拱門資本集團有限公司
US ˙ NasdaqGS ˙ BMG0450A1053

SecurityACGL / Arch Capital Group Ltd.
InstitutionGilbert & Cook, Inc.
Latest Disclosed Ownership2,502 shares
Latest Disclosed Value $ 240,167
Gilbert & Cook, Inc. reports 21.64% decrease in ownership of ACGL / Arch Capital Group Ltd.

On May 5, 2026 - Gilbert & Cook, Inc. filed a 13F-HR form disclosing ownership of 2,502 shares of Arch Capital Group Ltd. (US:ACGL) valued at $240,167 USD as of March 31, 2026. The entity filed a previous 13F-HR on January 7, 2026 disclosing 3,193 shares of Arch Capital Group Ltd.. This represents a change in shares of -21.64% during the quarter. The current value of the position is $221,027 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)
2026-05-05 2026-03-31 13F ARCH CAP GROUP ORD G0450A105 2,502 -691 -21.64 240 -21.57 0.0310
2026-01-07 2025-12-31 13F ARCH CAP GROUP ORD G0450A105 3,193 -135 -4.06 306 1.66 0.0385
2025-11-12 2025-09-30 13F ARCH CAP GROUP ORD G0450A105 3,328 -2,395 -41.85 302 -42.23 0.0388
2025-08-05 2025-06-30 13F ARCH CAP GROUP ORD G0450A105 5,723 17 0.30 521 -4.93 0.0704
2025-05-06 2025-03-31 13F ARCH CAP GROUP ORD G0450A105 5,706 -124 -2.13 549 1.86 0.0796
2025-01-23 2024-12-31 13F ARCH CAP GROUP ORD G0450A105 5,830 545 10.31 538 -8.97 0.0759
2024-11-07 2024-09-30 13F ARCH CAP GROUP ORD G0450A105 5,285 163 3.18 591 14.53 0.0813
2024-08-01 2024-06-30 13F ARCH CAP GROUP ORD G0450A105 5,122 -655 -11.34 517 -3.37 0.0755
2024-05-02 2024-03-31 13F ARCH CAP GROUP ORD G0450A105 5,777 643 12.52 534 40.16 0.0728
2024-02-13 2023-12-31 13F/A-1 ARCH CAP GROUP ORD G0450A105 5,134 19 0.37 381 -6.39 0.0540
2024-02-05 2023-12-31 13F ARCH CAP GROUP ORD G0450A105 5,134 19 381 0.0540
2023-11-02 2023-09-30 13F ARCH CAP GROUP ORD G0450A105 5,115 480 10.36 408 17.63 0.0643
2023-08-14 2023-06-30 13F ARCH CAP GROUP ORD G0450A105 4,635 201 4.53 347 15.33 0.0556
2023-05-05 2023-03-31 13F ARCH CAP GROUP ORD G0450A105 4,434 82 1.88 301 9.89 0.0519
2023-02-09 2022-12-31 13F ARCH CAP GROUP ORD G0450A105 4,352 131 3.10 273 15.19 0.0497
2022-11-03 2022-09-30 13F ARCH CAP GROUP ORD G0450A105 4,221 4,221 237 0.0527
2022-01-20 2021-09-30 13F/A-1 ARCH CAP GROUP ORD G0450A105 0 -6,028 -100.00 0 -100.00
2021-10-13 2021-09-30 13F ARCH CAP GROUP ORD G0450A105 0 -6,028 0
2021-07-13 2021-06-30 13F ARCH CAP GROUP ORD G0450A105 6,028 213 3.66 235 5.38 0.0423
2021-04-14 2021-03-31 13F ARCH CAP GROUP ORD G0450A105 5,815 5,815 223 0.0439
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.