Company · Ownership research

WEST PHARMACEUTICAL SERVICES INC WST

CIK 0000105770 · CUSIP 955306105

Insider trading Initial holdings Institutional holders

Quarter-end disclosures, not live holdings.

Several CUSIPs are reported for this company; this page shows CUSIP 955306105 (WST), not CUSIP 955306905 (WST), CUSIP 955306955 (WST), and does not merge CUSIPs.

This page lists the top 20 of 431 rows by value; the complete set is available through the API.

Some filings reported values in thousands; those figures were scaled ×1,000 to dollars.

Top 20 institutions

Weight means this stock's share of the manager's own portfolio.

By reported value

#	Manager	Value	Manager weight	Change vs prior	Source
01	GEODE CAPITAL MANAGEMENT, LLC CIK 1214717 · View history	$715.18M 1,936,541 shares	0.04%	+33.26K(+1.70%)Added	SEC filing ↗ Nov 6, 2026	▾
02	Bank of New York Mellon Corp CIK 1390777 · View history	$644.70M 1,738,854 shares	0.11%	-304.97K(-14.90%)Reduced	SEC filing ↗ Nov 5, 2026	▾
03	DIMENSIONAL FUND ADVISORS LP CIK 354204 · View history	$182.03M 490,897 shares	0.03%	-30.81K(-5.90%)Reduced	SEC filing ↗ Nov 4, 2026	▾
04	ProShare Advisors LLC CIK 1357955 · View history	$176.11M 474,984 shares	0.25%	-123.04K(-20.60%)Reduced	SEC filing ↗ Oct 29, 2026	▾
05	DEUTSCHE BANK AG\ CIK 948046 · View history	$148.89M 401,593 shares	0.04%	-9.11K(-2.20%)Reduced	SEC filing ↗ Nov 6, 2026	▾
06	WILLIAM BLAIR INVESTMENT MANAGEMENT, LLC CIK 1644956 · View history	$148.11M 399,467 shares	0.48%	-17.84K(-4.30%)Reduced	SEC filing ↗ Nov 6, 2026	▾
07	DekaBank Deutsche Girozentrale CIK 1456228 · View history	$127.13M 337,647 shares	0.14%	+310.04K(+1,122.90%)Added	SEC filing ↗ Oct 27, 2026	▾
08	Amundi CIK 1330387 · View history	$112.03M 302,163 shares	0.02%	-83.15K(-21.60%)Reduced	SEC filing ↗ Nov 6, 2026	▾
09	CITIGROUP INC CIK 831001 · View history	$82.97M 223,775 shares	0.04%	+33.00K(+17.30%)Added	SEC filing ↗ Nov 4, 2026	▾
10	Border to Coast Pensions Partnership Ltd CIK 1876496 · View history	$81.22M 219,390 shares	1.12%	-7.47K(-3.30%)Reduced	SEC filing ↗ Oct 9, 2026	▾
11	RIVERBRIDGE PARTNERS LLC CIK 1112325 · View history	$77.12M 208,015 shares	2.26%	-24.50K(-10.50%)Reduced	SEC filing ↗ Nov 5, 2026	▾
12	BARCLAYS PLC CIK 312069 · View history	$75.70M 204,168 shares	0.03%	-42.03K(-17.10%)Reduced	SEC filing ↗ Nov 6, 2026	▾
13	Allspring Global Investments Holdings, LLC CIK 1890906 · View history	$74.51M 204,122 shares	0.12%	+200.19K(+5,088.70%)Added	SEC filing ↗ Nov 4, 2026	▾
14	Mitsubishi UFJ Asset Management Co., Ltd. CIK 1466546 · View history	$73.57M 198,442 shares	0.04%	+10.21K(+5.40%)Added	SEC filing ↗ Nov 5, 2026	▾
15	Aberdeen Group plc CIK 1716774 · View history	$71.01M 1,462,033 shares	0.10%	+1.40M(+2,283.10%)Added	SEC filing ↗ Nov 6, 2026	▾
16	Russell Investments Group, Ltd. CIK 1692234 · View history	$66.84M 180,173 shares	0.05%	-91.69K(-33.70%)Reduced	SEC filing ↗ Nov 6, 2026	▾
17	Sumitomo Mitsui Trust Group, Inc. CIK 1475365 · View history	$59.06M 159,302 shares	0.03%	-8.78K(-5.20%)Reduced	SEC filing ↗ Oct 29, 2026	▾
18	Birch Hill Investment Advisors LLC CIK 1424177 · View history	$58.92M 158,911 shares	2.42%	-785(-0.50%)Reduced	SEC filing ↗ Oct 16, 2026	▾
19	Vest Financial, LLC CIK 1709632 · View history	$55.07M 148,537 shares	0.58%	-34.04K(-18.60%)Reduced	SEC filing ↗ Oct 21, 2026	▾
20	AMI ASSET MANAGEMENT CORP CIK 1369702 · View history	$52.48M 141,556 shares	3.01%	-5.21K(-3.50%)Reduced	SEC filing ↗ Oct 20, 2026	▾

Showing 20 / 431 institutions. The complete set is available through the API.

Coverage & totals by quarter

Reporting institutions

431

Cancelled or null records excluded

Disclosed shares

12,672,771

Not deduplicated across managers

Disclosed value

$4.21B

Not market cap or free float

Reporting institutions by quarter

Counts also change with data coverage and reporting entities; they do not measure net buying. Distinct managers with a live stock row in this CUSIP; totals may include overlapping filings and are not a share of the company.

WEST PHARMACEUTICAL SERVICES INC · Q3 2026

Explore all 431 reporting institutions.

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Sources, coverage & how to read this data

Figures are as reported to the SEC and merged with later amendments where Akkru could match them. Preview limits apply to what is listed, not to the totals, which come from the complete reported data. Nothing is zero-filled: a missing quarter or month is shown as missing.