Who owns Acadian Asset Management (AAMI)
Which tracked institutional funds hold AAMI, how they are positioned, and who is buying versus exiting — from SEC Form 13F-HR filings. See AAMI company fundamentals →
Ownership as of the 2026-Q2 13F filings (latest filed 2026-09-22). 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
112 tracked funds added or opened AAMI while 39 trimmed or exited it between 2026-Q1 and 2026-Q2 — 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
AAMI’s largest tracked holder by dollar value, PAULSON & CO. INC., sizes it at 16.2% of its own reported 13F book, while the median holder sizes it at 0.0% of theirs — a 16.2pp conviction gap — its largest holder concentrates the name more heavily than the typical one.
Book-share is each fund’s reported value in AAMI 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 2026-Q1 and 2026-Q2, across 279 tracked filers holding AAMI, 159 increased or opened the position and 126 reduced or closed it; over the same quarter, open-market insider Form 4s were net sales.
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 AAMI between the 2026-Q1 and 2026-Q2 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 25
- Driehaus Capital Management LLC$56M
- Avantyr Capital Partners, LP$55M
- Jupiter Topco LLC$11M
- Ghisallo Capital Management LLC$6M
- Informed Momentum Co LLC$6M
- MACKENZIE FINANCIAL CORP$3M
Full exits 21
- SG Americas Securities, LLC$33M
- GW&K Investment Management, LLC$20M
- JANUS HENDERSON GROUP PLC$11M
- Man Group plc$6M
- BRIGHTLIGHT CAPITAL MANAGEMENT LP$5M
- Karl Kapital LLC$5M
Largest adds
- BlackRock, Inc.$169M
- Invesco Ltd.$77M
- GEODE CAPITAL MANAGEMENT, LLC$29M
- Woodline Partners LP$25M
- Empyrean Capital Partners, LP$22M
- STATE STREET CORP$22M
Largest trims
- Impax Asset Management Group plc$20M
- JACOBS LEVY EQUITY MANAGEMENT, INC$6M
- North Reef Capital Management LP$6M
- Qube Research & Technologies Ltd$6M
- DEUTSCHE BANK AG\$4M
- PAULSON & CO. INC.$3M
Institutional holders
One row per tracked fund, most shares held first (every row is from one quarter; reported value breaks ties). “% of value” is the fund’s share of this security’s tracked institutional value — not of shares outstanding.
| Fund | Shares | Reported value | % of value | Quarter |
|---|---|---|---|---|
| PAULSON & CO. INC. trimmed | 5,843,282 | $418M | 17.2% | 2026-Q2 |
| BlackRock, Inc. added | 4,486,535 | $321M | 13.2% | 2026-Q2 |
| JENNISON ASSOCIATES LLC trimmed | 1,526,570 | $109M | 4.5% | 2026-Q2 |
| Invesco Ltd. added | 1,376,531 | $98M | 4.1% | 2026-Q2 |
| Empyrean Capital Partners, LP trimmed | 1,308,000 | $94M | 3.9% | 2026-Q2 |
| STATE STREET CORP added | 1,224,388 | $88M | 3.6% | 2026-Q2 |
| VANGUARD CAPITAL MANAGEMENT LLC added | 1,176,511 | $84M | 3.5% | 2026-Q2 |
| GEODE CAPITAL MANAGEMENT, LLC added | 969,724 | $69M | 2.9% | 2026-Q2 |
| DIMENSIONAL FUND ADVISORS LP added | 911,667 | $65M | 2.7% | 2026-Q2 |
| Woodline Partners LP added | 883,540 | $63M | 2.6% | 2026-Q2 |
| VANGUARD PORTFOLIO MANAGEMENT LLC trimmed | 813,352 | $58M | 2.4% | 2026-Q2 |
| Driehaus Capital Management LLC new | 788,901 | $56M | 2.3% | 2026-Q2 |
| Avantyr Capital Partners, LP new | 767,793 | $55M | 2.3% | 2026-Q2 |
| MORGAN STANLEY added | 623,422 | $45M | 1.8% | 2026-Q2 |
| SOROS FUND MANAGEMENT LLC trimmed | 610,248 | $44M | 1.8% | 2026-Q2 |
| Nuveen, LLC added | 602,378 | $43M | 1.8% | 2026-Q2 |
| FEDERATED HERMES, INC. added | 574,597 | $41M | 1.7% | 2026-Q2 |
| Allspring Global Investments Holdings, LLC added | 553,623 | $40M | 1.6% | 2026-Q2 |
| TWO SIGMA INVESTMENTS, LP added | 523,939 | $37M | 1.5% | 2026-Q2 |
| Azora Capital LP added | 496,005 | $35M | 1.5% | 2026-Q2 |
| CHARLES SCHWAB INVESTMENT MANAGEMENT INC trimmed | 403,342 | $29M | 1.2% | 2026-Q2 |
| Systematic Alpha Investments, LLC | 370,108 | $26M | 1.1% | 2026-Q2 |
| Impax Asset Management Group plc trimmed | 350,000 | $25M | 1.0% | 2026-Q2 |
| NORTHERN TRUST CORP added | 303,111 | $22M | 0.9% | 2026-Q2 |
| Boston Trust Walden Corp trimmed | 268,707 | $19M | 0.8% | 2026-Q2 |
| AQR CAPITAL MANAGEMENT LLC added | 254,068 | $18M | 0.7% | 2026-Q2 |
| HEALTHCARE OF ONTARIO PENSION PLAN TRUST FUND added | 249,082 | $18M | 0.7% | 2026-Q2 |
| GOLDMAN SACHS GROUP INC added | 244,568 | $17M | 0.7% | 2026-Q2 |
| FMR LLC added | 231,204 | $17M | 0.7% | 2026-Q2 |
| WILLIAM BLAIR INVESTMENT MANAGEMENT, LLC trimmed | 207,796 | $15M | 0.6% | 2026-Q2 |
| Bank of New York Mellon Corp added | 204,912 | $15M | 0.6% | 2026-Q2 |
| PRINCIPAL FINANCIAL GROUP INC trimmed | 196,988 | $14M | 0.6% | 2026-Q2 |
| FIRST TRUST ADVISORS LP added | 194,899 | $14M | 0.6% | 2026-Q2 |
| UBS Group AG trimmed | 193,687 | $14M | 0.6% | 2026-Q2 |
| VANGUARD FIDUCIARY TRUST CO added | 190,801 | $14M | 0.6% | 2026-Q2 |
| Allianz Asset Management GmbH trimmed | 161,768 | $11M | 0.5% | 2026-Q2 |
| JACOBS LEVY EQUITY MANAGEMENT, INC trimmed | 151,793 | $11M | 0.4% | 2026-Q2 |
| Jupiter Topco LLC new | 151,546 | $11M | 0.4% | 2026-Q2 |
| ARROWSTREET CAPITAL, LIMITED PARTNERSHIP trimmed | 149,259 | $11M | 0.4% | 2026-Q2 |
| BANK OF AMERICA CORP /DE/ trimmed | 133,241 | $10M | 0.4% | 2026-Q2 |
| JUPITER ASSET MANAGEMENT LTD | 131,673 | $9M | 0.4% | 2026-Q2 |
| Public Sector Pension Investment Board trimmed | 130,897 | $9M | 0.4% | 2026-Q2 |
| Universal- Beteiligungs- und Servicegesellschaft mbH added | 105,367 | $8M | 0.3% | 2026-Q2 |
| UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC added | 103,504 | $7M | 0.3% | 2026-Q2 |
| AMERICAN CENTURY COMPANIES INC added | 95,664 | $7M | 0.3% | 2026-Q2 |
| Vident Advisory, LLC added | 92,774 | $7M | 0.3% | 2026-Q2 |
| North Reef Capital Management LP trimmed | 86,596 | $6M | 0.3% | 2026-Q2 |
| Ghisallo Capital Management LLC new | 85,379 | $6M | 0.3% | 2026-Q2 |
| Cannell & Spears LLC trimmed | 84,330 | $6M | 0.2% | 2026-Q2 |
| Walleye Capital LLC added | 82,585 | $6M | 0.2% | 2026-Q2 |
| Informed Momentum Co LLC trimmed | 82,424 | $6M | 0.2% | 2026-Q2 |
| JPMORGAN CHASE & CO trimmed | 81,372 | $6M | 0.2% | 2026-Q2 |
| CREDIT AGRICOLE S A added | 80,000 | $6M | 0.2% | 2026-Q2 |
| AMERIPRISE FINANCIAL INC trimmed | 78,746 | $6M | 0.2% | 2026-Q2 |
| FRANKLIN RESOURCES INC added | 74,727 | $5M | 0.2% | 2026-Q2 |
| ALGERT GLOBAL LLC trimmed | 74,067 | $5M | 0.2% | 2026-Q2 |
| ENVESTNET ASSET MANAGEMENT INC added | 70,624 | $5M | 0.2% | 2026-Q2 |
| Legal & General Group Plc added | 68,012 | $5M | 0.2% | 2026-Q2 |
| Linden Thomas Advisory Services, LLC added | 66,756 | $5M | 0.2% | 2026-Q2 |
| RHUMBLINE ADVISERS trimmed | 65,048 | $5M | 0.2% | 2026-Q2 |
| VICTORY CAPITAL MANAGEMENT INC added | 63,862 | $5M | 0.2% | 2026-Q2 |
| Trexquant Investment LP added | 62,669 | $4M | 0.2% | 2026-Q2 |
| CITADEL ADVISORS LLC trimmed | 61,940 | $4M | 0.2% | 2026-Q2 |
| Qube Research & Technologies Ltd trimmed | 55,830 | $4M | 0.2% | 2026-Q2 |
| THORNBURG INVESTMENT MANAGEMENT INC added | 55,757 | $4M | 0.2% | 2026-Q2 |
| Swiss National Bank trimmed | 55,626 | $4M | 0.2% | 2026-Q2 |
| Boston Partners trimmed | 52,688 | $4M | 0.2% | 2026-Q2 |
| MILLENNIUM MANAGEMENT LLC trimmed | 51,885 | $4M | 0.2% | 2026-Q2 |
| Rockefeller Capital Management L.P. added | 50,010 | $4M | 0.1% | 2026-Q2 |
| CITIGROUP INC added | 43,839 | $3M | 0.1% | 2026-Q2 |
| EFG International AG trimmed | 40,664 | $3M | 0.1% | 2026-Q2 |
| MACKENZIE FINANCIAL CORP added | 40,105 | $3M | 0.1% | 2026-Q2 |
| Creative Planning added | 39,983 | $3M | 0.1% | 2026-Q2 |
| STATE OF WISCONSIN INVESTMENT BOARD added | 38,688 | $3M | 0.1% | 2026-Q2 |
| STATE BOARD OF ADMINISTRATION OF FLORIDA RETIREMENT SYSTEM trimmed | 38,525 | $3M | 0.1% | 2026-Q2 |
| CWA Asset Management Group, LLC added | 37,227 | $3M | 0.1% | 2026-Q2 |
| SEI INVESTMENTS CO added | 36,368 | $3M | 0.1% | 2026-Q2 |
| PDT Partners, LLC added | 36,197 | $3M | 0.1% | 2026-Q2 |
| RAYMOND JAMES FINANCIAL INC added | 36,172 | $3M | 0.1% | 2026-Q2 |
| ALLIANCEBERNSTEIN L.P. trimmed | 35,887 | $2M | 0.1% | 2026-Q2 |
| Redhawk Wealth Advisors, Inc. trimmed | 35,281 | $3M | 0.1% | 2026-Q2 |
| CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM added | 34,481 | $2M | 0.1% | 2026-Q2 |
| Engineers Gate Manager LP trimmed | 34,006 | $2M | 0.1% | 2026-Q2 |
| Kendall Capital Management trimmed | 33,985 | $2M | 0.1% | 2026-Q2 |
| D. E. Shaw & Co., Inc. trimmed | 33,743 | $2M | 0.1% | 2026-Q2 |
| Y-Intercept (Hong Kong) Ltd added | 32,525 | $2M | 0.1% | 2026-Q2 |
| Aquatic Capital Management LLC added | 31,941 | $2M | 0.1% | 2026-Q2 |
| RENAISSANCE TECHNOLOGIES LLC trimmed | 31,651 | $2M | 0.1% | 2026-Q2 |
| HUSSMAN STRATEGIC ADVISORS, INC. trimmed | 31,500 | $2M | 0.1% | 2026-Q2 |
| DEUTSCHE BANK AG\ trimmed | 29,706 | $2M | 0.1% | 2026-Q2 |
| BNP PARIBAS FINANCIAL MARKETS trimmed | 29,343 | $2M | 0.1% | 2026-Q2 |
| Squarepoint Ops LLC added | 29,242 | $2M | 0.1% | 2026-Q2 |
| Diametric Capital, LP added | 27,813 | $2M | 0.1% | 2026-Q2 |
| PRUDENTIAL FINANCIAL INC added | 27,496 | $2M | 0.1% | 2026-Q2 |
| XTX Topco Ltd added | 26,825 | $2M | 0.1% | 2026-Q2 |
| ROYCE & ASSOCIATES LP trimmed | 26,705 | $2M | 0.1% | 2026-Q2 |
| WELLS FARGO & COMPANY/MN added | 26,112 | $2M | 0.1% | 2026-Q2 |
| Weiss Asset Management LP new | 25,675 | $2M | 0.1% | 2026-Q2 |
| Russell Investments Group, Ltd. trimmed | 24,691 | $2M | 0.1% | 2026-Q2 |
| JONES FINANCIAL COMPANIES LLLP added | 23,899 | $2M | 0.1% | 2026-Q2 |
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.