Arch Capital Group Ltd.
US ˙ NasdaqGS ˙ BMG0450A1053

SecurityACGL / Arch Capital Group Ltd.
InstitutionHeadlands Technologies LLC
Latest Disclosed Ownership3,618 shares
Latest Disclosed Value $ 347,292
Headlands Technologies LLC reports 81.73% decrease in ownership of ACGL / Arch Capital Group Ltd.

On May 13, 2026 - Headlands Technologies LLC filed a 13F-HR form disclosing ownership of 3,618 shares of Arch Capital Group Ltd. (US:ACGL) valued at $347,292 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 13, 2026 disclosing 19,806 shares of Arch Capital Group Ltd.. This represents a change in shares of -81.73% during the quarter. The current value of the position is $319,614 USD.

Institutional Ownership: 13F and NPORT Filings

The Security and Class in the table below are shown exactly as filed by the investor. We do our best to track continuity of investments through acquisitions, and this will be reflected in the table as changes in names. In addition to descriptive data, performance of the investment is shown over time. To calculate quarterly performance, we first calculate cost basis of the shares purchased during the quarter, then use that to calculate gross profit. Quarterly return is Gross Profit / Starting Portfolio value.

Note that cost basis is calculated and stored in thousands, so small quarterly changes in shares frequently result in a cost basis of zero.

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Disclosed Equity Positions (from 13F/NPORT Filings)
File
Date		 Effective
Date		Form Security Class ID Avg Price
Paid (Est)		 Reported
Shares		 ΔShares ΔShares
(%)		 Reported
Value
(x1000)		 ΔValue
(%)		 Alloc
(%)		 ΔAlloc ΔAlloc (%) Cost Basis
(x1000)		 Unrealized
Gain/Loss
(x1000)
2026-05-13 2026-03-31 13F ARCH CAP GROUP ORD G0450A105 3,618 -16,188 -81.73 347 -81.73 0.0396
2026-02-13 2025-12-31 13F ARCH CAP GROUP ORD G0450A105 19,806 -19,200 -49.22 1,900 -46.34 0.1585
2025-11-12 2025-09-30 13F ARCH CAP GROUP ORD G0450A105 39,006 30,144 340.15 3,539 339.08 0.2826
2025-08-14 2025-06-30 13F ARCH CAP GROUP ORD G0450A105 8,862 -9,412 -51.50 807 -54.13 0.0966
2025-05-09 2025-03-31 13F ARCH CAP GROUP ORD G0450A105 18,274 -11,669 -38.97 1,758 -36.46 0.2003
2025-02-12 2024-12-31 13F ARCH CAP GROUP ORD G0450A105 29,943 9,137 43.92 2,765 18.82 0.2778
2024-11-12 2024-09-30 13F ARCH CAP GROUP ORD G0450A105 20,806 2,139 11.46 2,328 23.58 0.2676
2024-08-07 2024-06-30 13F ARCH CAP GROUP ORD G0450A105 18,667 6,129 48.88 1,883 62.47 0.1998
2024-05-07 2024-03-31 13F ARCH CAP GROUP ORD G0450A105 12,538 141 1.14 1,159 25.98 0.2784
2024-02-02 2023-12-31 13F ARCH CAP GROUP ORD G0450A105 12,397 12,397 921 0.2746
Legend
Shares
The total number of shares held by the institution at the end of the reporting period (the effective date). This is provided in the filing.
Value
The total value of the shares as of the effective date. This is provided in the filing.
Avg. Share Price
The weighted average share price of the shares held by the institution. We use FIFO accounting to determine this price
Class
This is the security class as indicated by the filer. There are a variety of values for this field. Common values include "EC" = equity common, "EP" - equity preferred
Allocation (%)
The percent of the institution's portfolio that this position represents. This is provided in NPORT filings. For 13F filings, we calculate it.
Change in Allocation
The change in allocation from the prior reporting period. This is calculated as current allocation - prior allocation.
Change in Allocation (%)
The percent change in allocation from the prior reporting period. This is calculated as (current allocation - prior allocation) / prior allocation.
Cost Basis
The total cost of the shares held. This is calculated as reported shares * avg. share price
Unrealized Gain/Loss
This is the market value of the position as of the effective date minus the cost basis.