West Pharmaceutical Services, Inc.

The full register, from 13F filings

The Register tab above is hand research: a dozen holders, each traced to the filing it came from. This asks the same question of the whole market for the quarter ended 31-mar-2026, where 743 managers reported a position. Broad where the research is deep, and shallow in the ways a 13F always is.

Built from 13F filings, which report US listed, long, US custodied positions only. A register from this source is a floor rather than a level: a holder's true position can be far larger, as BlackRock's ASML stake shows at 1.28m shares in a 13F against 26.3m in its 13G/A. Holdings held through derivatives, outside US custody, or below a manager's reporting obligation do not appear. Where a holder is marked as a family, its total sums several separate filing entities and describes something no single filing describes; the constituent entities and their share counts are listed so the total can be checked. That roll-up can legitimately exceed the family's own Schedule 13G, because a 13G is filed by one legal entity: Vanguard reports Alphabet through ten advisory entities, and The Vanguard Group Inc itself reported zero after its January 2026 disaggregation.

What a reader needs to know to read these numbers

• Holdings side: West's marquee equity-method affiliate is Daikyo Seiko, Ltd. (Japan), held at 49% since 1 Nov 2019 (up from an earlier ~25% interest, increased for $85.1 million cash plus $4.9 million in treasury stock per the FY2019 10-K). This is confirmed as CURRENT, not stale, by both the FY2025 10-K and the Q2 2026 10-Q (whose Subsequent Event note on a 14 Jul 2026 agreement restates the 49% figure directly). West also holds a 49% interest in each of four Mexico-based equity-method affiliates (The West Company Mexico, Aluplast, Pharma Tap, Pharma Rubber), grouped into one holdings row here. Neither Daikyo nor the Mexico affiliates can be individually valued: West's Note 7 'Affiliated Companies' discloses only a single combined 'Equity method affiliates' carrying value ($207.1 million at 30 Jun 2026, $208.3 million at FY2025 end, $194.9 million at FY2024 end) covering all five entities together, with no per-entity split in any filing found (10-Ks for FY2019, FY2023, FY2025, and the Q2 2026 10-Q were all read in this task). Per the brief's rule against assigning a combined balance to one investee, both holdings rows carry value_usd: null, with the combined figures recorded here instead. Separately, West carries a small, unnamed 'Non-equity method affiliates' bucket at cost less impairment ($0.6 million at Q2 2026, down from $4.0 million at FY2025 end after a $3.5 million impairment in H1 2026, and $7.2 million at FY2024 end); no individual investee name or percentage was found for this bucket in any filing searched, so no row was created for it (see unknowns). No joint venture, non-marketable equity securities, or unconsolidated-entity language was found anywhere in the Q2 2026 10-Q (search terms 'joint venture', 'unconsolidated', and 'non-marketable' each returned zero hits); West's own filings use 'affiliated companies' as the umbrella term for everything covered here.
• West's Exhibit 21.1 subsidiaries list was not separately fetched in this task because Note 7 'Affiliated Companies' already discloses an ownership-percentage table directly (Daikyo and the four Mexico affiliates, all at 49%), which is the information Exhibit 21 would otherwise be checked for; no further equity-method or minority investees beyond these five were found in the 10-K or 10-Q text searched.
• T. Rowe Price family: both registrants specifically flagged in the brief were swept and both hold, as two separate rows per the brief's rule (T. Rowe Price Investment Management, Inc., CIK 0001897612, 1,805,019 shares, is the LARGER of the two, ahead of T. Rowe Price Associates, Inc., CIK 0000080255, at 524,652 shares). Both file values in thousands on their 13F information tables; both figures here have been corrected from thousands to whole dollars and cross-checked against the ~$359/share price seen on every other Q2 2026 row.
• Capital Group family: all 11 registrants were checked (8 that hold securities, 3 that filed Form 13F-NT with no holdings for Q2 2026). Only one, Capital Research Global Investors (CIK 0001422848), holds West stock (609,221 shares); the other 7 holding registrants were checked directly against CUSIP 955306105 and found at zero. This is reported as a single-entity row, not a summed family roll-up, because only one entity in the family actually holds.
• Vanguard family: parent CIK 0000102909 (The Vanguard Group, Inc.) filed Form 13F-NT for Q2 2026, a notice carrying no holdings, so per the brief the successor entities ARE the position and were summed (not substituted). 7 of 8 checked successor entities hold; Vanguard National Trust Co (CIK 0001984256) was checked directly and holds zero West shares. The 2026 DEF 14A's 5%-owner table cites a Schedule 13G/A filed by Vanguard on 31 Oct 2025 (ownership as of 30 Sep 2025) at 9,704,948 shares (13.49%), somewhat larger than and about 9 months staler than the itemized Q2 2026 13F family sum used here (9,363,324 shares); the proxy figure is preserved on the Vanguard register row as a reconciliation per the brief's preference for the fresher, itemized figure. BlackRock shows the same pattern: DEF 14A cites a Schedule 13G/A filed 24 Apr 2025 (ownership as of 31 Mar 2025) at 6,066,852 shares (8.40%), smaller and staler than the Q2 2026 13F figure used here (6,651,784 shares); also preserved as a reconciliation on the BlackRock row.
• Implied per-share price check across every Q2 2026 institutional row: all fall in a tight $354.66-$359.05 band (Vanguard family, BlackRock, Fidelity, State Street, Artisan Partners, BNY Mellon, Generation Investment Management, T. Rowe Price Investment Management, Morgan Stanley, Invesco, Capital Group and T. Rowe Price Associates all at approximately $359.00-$359.05; Geode at approximately $357.60; JPMorgan at approximately $354.66), a strong independent cross-check that every row is the same CUSIP 955306105 common-stock instrument as of the same 30 Jun 2026 date, with no units-in-thousands or share-class errors. The live intraday price used for market_cap_usd is $352.79 (Yahoo Finance chart API, close 19 Aug 2026), about 7 weeks after the 13F date and consistent with a modest decline from the ~$359 level seen in the 13F data.
• Self-gate computed from this final file, following the chart's own arithmetic (members at full value, an aggregate reduced only by members that roll into it; here no register row carries rolls_up_into, so every row, including the directors/officers aggregate, counts at full value): 15 register rows, 38,918,653 total shares (Vanguard family 9,363,324 + BlackRock 6,651,784 + Fidelity/FMR 3,574,816 + State Street 3,348,698 + Artisan Partners 2,411,792 + BNY Mellon 2,043,823 + Generation Investment Management 2,028,322 + Geode 1,903,279 + T. Rowe Price Investment Management 1,805,019 + Morgan Stanley 1,582,546 + JPMorgan 1,164,527 + Invesco 1,009,852 + Capital Group 609,221 + T. Rowe Price Associates 524,652 + directors/officers aggregate 896,998), against shares_outstanding 70,375,762 = 55.30% of the company. This is just above the brief's suggested 25-45% band and essentially at its 55% flag line. The implied-price check above rules out a units or share-class mismatch (every row prices within a tight ~$4.50 band of the same ~$359 figure), and no holder appears twice (14 distinct institutional families plus one non-overlapping insider aggregate), so the total is reported as a genuine finding: West's institutional ownership is unusually concentrated among a comparatively small number of large holders (this project's own 31 Mar 2026 register snapshot, data/registers/WST.json, shows 743 total 13F filers reporting 71,082,443 aggregate shares, slightly ABOVE that period's shares outstanding, which is normal for 13F data due to overlapping managed-account reporting but confirms institutional ownership of West is very high in total), rather than evidence of a double-counted holder or mixed instrument basis.
• Current price used for market_cap_usd is a live intraday quote (Yahoo Finance chart API, $352.79, close 19 Aug 2026) multiplied by the 20 Jul 2026 cover-page share count from the Q2 2026 10-Q (70,375,762 shares); the two dates do not match exactly (about one month apart) because no single source carries both a current price and a current share count.
• No em dashes used anywhere in this file's text fields per the brief.