Arthur J. Gallagher & Co.
US ˙ NYSE ˙ US3635761097

SecurityAJG / Arthur J. Gallagher & Co.
InstitutionDynamic Technology Lab Private Ltd
Latest Disclosed Ownership2,004 shares
Latest Disclosed Value $ 434,026
Dynamic Technology Lab Private Ltd ownership in AJG / Arthur J. Gallagher & Co.

On May 15, 2026 - Dynamic Technology Lab Private Ltd filed a 13F-HR form disclosing ownership of 2,004 shares of Arthur J. Gallagher & Co. (US:AJG) valued at $434,026 USD as of March 31, 2026. The entity filed a previous 13F-HR on November 13, 2025 disclosing 0 shares of Arthur J. Gallagher & Co.. The current value of the position is $405,810 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)
2026-05-15 2026-03-31 13F GALLAGHER ARTHUR J COM 363576109 2,004 2,004 434 0.0705
2025-11-13 2025-09-30 13F GALLAGHER ARTHUR J COM 363576109 0 -3,822 -100.00 0 -100.00
2025-08-12 2025-06-30 13F GALLAGHER ARTHUR J COM 363576109 3,822 3,822 1,223 0.1662
2025-02-13 2024-12-31 13F GALLAGHER ARTHUR J COM 363576109 0 -11,361 -100.00 0 -100.00
2024-11-13 2024-09-30 13F GALLAGHER ARTHUR J COM 363576109 11,361 11,361 3,196 0.3383
2024-08-15 2024-06-30 13F GALLAGHER ARTHUR J COM 363576109 0 -5,566 -100.00 0 -100.00
2024-05-14 2024-03-31 13F GALLAGHER ARTHUR J COM 363576109 5,566 4,390 373.30 1 0.1487
2024-02-09 2023-12-31 13F GALLAGHER ARTHUR J COM 363576109 1,176 1,176 0 0.0279
2023-11-14 2023-09-30 13F GALLAGHER ARTHUR J COM 363576109 0 -5,844 -100.00 0 -100.00
2023-08-14 2023-06-30 13F GALLAGHER ARTHUR J COM 363576109 5,844 5,844 1 0.1618
2022-11-14 2022-09-30 13F GALLAGHER ARTHUR J COM 363576109 0 -2,443 -100.00 0 -100.00
2022-08-12 2022-06-30 13F GALLAGHER ARTHUR J COM 363576109 2,443 2,443 398 0.0450
2022-05-16 2022-03-31 13F GALLAGHER ARTHUR J COM 363576109 0 -6,873 -100.00 0 -100.00
2022-02-14 2021-12-31 13F GALLAGHER ARTHUR J COM 363576109 6,873 6,873 1,166 0.1291
2021-11-15 2021-09-30 13F GALLAGHER ARTHUR J COM 363576109 0 -15,174 -100.00 0 -100.00
2021-08-13 2021-06-30 13F GALLAGHER ARTHUR J COM 363576109 15,174 15,174 2,126 0.2138
2020-05-13 2020-03-31 13F GALLAGHER ARTHUR J COM 363576109 0 -9,126 -100.00 0 -100.00
2020-02-14 2019-12-31 13F GALLAGHER ARTHUR J COM 363576109 9,126 4,622 102.62 869 115.63 0.1393
2019-11-14 2019-09-30 13F GALLAGHER ARTHUR J COM 363576109 4,504 -13,805 -75.40 403 -74.88 0.0708
2019-08-14 2019-06-30 13F GALLAGHER ARTHUR J COM 363576109 18,309 -21,721 -54.26 1,604 -48.69 0.2700
2019-05-13 2019-03-31 13F GALLAGHER ARTHUR J COM 363576109 40,030 40,030 118.64 3,126 94.89 0.5124
2018-11-14 2018-09-30 13F GALLAGHER ARTHUR J COM 363576109 0 -27,844 -100.00 0 -100.00
2018-08-14 2018-06-30 13F GALLAGHER ARTHUR J COM 363576109 27,844 16,379 142.86 1,818 130.71 0.2737
2018-06-14 2018-03-31 13F/A-1 GALLAGHER ARTHUR J COM 363576109 11,465 4,038 54.37 788 67.66 0.1173
2018-05-14 2018-03-31 13F GALLAGHER ARTHUR J COM 363576109 11,465 4,038 788
2018-02-09 2017-12-31 13F GALLAGHER ARTHUR J COM 363576109 7,427 1,883 33.96 470 38.24 0.0834
2017-11-08 2017-09-30 13F GALLAGHER ARTHUR J COM 363576109 5,544 -4,598 -45.34 340 -41.48 0.0552
2017-08-17 2017-06-30 13F GALLAGHER ARTHUR J COM 363576109 10,142 10,142 581 0.1097
2016-11-14 2016-09-30 13F GALLAGHER ARTHUR J COM 363576109 0 -8,793 -100.00 0 -100.00
2016-08-10 2016-06-30 13F GALLAGHER ARTHUR J COM 363576109 8,793 8,793 0.00 418 0.1131
2015-08-13 2015-06-30 13F GALLAGHER ARTHUR J COM 363576109 0 -7,048 -100.00 0 -100.00
2016-03-01 2015-03-31 13F/A-1 GALLAGHER ARTHUR J COM 363576109 7,048 251 3.69 329 3.13 0.3077
2016-02-22 2013-12-31 13F/A-1 GALLAGHER ARTHUR J COM 363576109 6,797 -2,121 -23.78 319 -17.99 0.5278
2016-02-22 2013-09-30 13F/A-1 GALLAGHER ARTHUR J COM 363576109 8,918 8,918 389 0.6671
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.