Who owns AON (AON)
Which tracked institutional funds hold AON, how they are positioned, and who is buying versus exiting — from SEC Form 13F-HR filings. See AON company fundamentals →
Ownership as of the 2026-Q1 13F filings. 13F is disclosed up to 45 days after quarter-end, so the most recent quarter fills in over the following weeks.
How the tape is positioned
208 tracked funds added or opened AON while 397 trimmed or exited it between 2025-Q4 and 2026-Q1 — the tape is split. When large holders disagree on a name, the funds moving first are sometimes ahead of the story.
A prompt to read the filings, not a verdict. 13F is a quarter-end snapshot disclosed up to 45 days late; a fund adds or exits for mandate, benchmark, and timing reasons that have nothing to do with a view on the stock. This is a starting question, not a signal to trade.
Conviction spread
AON’s largest tracked holder by dollar value, VANGUARD GROUP INC, sizes it at 0.1% of its own reported 13F book, while the median holder sizes it at 0.2% of theirs — a 0.1pp gap the other way — the median holder sizes AON more heavily than its largest holder by dollar value does.
Book-share is each fund’s reported value in AON divided by its whole reported 13F book, so it is comparable across funds of different sizes and is unaffected by stock splits. A higher share means a fund has committed more of its book to the name — a starting question about conviction, not a verdict or a signal to trade.
Institutional & insider positioning
Between 2025-Q4 and 2026-Q1, across 1252 tracked filers holding AON, 620 increased or opened the position and 578 reduced or closed it; over the same quarter, open-market insider Form 4s were net purchases.
This fuses two public signals for the same quarter — how tracked institutions changed their positions and whether insiders bought or sold in the open market. It describes what was filed; it is a starting question, not a verdict or a signal to trade.
New buyers & exits
Funds opening or closing a position in AON between the 2025-Q4 and 2026-Q1 13F filings, and the largest changes among funds holding it in both. New buyers and exits are counted on fund presence (split-invariant); adds and trims are measured on reported value.
New buyers 63
- VANGUARD CAPITAL MANAGEMENT LLC$4.4B
- VANGUARD PORTFOLIO MANAGEMENT LLC$1.5B
- VANGUARD FIDUCIARY TRUST CO$396M
- BAUPOST GROUP LLC/MA$248M
- Meritage Group LP$220M
- Vanguard Global Advisers, LLC$151M
Full exits 65
- VANGUARD GROUP INC$7.1B
- BERKSHIRE HATHAWAY INC$1.3B
- MOORE CAPITAL MANAGEMENT, LP$49M
- CIBC WORLD MARKETS CORP$24M
- Financiere des Professionnels - Fonds d'investissement inc.$22M
- Caisse de depot et placement du Quebec$18M
Largest adds
- JPMORGAN CHASE & CO$702M
- Wealthspire Advisors, LLC$221M
- PRICE T ROWE ASSOCIATES INC /MD/$209M
- Mitsubishi UFJ Asset Management Co., Ltd.$188M
- AQR CAPITAL MANAGEMENT LLC$164M
- Artisan Partners Limited Partnership$136M
Largest trims
- BlackRock, Inc.$1.0B
- EAGLE CAPITAL MANAGEMENT LLC$651M
- Capital World Investors$619M
- NORGES BANK$491M
- FMR LLC$307M
- STATE STREET CORP$272M
Institutional holders
One row per tracked fund, largest reported value first. “% of value” is the fund’s share of this security’s tracked institutional value — not of shares outstanding. Rows marked stale are from an earlier filing than the security’s latest quarter — that fund is absent from the newest snapshot (position exited, or reported under a different name).
| Fund | Shares | Reported value | % of value | Quarter |
|---|---|---|---|---|
| BlackRock, Inc. trimmed | 14,649,583 | $4.7B | 7.4% | 2026-Q1 |
| VANGUARD CAPITAL MANAGEMENT LLC new | 13,581,756 | $4.4B | 6.8% | 2026-Q1 |
| Capital World Investors trimmed | 11,477,788 | $3.7B | 5.8% | 2026-Q1 |
| STATE STREET CORP added | 9,219,773 | $3.0B | 4.6% | 2026-Q1 |
| MASSACHUSETTS FINANCIAL SERVICES CO /MA/ trimmed | 8,358,097 | $2.8B | 4.3% | 2026-Q1 |
| DODGE & COX added | 8,116,095 | $2.6B | 4.1% | 2026-Q1 |
| MORGAN STANLEY added | 6,374,945 | $2.1B | 3.2% | 2026-Q1 |
| JPMORGAN CHASE & CO added | 5,641,431 | $1.8B | 2.9% | 2026-Q1 |
| GEODE CAPITAL MANAGEMENT, LLC added | 5,244,309 | $1.7B | 2.6% | 2026-Q1 |
| VANGUARD PORTFOLIO MANAGEMENT LLC new | 4,559,035 | $1.5B | 2.3% | 2026-Q1 |
| Bank of New York Mellon Corp trimmed | 3,321,092 | $1.1B | 1.7% | 2026-Q1 |
| DZ BANK AG Deutsche Zentral Genossenschafts Bank, Frankfurt am Main added | 2,948,410 | $952M | 1.5% | 2026-Q1 |
| Independent Franchise Partners LLP added | 2,588,002 | $835M | 1.3% | 2026-Q1 |
| Mitsubishi UFJ Asset Management Co., Ltd. added | 2,516,637 | $812M | 1.3% | 2026-Q1 |
| FARALLON CAPITAL MANAGEMENT LLC trimmed | 2,512,638 | $811M | 1.3% | 2026-Q1 |
| NORTHERN TRUST CORP trimmed | 2,082,105 | $672M | 1.0% | 2026-Q1 |
| NORGES BANK trimmed | 1,665,948 | $665M | 1.0% | 2026-Q1 |
| WCM INVESTMENT MANAGEMENT, LLC trimmed | 1,952,379 | $633M | 1.0% | 2026-Q1 |
| Boston Partners added | 1,955,032 | $631M | 1.0% | 2026-Q1 |
| NEUBERGER BERMAN GROUP LLC added | 1,857,834 | $600M | 0.9% | 2026-Q1 |
| Artisan Partners Limited Partnership added | 1,644,152 | $531M | 0.8% | 2026-Q1 |
| GOLDMAN SACHS GROUP INC added | 1,583,991 | $511M | 0.8% | 2026-Q1 |
| BANK OF AMERICA CORP /DE/ added | 1,582,680 | $511M | 0.8% | 2026-Q1 |
| Veritas Asset Management LLP trimmed | 1,520,277 | $491M | 0.8% | 2026-Q1 |
| Amundi added | 1,502,890 | $485M | 0.8% | 2026-Q1 |
| DIAMOND HILL CAPITAL MANAGEMENT INC trimmed | 1,487,887 | $480M | 0.8% | 2026-Q1 |
| Invesco Ltd. added | 1,448,342 | $467M | 0.7% | 2026-Q1 |
| CHARLES SCHWAB INVESTMENT MANAGEMENT INC added | 1,355,094 | $437M | 0.7% | 2026-Q1 |
| POLEN CAPITAL MANAGEMENT LLC trimmed | 1,354,053 | $437M | 0.7% | 2026-Q1 |
| Legal & General Group Plc trimmed | 1,341,222 | $433M | 0.7% | 2026-Q1 |
| PRICE T ROWE ASSOCIATES INC /MD/ added | 1,280,926 | $413M | 0.6% | 2026-Q1 |
| Mawer Investment Management Ltd. trimmed | 1,277,088 | $412M | 0.6% | 2026-Q1 |
| UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC added | 1,262,123 | $407M | 0.6% | 2026-Q1 |
| DIMENSIONAL FUND ADVISORS LP added | 1,253,769 | $405M | 0.6% | 2026-Q1 |
| VANGUARD FIDUCIARY TRUST CO new | 1,225,563 | $396M | 0.6% | 2026-Q1 |
| LAZARD ASSET MANAGEMENT LLC trimmed | 1,217,243 | $393M | 0.6% | 2026-Q1 |
| Cantillon Capital Management LLC trimmed | 1,095,574 | $354M | 0.6% | 2026-Q1 |
| VIKING GLOBAL INVESTORS LP added | 1,087,114 | $351M | 0.5% | 2026-Q1 |
| AMERIPRISE FINANCIAL INC trimmed | 1,080,672 | $349M | 0.5% | 2026-Q1 |
| Sustainable Growth Advisers, LP trimmed | 1,051,805 | $340M | 0.5% | 2026-Q1 |
| Vontobel Holding Ltd. added | 999,176 | $323M | 0.5% | 2026-Q1 |
| Wealthspire Advisors, LLC added | 984,075 | $318M | 0.5% | 2026-Q1 |
| AQR CAPITAL MANAGEMENT LLC added | 979,443 | $316M | 0.5% | 2026-Q1 |
| Longview Partners (Guernsey) LTD trimmed | 976,263 | $315M | 0.5% | 2026-Q1 |
| UBS Group AG added | 903,928 | $292M | 0.5% | 2026-Q1 |
| Nuveen, LLC added | 851,081 | $275M | 0.4% | 2026-Q1 |
| Capital International Investors trimmed | 807,075 | $261M | 0.4% | 2026-Q1 |
| ARROWSTREET CAPITAL, LIMITED PARTNERSHIP added | 797,418 | $257M | 0.4% | 2026-Q1 |
| BAUPOST GROUP LLC/MA new | 769,000 | $248M | 0.4% | 2026-Q1 |
| FIL Ltd trimmed | 745,959 | $241M | 0.4% | 2026-Q1 |
| First Pacific Advisors, LP added | 703,258 | $227M | 0.4% | 2026-Q1 |
| ROYAL BANK OF CANADA trimmed | 688,130 | $222M | 0.3% | 2026-Q1 |
| Meritage Group LP trimmed | 680,169 | $220M | 0.3% | 2026-Q1 |
| ALTRINSIC GLOBAL ADVISORS LLC added | 660,724 | $213M | 0.3% | 2026-Q1 |
| DEUTSCHE BANK AG\ trimmed | 644,736 | $208M | 0.3% | 2026-Q1 |
| Focus Partners Wealth added | 630,805 | $204M | 0.3% | 2026-Q1 |
| COMGEST GLOBAL INVESTORS S.A.S. added | 628,700 | $203M | 0.3% | 2026-Q1 |
| BARCLAYS PLC added | 600,554 | $194M | 0.3% | 2026-Q1 |
| Swiss National Bank added | 599,260 | $193M | 0.3% | 2026-Q1 |
| OMERS ADMINISTRATION Corp | 567,479 | $183M | 0.3% | 2026-Q1 |
| Fiera Capital Corp added | 550,287 | $178M | 0.3% | 2026-Q1 |
| MANUFACTURERS LIFE INSURANCE COMPANY, THE added | 547,850 | $177M | 0.3% | 2026-Q1 |
| FMR LLC trimmed | 514,593 | $166M | 0.3% | 2026-Q1 |
| USS Investment Management Ltd trimmed | 502,480 | $162M | 0.3% | 2026-Q1 |
| Southpoint Capital Advisors LP trimmed | 500,000 | $161M | 0.3% | 2026-Q1 |
| California Public Employees Retirement System trimmed | 475,942 | $154M | 0.2% | 2026-Q1 |
| National Pension Service added | 475,543 | $153M | 0.2% | 2026-Q1 |
| Vanguard Global Advisers, LLC new | 469,130 | $151M | 0.2% | 2026-Q1 |
| EAGLE CAPITAL MANAGEMENT LLC trimmed | 463,350 | $150M | 0.2% | 2026-Q1 |
| SEI INVESTMENTS CO trimmed | 451,925 | $146M | 0.2% | 2026-Q1 |
| Sumitomo Mitsui Trust Group, Inc. trimmed | 447,301 | $144M | 0.2% | 2026-Q1 |
| ENVESTNET ASSET MANAGEMENT INC added | 423,209 | $137M | 0.2% | 2026-Q1 |
| BLAIR WILLIAM & CO/IL trimmed | 421,605 | $136M | 0.2% | 2026-Q1 |
| C WorldWide Group Holding A/S trimmed | 399,312 | $129M | 0.2% | 2026-Q1 |
| Douglass Winthrop Advisors, LLC added | 394,536 | $127M | 0.2% | 2026-Q1 |
| RHUMBLINE ADVISERS trimmed | 380,644 | $123M | 0.2% | 2026-Q1 |
| BNP PARIBAS FINANCIAL MARKETS trimmed | 368,360 | $119M | 0.2% | 2026-Q1 |
| WELLS FARGO & COMPANY/MN added | 365,706 | $118M | 0.2% | 2026-Q1 |
| VANGUARD ASSET MANAGEMENT, Ltd new | 361,858 | $117M | 0.2% | 2026-Q1 |
| FRANKLIN RESOURCES INC added | 361,315 | $117M | 0.2% | 2026-Q1 |
| HSBC HOLDINGS PLC added | 354,158 | $114M | 0.2% | 2026-Q1 |
| Haverford Trust Co trimmed | 346,117 | $112M | 0.2% | 2026-Q1 |
| NATIXIS ADVISORS, LLC added | 341,937 | $110M | 0.2% | 2026-Q1 |
| DAVENPORT & Co LLC added | 337,041 | $109M | 0.2% | 2026-Q1 |
| Prana Capital Management, LP added | 323,458 | $104M | 0.2% | 2026-Q1 |
| Bowie Capital Management, LLC trimmed | 322,167 | $104M | 0.2% | 2026-Q1 |
| Cryder Capital Partners LLP added | 321,689 | $104M | 0.2% | 2026-Q1 |
| AVIVA PLC trimmed | 310,335 | $100M | 0.2% | 2026-Q1 |
| CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM trimmed | 308,973 | $100M | 0.2% | 2026-Q1 |
| LORD, ABBETT & CO. LLC added | 298,530 | $96M | 0.2% | 2026-Q1 |
| BNP PARIBAS ASSET MANAGEMENT Holding S.A. added | 291,337 | $94M | 0.1% | 2026-Q1 |
| BANK OF MONTREAL /CAN/ trimmed | 288,235 | $93M | 0.1% | 2026-Q1 |
| BRISTOL JOHN W & CO INC /NY/ trimmed | 283,054 | $91M | 0.1% | 2026-Q1 |
| DekaBank Deutsche Girozentrale | 275,444 | $90M | 0.1% | 2026-Q1 |
| CapitalatWork S.A. new | 272,003 | $88M | 0.1% | 2026-Q1 |
| CANADA PENSION PLAN INVESTMENT BOARD added | 269,059 | $87M | 0.1% | 2026-Q1 |
| VANGUARD GROUP INC added | 20,170,441 | $7.1B | 11.1% | 2025-Q4 stale |
| HPS Investment Partners, LLC trimmed | 4,243,321 | $1.5B | 2.4% | 2025-Q2 stale |
| BERKSHIRE HATHAWAY INC trimmed | 3,602,995 | $1.3B | 2.0% | 2025-Q4 stale |
| TWO SIGMA ADVISERS, LP added | 724,400 | $258M | 0.4% | 2025-Q2 stale |
Ownership over time
Tracked institutional holder count and total shares held by filing quarter (independent scales). The curated-era tail and any mid-ingest latest quarter are handled honestly — a partial quarter is not drawn as a collapse.
Reading this table
Funds hold the same stock for different reasons — an index fund “holds” almost everything, an active manager sizes a name to a mandate and a benchmark, and each fund entered at its own price and time. Because 13F is filed up to 45 days after quarter-end, every row is a backward-looking snapshot; a manager may have traded since. Share-class siblings (a company’s A and C shares) are rolled up to one line so a dual-class name is never double-counted. Compare like-for-like. A large holder is not an endorsement, and a fund exiting is not a warning — this is a starting question, not a verdict.
About 13F filings
A Form 13F is a quarterly disclosure that institutional investment managers with over $100 million in US-listed equities must file with the SEC. In plain English: it is a snapshot of the long stock positions a fund held at the end of a quarter. It covers long US-listed equities only — not short positions, options, cash, or private holdings — and the funds shown are the large sample we track, not the complete 13F universe.