Mar 31, 2026 filings. Quarterly 13F reports arrive up to 45 days after quarter end; this register is filed through May 29, 2026.
1,222 institutional managers reported holding AON for the quarter ended Mar 31, 2026. Together they hold about 85% of shares outstanding; the top 10 hold 43%. 124 opened new positions; 166 closed out. Complete ranked register from SEC 13F filings.
| manager | shares | % out | value (Mar 31, 2026 close) | change | held since |
|---|---|---|---|---|---|
| Vanguard Group | 20.33M | 9.44% | $6.56B | added +0.6% | ≤2013 |
| BlackRock | 16.15M | 7.50% | $5.21B | trimmed -0.5% | ≤2013 |
| Capital Group (American Funds) | 11.48M | 5.33% | $3.71B | trimmed -6.3% | 2018 Q3 |
| State Street | 9.22M | 4.28% | $2.98B | unchanged | ≤2013 |
| MFS Investment Management | 8.36M | 3.88% | $2.70B | trimmed -2.2% | ≤2013 |
| Dodge & Cox | 8.12M | 3.77% | $2.62B | added +3.4% | 2025 Q3 |
| Morgan Stanley | 6.37M | 2.96% | $2.06B | added +14.4% | ≤2013 |
| Geode Capital | 5.24M | 2.44% | $1.69B | added +2% | ≤2013 |
| BNY Mellon | 3.32M | 1.54% | $1.07B | trimmed -4.5% | ≤2013 |
| DZ Bank AG Deutsche Zentral Genossenschafts Bank, Frankfurt am Main | 2.95M | 1.37% | $951.8M | added +22.1% | 2016 Q4 |
| Mitsubishi UFJ Asset Management CO., LTD. | 2.63M | 1.22% | $849.4M | added +36.9% | ≤2013 |
| Independent Franchise Partners LLP (focused) | 2.59M | 1.20% | $835.5M | added +22.3% | 2020 Q3 |
| Farallon Capital | 2.51M | 1.17% | $811.2M | trimmed -5.7% | 2020 Q2 |
| UBS | 2.17M | 1.01% | $699.3M | added +5.2% | ≤2013 |
| Northern Trust | 2.08M | 0.97% | $672.2M | trimmed -0.8% | ≤2013 |
| Boston Partners | 1.96M | 0.91% | $631.2M | added +19.6% | 2014 Q4 |
| WCM Investment Management | 1.95M | 0.91% | $630.3M | trimmed -1.7% | 2020 Q3 |
| Neuberger Berman Group LLC | 1.86M | 0.86% | $599.8M | added +3% | ≤2013 |
| Artisan Partners | 1.64M | 0.76% | $530.8M | added +47.1% | ≤2013 |
| Goldman Sachs | 1.58M | 0.73% | $511.4M | added +12.4% | ≤2013 |
| Bank OF America CORP /DE/ | 1.58M | 0.73% | $510.9M | added +16.3% | ≤2013 |
| Veritas Asset Management LLP (focused) | 1.52M | 0.71% | $490.8M | trimmed -23.7% | 2024 Q1 |
| Amundi | 1.50M | 0.70% | $485.2M | added +23.5% | 2017 Q4 |
| Diamond Hill Capital Management INC | 1.49M | 0.69% | $480.3M | trimmed -6.8% | 2024 Q3 |
| Invesco | 1.49M | 0.69% | $479.9M | added +11.3% | ≤2013 |
| Charles Schwab Investment Management | 1.36M | 0.63% | $437.5M | added +3.4% | ≤2013 |
| Polen Capital | 1.35M | 0.63% | $437.1M | trimmed -26.7% | 2020 Q3 |
| Legal & General Group PLC | 1.34M | 0.62% | $433.0M | trimmed -0.7% | 2016 Q4 |
| T. Rowe Price | 1.28M | 0.59% | $413.5M | added +121.5% | ≤2013 |
| Mawer Investment Management LTD. | 1.28M | 0.59% | $412.3M | trimmed -13.6% | ≤2013 |
| Dimensional Fund Advisors | 1.25M | 0.58% | $404.8M | added +20.5% | ≤2013 |
| Lazard Asset Management LLC | 1.22M | 0.56% | $393.0M | trimmed -5.4% | 2014 Q2 |
| Cantillon Capital Management LLC (focused) | 1.10M | 0.51% | $353.7M | trimmed -11.9% | 2016 Q4 |
| Viking Global | 1.09M | 0.51% | $351.0M | added +38.7% | 2025 Q3 |
| Ameriprise Financial INC | 1.08M | 0.50% | $348.9M | trimmed -2.5% | ≤2013 |
| Sustainable Growth Advisers, LP | 1.05M | 0.49% | $339.6M | trimmed -13.9% | 2019 Q2 |
| Vontobel Holding LTD. | 999.2k | 0.46% | $322.6M | added +31.4% | 2021 Q2 |
| Wealthspire Advisors, LLC | 984.1k | 0.46% | $317.7M | added +259.7% | 2015 Q4 |
| AQR Capital | 979.8k | 0.46% | $316.3M | added +127.8% | 2014 Q4 |
| Longview Partners (Guernsey) LTD (focused) | 976.3k | 0.45% | $315.2M | trimmed -11.7% | ≤2013 |
| Nuveen | 851.1k | 0.40% | $274.8M | added +5.3% | 2023 Q4 |
| Capital International Investors | 807.1k | 0.38% | $260.6M | trimmed -35.7% | 2016 Q4 |
| Arrowstreet Capital | 797.4k | 0.37% | $257.4M | added +74.7% | 2025 Q1 |
| Baupost Group (focused) | 769.0k | 0.36% | $248.3M | opened | 2026 Q1 |
| FIL LTD | 746.0k | 0.35% | $240.8M | trimmed -15.6% | 2018 Q3 |
| First Manhattan CO. LLC. | 726.3k | 0.34% | $234.5M | added +6.5% | ≤2013 |
| Royal Bank OF Canada | 688.1k | 0.32% | $222.2M | trimmed -27.9% | ≤2013 |
| Meritage Group LP (focused) | 680.2k | 0.32% | $219.6M | opened | 2026 Q1 |
| Altrinsic Global Advisors LLC (focused) | 660.7k | 0.31% | $213.3M | added +1.5% | 2024 Q2 |
| BNP Paribas Financial Markets | 659.7k | 0.31% | $213.0M | added +39% | 2024 Q4 |
Largest 50 of 1,222 shown; the full ranked, searchable register is at boothcheck.com/holders/AON. 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.