West Pharmaceutical Services, Inc.
US ˙ NYSE ˙ US9553061055

SecurityWST / West Pharmaceutical Services, Inc.
InstitutionMan Group plc
Latest Disclosed Ownership79,649 shares
Latest Disclosed Value $ 19,963,225
Man Group plc reports 18.30% increase in ownership of WST / West Pharmaceutical Services, Inc.

On May 15, 2026 - Man Group plc filed a 13F-HR form disclosing ownership of 79,649 shares of West Pharmaceutical Services, Inc. (US:WST) valued at $19,963,225 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 17, 2026 disclosing 67,328 shares of West Pharmaceutical Services, Inc.. This represents a change in shares of 18.30% during the quarter. The current value of the position is $25,193,775 USD.

Institutional Ownership: 13F and NPORT Filings

The Security and Class in the table below are shown exactly as filed by the investor. We do our best to track continuity of investments through acquisitions, and this will be reflected in the table as changes in names. In addition to descriptive data, performance of the investment is shown over time. To calculate quarterly performance, we first calculate cost basis of the shares purchased during the quarter, then use that to calculate gross profit. Quarterly return is Gross Profit / Starting Portfolio value.

Note that cost basis is calculated and stored in thousands, so small quarterly changes in shares frequently result in a cost basis of zero.

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Disclosed Equity Positions (from 13F/NPORT Filings)
File
Date		 Effective
Date		Form Security Class ID Avg Price
Paid (Est)		 Reported
Shares		 ΔShares ΔShares
(%)		 Reported
Value
(x1000)		 ΔValue
(%)		 Alloc
(%)		 ΔAlloc ΔAlloc (%) Cost Basis
(x1000)		 Unrealized
Gain/Loss
(x1000)
2026-05-15 2026-03-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 79,649 12,321 18.30 19,963 7.77 0.0362
2026-02-17 2025-12-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 67,328 -35,157 -34.30 18,525 -31.10 0.0315
2025-11-14 2025-09-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 102,485 2,507 2.51 26,885 22.90 0.0467
2025-08-14 2025-06-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 99,978 69,069 223.46 21,875 216.16 0.0417
2025-05-15 2025-03-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 30,909 14,547 88.91 6,920 29.11 0.0175
2025-02-14 2024-12-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 16,362 -7,046 -30.10 5,360 -23.73 0.0141
2024-11-14 2024-09-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 23,408 -180,847 -88.54 7,026 -89.56 0.0183
2024-08-14 2024-06-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 204,255 178,428 690.86 67,280 558.31 0.1699
2024-05-15 2024-03-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 25,827 -123,831 -82.74 10,220 -80.61 0.0258
2024-02-14 2023-12-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 149,658 52,698 -42.42 0.1467
2023-11-14 2023-09-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 91,523 -4.84 0.2836
2023-08-14 2023-06-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 251,465 96,178 231.09 0.2967
2023-05-15 2023-03-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 29,049 124.92 0.1033
2023-02-14 2022-12-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 54,877 -23,486 -29.97 12,915 -33.03 0.0463
2022-11-14 2022-09-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 78,363 19,284 -70.65 0.0895
2022-08-15 2022-06-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 65,711 -22.62 0.2785
2022-05-16 2022-03-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 206,773 35,092 20.44 84,924 5.47 0.2954
2022-02-14 2021-12-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 171,681 130,413 316.01 80,520 359.59 0.2589
2021-11-15 2021-09-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 41,268 15,759 61.78 17,520 91.25 0.0615
2021-08-16 2021-06-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 25,509 -161 -0.63 9,161 26.64 0.0323
2021-05-17 2021-03-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 25,670 3,239 14.44 7,234 13.83 0.0318
2021-02-16 2020-12-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 22,431 -31,923 -58.73 6,355 -57.47 0.0279
2020-11-16 2020-09-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 54,354 8,739 19.16 14,942 44.20 0.0588
2020-08-14 2020-06-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 45,615 -19,411 -29.85 10,362 4.67 0.0523
2020-05-15 2020-03-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 65,026 2,656 4.26 9,900 5.58 0.0641
2020-02-18 2019-12-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 62,370 15,300 32.50 9,377 40.48 0.0308
2019-11-14 2019-09-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 47,070 -30,454 -39.28 6,675 -31.20 0.0248
2019-08-14 2019-06-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 77,524 23,604 43.78 9,702 63.28 0.0351
2019-05-15 2019-03-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 53,920 6,343 13.33 5,942 27.40 0.0225
2019-02-14 2018-12-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 47,577 -74,725 -61.10 4,664 -69.11 0.0208
2018-11-14 2018-09-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 122,302 9,501 8.42 15,100 34.82 0.0552
2018-08-14 2018-06-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 112,801 56,133 99.06 11,200 123.87 0.0461
2018-05-15 2018-03-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 56,668 56,668 5,003 0.0229
Legend
Shares
The total number of shares held by the institution at the end of the reporting period (the effective date). This is provided in the filing.
Value
The total value of the shares as of the effective date. This is provided in the filing.
Avg. Share Price
The weighted average share price of the shares held by the institution. We use FIFO accounting to determine this price
Class
This is the security class as indicated by the filer. There are a variety of values for this field. Common values include "EC" = equity common, "EP" - equity preferred
Allocation (%)
The percent of the institution's portfolio that this position represents. This is provided in NPORT filings. For 13F filings, we calculate it.
Change in Allocation
The change in allocation from the prior reporting period. This is calculated as current allocation - prior allocation.
Change in Allocation (%)
The percent change in allocation from the prior reporting period. This is calculated as (current allocation - prior allocation) / prior allocation.
Cost Basis
The total cost of the shares held. This is calculated as reported shares * avg. share price
Unrealized Gain/Loss
This is the market value of the position as of the effective date minus the cost basis.