Mar 31, 2026 filings. Quarterly 13F reports arrive up to 45 days after quarter end; this register is filed through May 29, 2026.
598 institutional managers reported holding ACM for the quarter ended Mar 31, 2026. Together they hold about 87% of shares outstanding; the top 10 hold 47%. 95 opened new positions; 123 closed out. Complete ranked register from SEC 13F filings.
| manager | shares | % out | value (Mar 31, 2026 close) | change | held since |
|---|---|---|---|---|---|
| BlackRock | 15.76M | 12.20% | $1.34B | added +3.6% | ≤2013 |
| Vanguard Group | 12.28M | 9.51% | $1.04B | unchanged | ≤2013 |
| PRIMECAP Management | 8.65M | 6.69% | $733.2M | unchanged | ≤2013 |
| State Street | 5.04M | 3.90% | $427.5M | unchanged | ≤2013 |
| UBS | 4.91M | 3.80% | $416.1M | added +17.7% | ≤2013 |
| Invesco | 3.58M | 2.77% | $303.2M | trimmed -17.2% | ≤2013 |
| First Trust Advisors LP | 3.03M | 2.34% | $256.6M | trimmed -25.8% | ≤2013 |
| Barrow Hanley Mewhinney & Strauss LLC | 2.85M | 2.21% | $241.9M | added +44.9% | 2020 Q2 |
| Geode Capital | 2.47M | 1.91% | $209.4M | added +1% | ≤2013 |
| Pictet Asset Management Holding SA | 2.13M | 1.65% | $180.5M | trimmed -27.2% | 2020 Q2 |
| FMR (Fidelity) | 2.11M | 1.63% | $178.7M | added +77.7% | ≤2013 |
| Northern Trust | 1.96M | 1.52% | $166.6M | trimmed -3.5% | ≤2013 |
| Morgan Stanley | 1.68M | 1.30% | $142.4M | added +8.9% | ≤2013 |
| Dimensional Fund Advisors | 1.39M | 1.07% | $117.6M | added +6.4% | ≤2013 |
| Impax Asset Management Group plc | 1.38M | 1.07% | $117.2M | trimmed -0.7% | 2023 Q2 |
| BNY Mellon | 1.30M | 1.00% | $110.1M | unchanged | ≤2013 |
| Amundi | 1.23M | 0.95% | $104.0M | added +16.2% | 2021 Q1 |
| Manufacturers Life Insurance Company, THE | 1.22M | 0.94% | $103.6M | added +18.3% | ≤2013 |
| D. E. Shaw | 1.06M | 0.82% | $90.1M | added +195.9% | 2017 Q3 |
| AQR Capital | 1.06M | 0.82% | $90.0M | added +521.4% | 2019 Q2 |
| Lord, Abbett & CO. LLC | 1.01M | 0.78% | $85.2M | added +10.7% | 2025 Q2 |
| Mirae Asset Global Etfs Holdings LTD. | 970.1k | 0.75% | $82.3M | added +7.2% | 2018 Q3 |
| Ninety One UK LTD | 962.4k | 0.74% | $81.6M | trimmed -25.6% | 2024 Q2 |
| Charles Schwab Investment Management | 928.9k | 0.72% | $78.8M | added +2.3% | ≤2013 |
| Goldman Sachs | 797.7k | 0.62% | $67.6M | trimmed -17.5% | ≤2013 |
| Millennium Management | 784.0k | 0.61% | $66.5M | added +107.1% | 2014 Q3 |
| Ameriprise Financial INC | 732.2k | 0.57% | $62.1M | added +31.3% | ≤2013 |
| DekaBank Deutsche Girozentrale | 722.4k | 0.56% | $61.3M | unchanged | 2019 Q4 |
| Citadel Advisors | 714.7k | 0.55% | $60.6M | added +38.8% | 2018 Q1 |
| PFA Pension, Forsikringsaktieselskab | 697.3k | 0.54% | $59.1M | unchanged | 2025 Q4 |
| Deutsche Bank AG\ | 686.3k | 0.53% | $58.2M | trimmed -22.8% | 2013 Q3 |
| Hsbc Holdings PLC | 678.6k | 0.53% | $57.5M | added +15% | 2015 Q1 |
| Renaissance Technologies | 662.3k | 0.51% | $56.2M | added +3.9% | 2022 Q4 |
| Lazard Asset Management LLC | 644.7k | 0.50% | $54.7M | opened | 2026 Q1 |
| Robeco Institutional Asset Management B.v. | 626.9k | 0.48% | $53.2M | added +27.5% | 2021 Q2 |
| Bank OF America CORP /DE/ | 620.6k | 0.48% | $52.6M | trimmed -51.6% | ≤2013 |
| Barclays PLC | 613.7k | 0.47% | $52.0M | added +43.4% | ≤2013 |
| Nordea Investment Management AB | 593.9k | 0.46% | $50.4M | trimmed -6.4% | 2023 Q1 |
| Sandhill Capital Partners LLC | 585.5k | 0.45% | $49.6M | added +24% | 2024 Q4 |
| Voloridge Investment Management | 564.6k | 0.44% | $47.9M | added +117.3% | 2023 Q2 |
| AllianceBernstein | 558.2k | 0.43% | $47.3M | trimmed -63.2% | ≤2013 |
| Nuveen | 508.3k | 0.39% | $43.1M | added +49.8% | 2017 Q4 |
| Two Sigma | 506.6k | 0.39% | $43.0M | added +30.8% | 2022 Q3 |
| Qube Research & Technologies LTD | 441.9k | 0.34% | $37.5M | trimmed -54.7% | 2022 Q1 |
| Allianz Asset Management GmbH | 415.3k | 0.32% | $35.2M | added +982.4% | 2022 Q2 |
| Legal & General Group PLC | 405.3k | 0.31% | $34.4M | trimmed -12.5% | ≤2013 |
| Swiss National Bank | 386.9k | 0.30% | $32.8M | added +6.6% | ≤2013 |
| Russell Investments Group, LTD. | 368.6k | 0.28% | $31.3M | added +31% | 2016 Q4 |
| Rhumbline Advisers | 351.2k | 0.27% | $29.8M | unchanged | ≤2013 |
| BNP Paribas Financial Markets | 349.7k | 0.27% | $29.7M | trimmed -32.4% | 2014 Q1 |
Largest 50 of 598 shown; the full ranked, searchable register is at boothcheck.com/holders/ACM. 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.