regulatory

"Beneficial ownership disclosure filed as Schedule 13G"

A Schedule 13G is a formal document that investors file with the government when they acquire a large ownership stake in a company, usually for investment purposes rather than control. It helps keep the public informed about who owns significant parts of a company's shares, which can influence how the company is managed and how investors make decisions. Filing this schedule is important for transparency and understanding the ownership landscape of publicly traded companies.

beneficially owned financial

"This reflects the securities beneficially owned, or deemed to be beneficially owned"

Beneficially owned describes securities or assets where a person has the economic rights and control—such as the right to receive dividends and to direct voting—even if legal title is held in another name. Think of it like having the keys and using a car that’s registered to someone else: you get the benefits and make decisions. Investors care because beneficial ownership reveals who truly controls value and voting power, affecting corporate decisions and takeover dynamics.

dispositive power legal

"Sole power to dispose or to direct the disposition of: 4102674"

Dispositive power is the authority to decide the final outcome of an asset, legal claim, contract, or corporate action — in effect the power to dispose of or resolve something. For investors it matters because whoever holds that authority can determine who gets paid, who controls an asset or vote, and how risks and returns are allocated; think of it like holding the key that lets you lock in the winner or loser in a deal.

Investment Company Act regulatory

"investment company registered under the Investment Company Act of 1940"

The Investment Company Act is a law that sets rules for businesses whose main activity is managing and selling pooled money, such as mutual funds and other investment funds. It matters to investors because it requires clear reporting, limits managers from putting their own interests ahead of clients, and mandates safekeeping and oversight of assets—similar to safety inspections and traffic rules that help keep shared vehicles reliable and trustworthy.

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 13G

UNDER THE SECURITIES EXCHANGE ACT OF 1934

West Pharmaceutical Services Inc

(Name of Issuer)

Common Stock

(Title of Class of Securities)

955306105

(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): 955306105

1

Names of Reporting Persons

Vanguard Portfolio Management

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

PENNSYLVANIA

Number of Shares Beneficially Owned by Each Reporting Person With:

5	Sole Voting Power 8,665.00
6	Shared Voting Power 0.00
7	Sole Dispositive Power 4,102,674.00
8	Shared Dispositive Power 0.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

4,102,674.00

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)

5.69 %

12

Type of Reporting Person (See Instructions)

IA

Comment for Type of Reporting Person: In accordance with SEC Release No. 34-39538 (January 12, 1998), this Schedule 13G reflects the securities beneficially owned, or deemed to be beneficially owned, by Vanguard Portfolio Management LLC and the following affiliates of Vanguard Portfolio Management LLC or business divisions of such affiliates: Vanguard Fiduciary Trust Company and Vanguard Global Advisers, LLC. This Schedule 13G includes securities held by Vanguard funds, or sleeves thereof, over which Vanguard Portfolio Management LLC exercises dispositive power, in addition to securities held by clients over which the affiliates or business divisions of such affiliates indicated above exercise dispositive and/or voting power. This Schedule 13G does not include securities, if any, beneficially owned by other subsidiaries or affiliates of Vanguard Portfolio Management LLC, or business divisions of such subsidiaries whose ownership of securities is disaggregated from that of the reporting business unit in accordance with such release.

SCHEDULE 13G

Item 1.
(a)	Name of issuer: West Pharmaceutical Services Inc
(b)	Address of issuer's principal executive offices: 530 Herman O West Dr, Exton, PA, 19341
Item 2.
(a)	Name of person filing: Vanguard Portfolio Management
(b)	Address or principal business office or, if none, residence: 100 Vanguard Blvd,, Malvern, PA, 19355
(c)	Citizenship: PA
(d)	Title of class of securities: Common Stock
(e)	CUSIP Number(s): 955306105
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: 4102674
(b)	Percent of class: 5.69 %
(c)	Number of shares as to which the person has:
	(i) Sole power to vote or to direct the vote: 8665
	(ii) Shared power to vote or to direct the vote: 0
	(iii) Sole power to dispose or to direct the disposition of: 4102674
	(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.
	If any other person is known to have the right to receive or the power to direct the receipt of dividends from, or the proceeds from the sale of, such securities, a statement to that effect should be included in response to this item and, if such interest relates to more than 5 percent of the class, such person should be identified. A listing of the shareholders of an investment company registered under the Investment Company Act of 1940 or the beneficiaries of employee benefit plan, pension fund or endowment fund is not required. Vanguard Portfolio Management, including investment companies registered under the Investment Company Act of 1940 and other managed accounts, have the right to receive or the power to direct the receipt of dividends from, or the proceeds from the sale of, the securities reported herein.No one other person's interest in the securities reported herein is more than 5%.
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.

Vanguard Portfolio Management

Signature:	Ashley Grim
Name/Title:	Head of Global Fund Administration
Date:	04/29/2026

FAQ

What stake does Vanguard Portfolio Management hold in WST?

Vanguard Portfolio Management reports beneficial ownership of 4,102,674 shares of WST, representing 5.69% of the class as of 03/31/2026. The filing attributes dispositive power to Vanguard Portfolio Management LLC and related affiliates.

How much voting power does Vanguard have over WST shares?

The filing states Vanguard has sole voting power over 8,665 shares of WST. It reports sole dispositive power over 4,102,674 shares, indicating voting and disposition authorities are recorded separately.

Does the 13G filing identify which Vanguard entities hold the shares?

The filing names Vanguard Portfolio Management LLC and affiliates including Vanguard Fiduciary Trust Company and Vanguard Global Advisers, LLC. It states holdings include Vanguard funds and client accounts managed by those business units.

What date does the ownership snapshot cover in the WST filing?

The ownership figures are reported as of 03/31/2026. The Schedule 13G was signed on 04/29/2026, which is the filing signature date and not the as‑of ownership date.

Is any single other person reported to own more than 5% of WST?

The filing states no other single person's interest in these reported securities exceeds 5%. Vanguard indicates it holds shares on behalf of various investment companies and managed accounts.