Mar 31, 2026 filings. Quarterly 13F reports arrive up to 45 days after quarter end; this register is filed through May 29, 2026.
730 institutional managers reported holding WST for the quarter ended Mar 31, 2026. Reported positions total over 95% of shares outstanding; the top 10 hold 47%. 79 opened new positions; 134 closed out. Complete ranked register from SEC 13F filings.
| manager | shares | % out | value (Mar 31, 2026 close) | change | held since |
|---|---|---|---|---|---|
| Vanguard Group | 9.51M | 13.14% | $2.38B | unchanged | ≤2013 |
| BlackRock | 6.84M | 9.44% | $1.71B | added +3.6% | ≤2013 |
| State Street | 3.29M | 4.55% | $825.9M | added +1.3% | ≤2013 |
| Artisan Partners | 2.66M | 3.67% | $666.4M | trimmed -6.8% | 2017 Q3 |
| BNY Mellon | 2.47M | 3.41% | $618.3M | trimmed -7.4% | ≤2013 |
| T. Rowe Price Investment Management, INC. | 2.34M | 3.23% | $586.8M | added +195.3% | 2022 Q3 |
| Generation Investment Management LLP (focused) | 2.24M | 3.10% | $562.6M | added +43.7% | 2025 Q2 |
| Geode Capital | 1.91M | 2.64% | $479.5M | added +2.3% | ≤2013 |
| Morgan Stanley | 1.46M | 2.01% | $365.6M | trimmed -4.8% | ≤2013 |
| Brown Advisory INC | 1.34M | 1.85% | $336.2M | trimmed -31% | 2017 Q1 |
| Longview Partners (Guernsey) LTD (focused) | 1.32M | 1.82% | $329.8M | added +16.3% | 2025 Q3 |
| APG Asset Management N.v. | 1.27M | 1.75% | $317.8M | added +5.7% | 2019 Q4 |
| FMR (Fidelity) | 1.25M | 1.73% | $313.4M | added +1039.7% | 2018 Q3 |
| UBS | 1.18M | 1.63% | $295.4M | added +1.9% | ≤2013 |
| Invesco | 1.06M | 1.46% | $264.8M | added +16.2% | ≤2013 |
| Kayne Anderson Rudnick Investment Management LLC | 858.3k | 1.19% | $215.2M | trimmed -10.1% | 2016 Q3 |
| TD Asset Management INC | 769.0k | 1.06% | $192.8M | added +26.9% | 2015 Q1 |
| Northern Trust | 731.3k | 1.01% | $183.4M | added +0.7% | ≤2013 |
| Goldman Sachs | 727.6k | 1.00% | $182.4M | added +65.4% | ≤2013 |
| VAN ECK Associates CORP | 713.6k | 0.99% | $178.9M | unchanged | 2020 Q2 |
| Jacobs Levy Equity Management, INC | 705.3k | 0.97% | $176.9M | added +10.3% | 2025 Q1 |
| ProShare Advisors LLC | 660.1k | 0.91% | $165.5M | added +12.5% | ≤2013 |
| Amundi | 644.1k | 0.89% | $161.5M | added +85.4% | 2017 Q4 |
| Findlay Park Partners LLP | 616.8k | 0.85% | $154.6M | trimmed -7.5% | 2022 Q4 |
| Capital Research Global Investors | 604.0k | 0.83% | $151.4M | opened | 2026 Q1 |
| Charles Schwab Investment Management | 554.3k | 0.77% | $139.0M | added +2.1% | ≤2013 |
| Epoch Investment Partners, INC. | 545.0k | 0.75% | $136.7M | added +7.9% | 2020 Q3 |
| SEI Investments CO | 529.3k | 0.73% | $132.7M | trimmed -10.6% | 2015 Q4 |
| T. Rowe Price | 526.4k | 0.73% | $132.0M | added +55.2% | ≤2013 |
| Arrowstreet Capital | 510.5k | 0.70% | $128.0M | added +69.9% | 2025 Q1 |
| Legal & General Group PLC | 506.5k | 0.70% | $127.0M | added +0.8% | 2014 Q3 |
| Dimensional Fund Advisors | 461.5k | 0.64% | $115.7M | added +5.5% | ≤2013 |
| Gates Foundation Trust (focused) | 444.5k | 0.61% | $111.5M | unchanged | 2025 Q1 |
| Deutsche Bank AG\ | 418.9k | 0.58% | $105.0M | added +12.3% | 2013 Q3 |
| Viking Global | 416.9k | 0.58% | $104.5M | added +41.3% | 2025 Q4 |
| Nuveen | 409.0k | 0.56% | $102.5M | added +1.2% | 2019 Q2 |
| American Century Companies INC | 399.7k | 0.55% | $100.2M | trimmed -10.3% | 2019 Q4 |
| State Farm Mutual Automobile Insurance CO | 388.2k | 0.54% | $97.3M | unchanged | 2015 Q2 |
| Bank OF America CORP /DE/ | 381.8k | 0.53% | $95.7M | trimmed -28.2% | ≤2013 |
| Royal Bank OF Canada | 377.6k | 0.52% | $94.7M | trimmed -15.1% | ≤2013 |
| Liontrust Investment Partners LLP | 366.2k | 0.51% | $91.8M | unchanged | 2024 Q2 |
| BNP Paribas Financial Markets | 358.5k | 0.49% | $89.9M | added +37.9% | ≤2013 |
| Barclays PLC | 349.1k | 0.48% | $87.5M | added +145.5% | ≤2013 |
| Citadel Advisors | 323.6k | 0.45% | $81.1M | added +31.7% | ≤2013 |
| Jane Street | 305.1k | 0.42% | $76.5M | added +38.9% | 2019 Q3 |
| Worldquant Millennium Advisors LLC | 268.1k | 0.37% | $67.2M | added +1789% | 2025 Q1 |
| AQR Capital | 266.9k | 0.37% | $66.9M | trimmed -48.4% | 2014 Q4 |
| Riverbridge Partners LLC | 261.4k | 0.36% | $65.6M | trimmed -17.9% | 2017 Q2 |
| Rhumbline Advisers | 259.2k | 0.36% | $65.0M | trimmed -4.8% | ≤2013 |
| Stonehage Fleming Financial Services Holdings LTD | 254.8k | 0.35% | $63.9M | opened | 2026 Q1 |
Largest 50 of 730 shown; the full ranked, searchable register is at boothcheck.com/holders/WST. Related filers are grouped using the filings' own included-manager declarations. Historically, several managers opening new positions in the same quarter said almost nothing about the quarter that followed (59,118 cases since 2013). A filed record, not a forecast. Nothing here is investment advice.