Who owns Arch Capital Group (ACGLO)
Which tracked institutional funds hold ACGLO, how they are positioned, and who is buying versus exiting — from SEC Form 13F-HR filings. See ACGLO 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
182 tracked funds added or opened ACGLO while 203 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
ACGLO’s largest tracked holder by dollar value, BlackRock, Inc., sizes it at 0.0% of its own reported 13F book, while the median holder sizes it at 0.1% of theirs — a 0.0pp gap the other way — the median holder sizes ACGLO more heavily than its largest holder by dollar value does.
Book-share is each fund’s reported value in ACGLO 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 852 tracked filers holding ACGLO, 408 increased or opened the position and 512 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 ACGLO 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 31
- Caisse de depot et placement du Quebec$32M
- United Super Pty Ltd in its capacity as Trustee for the Construction & Building Unions Superannuation Fund$22M
- CAPITOLIS LIQUID GLOBAL MARKETS LLC$11M
- Cornerstone Advisors, LLC$9M
- GW HENSSLER & ASSOCIATES LTD$8M
- WINTON GROUP Ltd$5M
Full exits 72
- NATIXIS ADVISORS, LLC$224M
- Amundi$188M
- Thrivent Financial for Lutherans$126M
- Egerton Capital (UK) LLP$107M
- LORD, ABBETT & CO. LLC$89M
- Clark Capital Management Group, Inc.$69M
Largest adds
- BlackRock, Inc.$543M
- ARROWSTREET CAPITAL, LIMITED PARTNERSHIP$253M
- Invesco Ltd.$100M
- High Ground Investment Management LLP$81M
- JANE STREET GROUP, LLC$68M
- Allspring Global Investments Holdings, LLC$61M
Largest trims
- UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC$296M
- FIRST TRUST ADVISORS LP$209M
- AQR CAPITAL MANAGEMENT LLC$129M
- Champlain Investment Partners, LLC$85M
- Artisan Partners Limited Partnership$80M
- BAMCO INC /NY/$63M
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 |
|---|---|---|---|---|
| BlackRock, Inc. added | 30,220,703 | $2.9B | 10.8% | 2026-Q2 |
| VANGUARD CAPITAL MANAGEMENT LLC trimmed | 22,221,428 | $2.2B | 8.0% | 2026-Q2 |
| Artisan Partners Limited Partnership trimmed | 21,595,895 | $2.1B | 7.8% | 2026-Q2 |
| STATE STREET CORP added | 16,251,212 | $1.6B | 5.8% | 2026-Q2 |
| BAMCO INC /NY/ trimmed | 15,872,450 | $1.5B | 5.7% | 2026-Q2 |
| VANGUARD PORTFOLIO MANAGEMENT LLC trimmed | 14,527,363 | $1.4B | 5.2% | 2026-Q2 |
| WCM INVESTMENT MANAGEMENT, LLC trimmed | 11,973,574 | $1.2B | 4.3% | 2026-Q2 |
| GEODE CAPITAL MANAGEMENT, LLC trimmed | 10,507,722 | $1.0B | 3.8% | 2026-Q2 |
| JPMORGAN CHASE & CO added | 6,991,580 | $686M | 2.5% | 2026-Q2 |
| Invesco Ltd. added | 4,947,084 | $480M | 1.8% | 2026-Q2 |
| NORGES BANK trimmed | 4,675,717 | $454M | 1.7% | 2026-Q2 |
| ARROWSTREET CAPITAL, LIMITED PARTNERSHIP added | 4,493,790 | $436M | 1.6% | 2026-Q2 |
| MORGAN STANLEY added | 4,359,144 | $423M | 1.6% | 2026-Q2 |
| NORTHERN TRUST CORP trimmed | 4,281,588 | $416M | 1.5% | 2026-Q2 |
| DIMENSIONAL FUND ADVISORS LP added | 4,218,184 | $409M | 1.5% | 2026-Q2 |
| Allspring Global Investments Holdings, LLC added | 4,139,902 | $408M | 1.5% | 2026-Q2 |
| Madison Asset Management, LLC trimmed | 3,799,789 | $369M | 1.4% | 2026-Q2 |
| ROYAL BANK OF CANADA trimmed | 3,495,371 | $339M | 1.3% | 2026-Q2 |
| MARSHFIELD ASSOCIATES added | 3,331,135 | $323M | 1.2% | 2026-Q2 |
| Legal & General Group Plc trimmed | 3,119,937 | $303M | 1.1% | 2026-Q2 |
| GOLDMAN SACHS GROUP INC added | 3,015,755 | $293M | 1.1% | 2026-Q2 |
| Polar Capital Holdings Plc trimmed | 2,980,000 | $289M | 1.1% | 2026-Q2 |
| PRINCIPAL FINANCIAL GROUP INC trimmed | 2,868,362 | $278M | 1.0% | 2026-Q2 |
| High Ground Investment Management LLP added | 2,612,372 | $254M | 0.9% | 2026-Q2 |
| JONES FINANCIAL COMPANIES LLLP added | 2,269,585 | $221M | 0.8% | 2026-Q2 |
| COOKE & BIELER LP trimmed | 2,219,448 | $215M | 0.8% | 2026-Q2 |
| ENVESTNET ASSET MANAGEMENT INC trimmed | 2,200,819 | $214M | 0.8% | 2026-Q2 |
| CHARLES SCHWAB INVESTMENT MANAGEMENT INC added | 2,177,713 | $211M | 0.8% | 2026-Q2 |
| Boston Partners added | 2,156,551 | $209M | 0.8% | 2026-Q2 |
| Robeco Institutional Asset Management B.V. added | 2,048,973 | $199M | 0.7% | 2026-Q2 |
| VANGUARD FIDUCIARY TRUST CO trimmed | 1,940,803 | $188M | 0.7% | 2026-Q2 |
| Swedbank AB added | 1,888,385 | $183M | 0.7% | 2026-Q2 |
| SEI INVESTMENTS CO added | 1,839,517 | $179M | 0.7% | 2026-Q2 |
| Nuveen, LLC trimmed | 1,775,060 | $172M | 0.6% | 2026-Q2 |
| GQG Partners LLC added | 1,717,256 | $167M | 0.6% | 2026-Q2 |
| Bank of New York Mellon Corp trimmed | 1,593,928 | $155M | 0.6% | 2026-Q2 |
| FMR LLC trimmed | 1,582,311 | $154M | 0.6% | 2026-Q2 |
| BRANDES INVESTMENT PARTNERS, LP trimmed | 1,518,218 | $147M | 0.5% | 2026-Q2 |
| BANK OF AMERICA CORP /DE/ trimmed | 1,500,979 | $146M | 0.5% | 2026-Q2 |
| HSBC HOLDINGS PLC added | 1,442,557 | $141M | 0.5% | 2026-Q2 |
| DEUTSCHE BANK AG\ trimmed | 1,439,416 | $140M | 0.5% | 2026-Q2 |
| AMERICAN CENTURY COMPANIES INC added | 1,364,898 | $132M | 0.5% | 2026-Q2 |
| AQR CAPITAL MANAGEMENT LLC trimmed | 1,353,793 | $131M | 0.5% | 2026-Q2 |
| UBS Group AG trimmed | 1,350,323 | $131M | 0.5% | 2026-Q2 |
| BNP PARIBAS ASSET MANAGEMENT Holding S.A. trimmed | 1,237,549 | $120M | 0.4% | 2026-Q2 |
| FIDUCIARY MANAGEMENT INC /WI/ trimmed | 1,225,226 | $119M | 0.4% | 2026-Q2 |
| BARCLAYS PLC trimmed | 1,210,288 | $117M | 0.4% | 2026-Q2 |
| WELLINGTON MANAGEMENT GROUP LLP added | 1,189,970 | $115M | 0.4% | 2026-Q2 |
| WELLS FARGO & COMPANY/MN trimmed | 1,165,234 | $113M | 0.4% | 2026-Q2 |
| BROWN ADVISORY INC trimmed | 1,153,081 | $112M | 0.4% | 2026-Q2 |
| FRANKLIN RESOURCES INC added | 1,123,099 | $109M | 0.4% | 2026-Q2 |
| BNP PARIBAS FINANCIAL MARKETS added | 1,109,264 | $108M | 0.4% | 2026-Q2 |
| Maren Capital LLC trimmed | 1,057,571 | $103M | 0.4% | 2026-Q2 |
| ASSETMARK, INC added | 1,050,118 | $102M | 0.4% | 2026-Q2 |
| Swiss National Bank trimmed | 979,800 | $95M | 0.4% | 2026-Q2 |
| Sumitomo Mitsui Trust Group, Inc. trimmed | 934,282 | $91M | 0.3% | 2026-Q2 |
| JANE STREET GROUP, LLC added | 932,724 | $91M | 0.3% | 2026-Q2 |
| Mitsubishi UFJ Asset Management Co., Ltd. added | 853,186 | $83M | 0.3% | 2026-Q2 |
| STIFEL FINANCIAL CORP trimmed | 852,350 | $83M | 0.3% | 2026-Q2 |
| Capital International Investors trimmed | 804,728 | $78M | 0.3% | 2026-Q2 |
| TWO SIGMA INVESTMENTS, LP trimmed | 787,208 | $76M | 0.3% | 2026-Q2 |
| Vanguard Global Advisers, LLC trimmed | 758,434 | $74M | 0.3% | 2026-Q2 |
| National Pension Service added | 719,128 | $70M | 0.3% | 2026-Q2 |
| California Public Employees Retirement System trimmed | 713,917 | $69M | 0.3% | 2026-Q2 |
| AMERIPRISE FINANCIAL INC trimmed | 705,273 | $68M | 0.3% | 2026-Q2 |
| Clearbridge Investments, LLC added | 704,752 | $68M | 0.3% | 2026-Q2 |
| VANGUARD ASSET MANAGEMENT, Ltd added | 681,091 | $66M | 0.2% | 2026-Q2 |
| Davis Asset Management, L.P. | 650,000 | $63M | 0.2% | 2026-Q2 |
| RHUMBLINE ADVISERS trimmed | 632,424 | $61M | 0.2% | 2026-Q2 |
| RAYMOND JAMES FINANCIAL INC added | 597,918 | $58M | 0.2% | 2026-Q2 |
| CITIGROUP INC added | 593,549 | $58M | 0.2% | 2026-Q2 |
| BANK OF MONTREAL /CAN/ trimmed | 537,813 | $52M | 0.2% | 2026-Q2 |
| CANADA PENSION PLAN INVESTMENT BOARD trimmed | 534,416 | $52M | 0.2% | 2026-Q2 |
| GENERAL AMERICAN INVESTORS CO INC | 530,200 | $51M | 0.2% | 2026-Q2 |
| PFA Pension, Forsikringsaktieselskab added | 525,283 | $51M | 0.2% | 2026-Q2 |
| PRICE T ROWE ASSOCIATES INC /MD/ added | 523,807 | $51M | 0.2% | 2026-Q2 |
| Port Capital LLC trimmed | 496,956 | $48M | 0.2% | 2026-Q2 |
| Mariner, LLC added | 493,580 | $48M | 0.2% | 2026-Q2 |
| CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM added | 491,428 | $48M | 0.2% | 2026-Q2 |
| STOREBRAND ASSET MANAGEMENT AS added | 486,641 | $47M | 0.2% | 2026-Q2 |
| Russell Investments Group, Ltd. trimmed | 477,379 | $46M | 0.2% | 2026-Q2 |
| Smith Group Asset Management, LLC added | 442,710 | $43M | 0.2% | 2026-Q2 |
| FIRST TRUST ADVISORS LP trimmed | 442,606 | $43M | 0.2% | 2026-Q2 |
| ANCHOR CAPITAL ADVISORS LLC trimmed | 439,823 | $43M | 0.2% | 2026-Q2 |
| Man Group plc trimmed | 416,273 | $40M | 0.1% | 2026-Q2 |
| Allianz Asset Management GmbH added | 412,451 | $40M | 0.1% | 2026-Q2 |
| SUSQUEHANNA FUNDAMENTAL INVESTMENTS, LLC added | 409,682 | $40M | 0.1% | 2026-Q2 |
| NEW YORK STATE COMMON RETIREMENT FUND trimmed | 386,488 | $38M | 0.1% | 2026-Q2 |
| WEALTH ENHANCEMENT ADVISORY SERVICES, LLC added | 385,850 | $38M | 0.1% | 2026-Q2 |
| COMMERCE BANK trimmed | 372,974 | $36M | 0.1% | 2026-Q2 |
| Champlain Investment Partners, LLC trimmed | 370,745 | $36M | 0.1% | 2026-Q2 |
| ALLIANCEBERNSTEIN L.P. trimmed | 369,839 | $36M | 0.1% | 2026-Q2 |
| CONFLUENCE INVESTMENT MANAGEMENT LLC trimmed | 333,833 | $32M | 0.1% | 2026-Q2 |
| Caisse de depot et placement du Quebec new | 330,400 | $32M | 0.1% | 2026-Q2 |
| Aberdeen Group plc added | 315,799 | $31M | 0.1% | 2026-Q2 |
| Arbejdsmarkedets Tillaegspension added | 314,200 | $30M | 0.1% | 2026-Q2 |
| AVIVA PLC trimmed | 307,042 | $30M | 0.1% | 2026-Q2 |
| FJARDE AP-FONDEN /FOURTH SWEDISH NATIONAL PENSION FUND added | 306,700 | $30M | 0.1% | 2026-Q2 |
| Gladstone Capital Management LLP trimmed | 306,665 | $30M | 0.1% | 2026-Q2 |
| MILLENNIUM MANAGEMENT LLC trimmed | 305,902 | $30M | 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.