West Pharmaceutical Services, Inc.
MX ˙ BMV ˙ US9553061055
SecurityMX:WST / West Pharmaceutical Services, Inc.
InstitutionProShare Advisors LLC
Latest Disclosed Ownership660,084 shares
Latest Disclosed Value $ 165,443,452
ProShare Advisors LLC reports 12.48% increase in ownership of WST / West Pharmaceutical Services, Inc.

On April 24, 2026 - ProShare Advisors LLC filed a 13F-HR form disclosing ownership of 660,084 shares of West Pharmaceutical Services, Inc. (MX:WST) valued at $165,443,452 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 6, 2026 disclosing 586,847 shares of West Pharmaceutical Services, Inc.. This represents a change in shares of 12.48% during the quarter.

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)
2026-04-24 2026-03-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 660,084 73,237 12.48 165,443 2.46 0.2450
2026-02-06 2025-12-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 586,847 -25,773 -4.21 161,465 0.47 0.2850
2025-11-06 2025-09-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 612,620 -125,748 -17.03 160,709 -0.52 0.3363
2025-08-07 2025-06-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 738,368 235,272 46.76 161,555 43.43 0.3224
2025-05-08 2025-03-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 503,096 -74,872 -12.95 112,633 -40.51 0.2542
2025-02-14 2024-12-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 577,968 -533,588 -48.00 189,319 -43.26 0.4327
2024-11-14 2024-09-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 1,111,556 644,750 138.12 333,645 116.99 0.8178
2024-08-13 2024-06-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 466,806 -33,856 -6.76 153,761 -22.39 0.4114
2024-05-08 2024-03-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 500,662 61,247 13.94 198,117 28.04 0.5267
2024-02-14 2023-12-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 439,415 -49,350 -10.10 154,727 -15.63 0.4728
2023-11-13 2023-09-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 488,765 7,889 1.64 183,390 -0.29 0.5718
2023-08-10 2023-06-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 480,876 -193,264 -28.67 183,921 -21.26 0.5334
2023-05-26 2023-03-31 13F/A-1 WEST PHARMACEUTICAL SVSC COM 955306105 674,140 -27,520 -3.92 233,569 41.44 0.7138
2023-05-12 2023-03-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 674,140 -27,520 233,569 0.7427
2023-02-02 2022-12-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 701,660 182,459 35.14 165,136 29.25 0.5798
2022-11-07 2022-09-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 519,201 28,876 5.89 127,765 -13.82 0.4903
2022-08-01 2022-06-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 490,325 67,170 15.87 148,260 -14.69 0.4917
2022-05-10 2022-03-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 423,155 54,851 14.89 173,793 0.61 0.3733
2022-02-08 2021-12-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 368,304 -17,537 -4.55 172,739 5.45 0.3390
2021-11-12 2021-09-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 385,841 -34,603 -8.23 163,805 8.49 0.4602
2021-08-13 2021-06-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 420,444 31,745 8.17 150,981 37.85 0.4413
2021-05-14 2021-03-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 388,699 373,227 2,412.27 109,528 2,398.93 0.3444
2021-02-09 2020-12-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 15,472 1,245 8.75 4,383 12.07 0.0163
2020-11-13 2020-09-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 14,227 -893 -5.91 3,911 13.86 0.0181
2020-08-03 2020-06-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 15,120 -80,651 -84.21 3,435 -76.44 0.0183
2020-05-15 2020-03-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 95,771 -22,879 -19.28 14,581 -18.25 0.1048
2020-02-12 2019-12-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 118,650 -4,533 -3.68 17,837 2.10 0.0826
2019-11-12 2019-09-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 123,183 4,289 3.61 17,470 17.41 0.0978
2019-08-13 2019-06-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 118,894 9,820 9.00 14,880 23.79 0.0890
2019-05-15 2019-03-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 109,074 25,093 29.88 12,020 46.00 0.0719
2019-02-14 2018-12-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 83,981 -3,905 -4.44 8,233 -24.13 0.0576
2018-11-14 2018-09-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 87,886 -64 -0.07 10,851 24.25 0.0737
2018-08-13 2018-06-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 87,950 283 0.32 8,733 12.83 0.0585
2018-05-14 2018-03-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 87,667 -27,236 -23.70 7,740 -31.73 0.0504
2018-02-14 2017-12-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 114,903 8,783 8.28 11,337 10.98 0.0786
2017-11-13 2017-09-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 106,120 -12,932 -10.86 10,215 -9.22 0.0939
2017-08-11 2017-06-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 119,052 4,255 3.71 11,253 20.11 0.1121
2017-05-12 2017-03-31 13F/A-2 WEST PHARMACEUTICAL SVSC COM 955306105 114,797 17,617 18.13 9,369 13.65 0.0980
2017-05-08 2017-03-31 13F/A-1 WEST PHARMACEUTICAL SVSC COM 955306105 114,797 0 9,369 0.0980
2017-04-25 2017-03-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 114,797 9,369
2017-02-13 2016-12-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 97,180 34,952 56.17 8,244 77.83 0.0913
2016-11-10 2016-09-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 62,228 24,794 66.23 4,636 63.24 0.0647
2016-08-12 2016-06-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 37,434 -536 -1.41 2,840 7.90 0.0366
2016-05-06 2016-03-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 37,970 14,934 64.83 2,632 89.76 0.0362
2016-02-05 2015-12-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 23,036 4,879 26.87 1,387 41.10 0.0168
2015-11-06 2015-09-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 18,157 2,265 14.25 983 6.50 0.0138
2015-08-11 2015-06-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 15,892 -4,714 -22.88 923 -25.62 0.0128
2015-05-08 2015-03-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 20,606 20,606 0.00 1,241 0.0146
2015-01-30 2014-12-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 0 -32,148 -100.00 0 -100.00
2014-11-06 2014-09-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 32,148 -7,841 -19.61 1,439 -14.70 0.0191
2014-08-08 2014-06-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 39,989 -34,079 -46.01 1,687 -48.30 0.0219
2014-05-07 2014-03-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 74,068 65,950 812.39 3,263 719.85 0.0408
2014-02-04 2013-12-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 8,118 -38,914 -82.74 398 -79.43 0.0059
2013-11-07 2013-09-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 47,032 22,869 94.64 1,935 13.96 0.0459
2013-07-25 2013-06-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 24,163 24,163 1,698 0.0333
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.