Mar 31, 2026 filings. Quarterly 13F reports arrive up to 45 days after quarter end; this register is filed through May 29, 2026.
391 institutional managers reported holding CWST for the quarter ended Mar 31, 2026. Reported positions total over 95% of shares outstanding; the top 10 hold 52%. 61 opened new positions; 58 closed out. Complete ranked register from SEC 13F filings.
| manager | shares | % out | value (Mar 31, 2026 close) | change | held since |
|---|---|---|---|---|---|
| BlackRock | 9.05M | 14.24% | $718.3M | unchanged | ≤2013 |
| Vanguard Group | 6.70M | 10.54% | $531.6M | added +1.7% | ≤2013 |
| Conestoga Capital Advisors, LLC | 2.80M | 4.41% | $222.6M | added +1% | 2019 Q3 |
| Wasatch Advisors LP | 2.58M | 4.06% | $205.0M | trimmed -31.4% | 2024 Q1 |
| State Street | 2.39M | 3.76% | $189.7M | added +3.6% | ≤2013 |
| Capital Research Global Investors | 2.33M | 3.67% | $185.0M | trimmed -6.3% | 2023 Q4 |
| Capital International Investors | 1.95M | 3.07% | $155.0M | trimmed -2.3% | 2024 Q2 |
| T. Rowe Price Investment Management, INC. | 1.70M | 2.67% | $134.9M | added +545.3% | 2023 Q2 |
| Invesco | 1.65M | 2.60% | $131.3M | trimmed -38.8% | ≤2013 |
| Geode Capital | 1.55M | 2.44% | $123.3M | added +0.9% | ≤2013 |
| William Blair Investment Management, LLC | 1.26M | 1.98% | $99.8M | trimmed -14.4% | 2018 Q3 |
| Silvercrest Asset Management Group LLC | 1.25M | 1.97% | $99.4M | trimmed -7.2% | 2019 Q1 |
| UBS | 1.23M | 1.93% | $97.3M | added +6.3% | ≤2013 |
| Wellington Management | 1.21M | 1.91% | $96.2M | trimmed -7.3% | 2020 Q4 |
| Morgan Stanley | 1.20M | 1.88% | $94.9M | trimmed -12.3% | ≤2013 |
| Geneva Capital Management LLC | 1.16M | 1.83% | $92.3M | trimmed -8.1% | 2023 Q1 |
| Clearbridge Investments, LLC | 1.14M | 1.80% | $90.6M | added +52.1% | 2024 Q3 |
| Earnest Partners LLC | 1.13M | 1.78% | $90.0M | trimmed -2.5% | 2018 Q1 |
| Dimensional Fund Advisors | 1.07M | 1.68% | $84.7M | added +3% | ≤2013 |
| Goldman Sachs | 1.05M | 1.65% | $83.4M | added +16.8% | ≤2013 |
| Neuberger Berman Group LLC | 953.8k | 1.50% | $75.7M | trimmed -8.8% | 2018 Q1 |
| Pictet Asset Management Holding SA | 924.4k | 1.46% | $73.4M | trimmed -6.7% | 2020 Q3 |
| Nomura Asset Management International INC. | 835.4k | 1.31% | $66.3M | trimmed -11.4% | 2025 Q4 |
| Westfield Capital Management CO LP | 822.5k | 1.29% | $65.3M | trimmed -50.6% | 2022 Q4 |
| Ameriprise Financial INC | 780.3k | 1.23% | $62.0M | added +2.1% | 2018 Q3 |
| Voya Investment Management LLC | 724.4k | 1.14% | $57.5M | added +5.5% | 2017 Q2 |
| Allspring Global Investments Holdings, LLC | 721.9k | 1.14% | $57.3M | added +3.2% | 2021 Q4 |
| Bamco INC /NY/ | 718.5k | 1.13% | $57.0M | added +61% | 2025 Q4 |
| Northern Trust | 711.8k | 1.12% | $56.5M | unchanged | ≤2013 |
| Charles Schwab Investment Management | 652.7k | 1.03% | $51.8M | trimmed -3% | ≤2013 |
| Brown Advisory INC | 649.5k | 1.02% | $51.6M | trimmed -2% | 2022 Q2 |
| Loomis Sayles & CO L P | 608.7k | 0.96% | $48.3M | trimmed -6.5% | 2019 Q3 |
| BNP Paribas Financial Markets | 607.2k | 0.95% | $48.2M | trimmed -10.5% | 2014 Q2 |
| TimesSquare Capital Management, LLC | 574.2k | 0.90% | $45.6M | trimmed -3.9% | 2019 Q1 |
| London CO OF Virginia | 532.7k | 0.84% | $42.3M | trimmed -2.6% | 2023 Q2 |
| Fred Alger Management, LLC | 526.7k | 0.83% | $41.8M | added +17.4% | 2019 Q1 |
| SEI Investments CO | 525.1k | 0.83% | $41.7M | trimmed -5.9% | 2015 Q3 |
| Point72 | 463.9k | 0.73% | $36.8M | opened | 2026 Q1 |
| Schroder Investment Management Group | 448.0k | 0.70% | $35.6M | opened | 2026 Q1 |
| Bank OF America CORP /DE/ | 438.9k | 0.69% | $34.8M | trimmed -28.6% | ≤2013 |
| Woodline Partners LP | 415.4k | 0.65% | $33.0M | added +781.3% | 2025 Q4 |
| BNY Mellon | 396.2k | 0.62% | $31.5M | trimmed -2.9% | ≤2013 |
| Capital Group (American Funds) | 392.1k | 0.62% | $31.1M | opened | 2026 Q1 |
| Select Equity Group | 392.0k | 0.62% | $31.1M | added +4.7% | 2021 Q1 |
| Fifth Third Bancorp | 387.5k | 0.61% | $30.8M | added +5715.3% | 2019 Q3 |
| Boston Trust Walden CORP | 384.8k | 0.61% | $30.5M | added +23.5% | 2025 Q4 |
| Franklin Resources | 345.8k | 0.54% | $27.5M | trimmed -11% | 2024 Q1 |
| Ranger Investment Management, L.p. | 341.7k | 0.54% | $27.1M | trimmed -0.7% | 2022 Q3 |
| DF Dent & CO INC | 327.6k | 0.52% | $26.0M | trimmed -4.6% | 2023 Q4 |
| Global Alpha Capital Management LTD. | 325.8k | 0.51% | $25.9M | trimmed -0.8% | 2023 Q4 |
Largest 50 of 391 shown; the full ranked, searchable register is at boothcheck.com/holders/CWST. 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.