West Pharmaceutical Services, Inc.
MX ˙ BMV ˙ US9553061055
SecurityMX:WST / West Pharmaceutical Services, Inc.
InstitutionM&t Bank Corp
Latest Disclosed Ownership17,803 shares
Latest Disclosed Value $ 4,462,143
M&t Bank Corp reports 12.97% decrease in ownership of WST / West Pharmaceutical Services, Inc.

On May 12, 2026 - M&t Bank Corp filed a 13F-HR form disclosing ownership of 17,803 shares of West Pharmaceutical Services, Inc. (MX:WST) valued at $4,462,143 USD as of March 31, 2026. The entity filed a previous 13F-HR/A on January 30, 2026 disclosing 20,455 shares of West Pharmaceutical Services, Inc.. This represents a change in shares of -12.97% 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)
2026-05-12 2026-03-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 17,803 -2,652 -12.97 4,462 -20.70 0.0036
2026-01-30 2025-12-31 13F/A-1 WEST PHARMACEUTICAL SVSC COM 955306105 20,455 -170 -0.82 5,628 3.99 0.0181
2026-01-28 2025-12-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 128,638 108,013 12,872 0.0077
2025-11-14 2025-09-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 20,625 -1,189 -5.45 5,411 13.39 0.0182
2025-08-13 2025-06-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 21,814 -56,186 -72.03 4,772 -72.67 0.0164
2025-04-30 2025-03-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 78,000 -1,474 -1.85 17,463 -32.92 0.0636
2025-02-06 2024-12-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 79,474 -1,351 -1.67 26,033 7.31 0.0873
2024-11-19 2024-09-30 13F/A-1 WEST PHARMACEUTICAL SVSC COM 955306105 80,825 273 0.34 24,260 -8.56 0.0798
2024-11-15 2024-09-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 80,825 273 24,260 0.0146
2024-07-31 2024-06-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 80,552 -795 -0.98 26,533 -17.57 0.0906
2024-05-07 2024-03-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 81,347 608 0.75 32,189 13.23 0.1120
2024-02-06 2023-12-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 80,739 -1,031 -1.26 28,429 -7.34 0.1044
2023-11-02 2023-09-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 81,770 54,472 199.55 30,682 193.88 0.1224
2023-08-09 2023-06-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 27,298 -946 -3.35 10,440 6.69 0.0390
2023-05-11 2023-03-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 28,244 -1,638 -5.48 9,786 39.13 0.0379
2023-02-13 2022-12-31 13F/A-1 WEST PHARMACEUTICAL SVSC COM 955306105 29,882 -26,936 -47.41 7,033 -49.70 0.0283
2023-02-13 2022-12-31 13F WESCO INTL COM 955306105 29,869 -26,949 7,029 0.0283
2022-11-17 2022-09-30 13F/A-1 WEST PHARMACEUTICAL SVSC COM 955306105 56,818 1,241 2.23 13,981 -9.38 0.0621
2022-11-14 2022-09-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 56,818 1,241 13,174 0.0112
2022-08-05 2022-06-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 55,577 -4,649 -7.72 15,428 -37.63 0.0727
2022-05-09 2022-03-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 60,226 -3,361 -5.29 24,737 -17.06 0.1093
2022-02-07 2021-12-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 63,587 303 0.48 29,824 11.01 0.1253
2021-10-28 2021-09-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 63,284 383 0.61 26,865 18.93 0.1210
2021-08-13 2021-06-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 62,901 255 0.41 22,588 27.96 0.0992
2021-05-06 2021-03-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 62,646 386 0.62 17,653 0.08 0.0762
2021-02-12 2020-12-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 62,260 1,337 2.19 17,639 5.33 0.0774
2020-11-06 2020-09-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 60,923 -1,244 -2.00 16,747 18.59 0.0822
2020-07-29 2020-06-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 62,167 4,667 8.12 14,122 61.28 0.0757
2020-05-14 2020-03-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 57,500 2,559 4.66 8,756 6.02 0.0518
2020-02-07 2019-12-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 54,941 -1,178 -2.10 8,259 3.77 0.0388
2019-11-12 2019-09-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 56,119 -18,827 -25.12 7,959 -15.14 0.0397
2019-08-12 2019-06-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 74,946 -37 -0.05 9,379 13.51 0.0490
2019-05-15 2019-03-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 74,983 -6,386 -7.85 8,263 3.60 0.0432
2019-02-01 2018-12-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 81,369 1,513 1.89 7,976 -19.11 0.0458
2018-11-09 2018-09-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 79,856 -387 -0.48 9,860 23.76 0.0493
2018-08-10 2018-06-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 80,243 -1,533 -1.87 7,967 10.35 0.0429
2018-05-04 2018-03-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 81,776 1,643 2.05 7,220 -8.68 0.0388
2018-02-06 2017-12-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 80,133 17,957 28.88 7,906 32.10 0.0414
2017-11-13 2017-09-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 62,176 121 0.19 5,985 2.03 0.0325
2017-08-11 2017-06-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 62,055 2,348 3.93 5,866 20.38 0.0346
2017-05-10 2017-03-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 59,707 -4,951 -7.66 4,873 -11.16 0.0294
2017-02-14 2016-12-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 64,658 932 1.46 5,485 15.52 0.0342
2016-11-04 2016-09-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 63,726 522 0.83 4,748 -0.98 0.0303
2016-08-04 2016-06-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 63,204 -3,190 -4.80 4,795 4.17 0.0323
2016-05-11 2016-03-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 66,394 -181 -0.27 4,603 14.85 0.0312
2016-02-12 2015-12-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 66,575 -1,341 -1.97 4,008 9.06 0.0266
2015-11-13 2015-09-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 67,916 -91,762 -57.47 3,675 -60.38 0.0250
2015-08-14 2015-06-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 159,678 -40,313 -20.16 9,275 -22.97 0.0559
2015-05-14 2015-03-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 199,991 -12,117 -5.71 12,041 6.62 0.0751
2015-02-12 2014-12-31 13F WEST PHARMACEUTICAL SVSC COM 955306105 212,108 -6,856 -3.13 11,293 15.23 0.0707
2014-11-14 2014-09-30 13F WEST PHARMACEUTICAL SVSC COM 955306105 218,964 203,962 1,359.57 9,800 1,450.63 0.0687
2014-08-13 2014-06-30 13F WEST PHARMACEUT SVS COMMON 955306105 15,002 805 5.67 632 1.12 0.0264
2014-05-14 2014-03-31 13F WEST PHARMACEUT SVS COMMON 955306105 14,197 -161 -1.12 625 -11.35 0.0259
2014-02-12 2013-12-31 13F WEST PHARMACEUT SVS COMMON 955306105 14,358 -5,686 -28.37 705 -14.44 0.0295
2013-11-13 2013-09-30 13F WEST PHARMACEUT SVS COMMON 955306105 20,044 12,299 158.80 824 51.47 0.0393
2013-07-30 2013-06-30 13F WEST PHARMACEUT SVS COMMON 955306105 7,745 7,745 544 0.0264
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.