Arthur J. Gallagher & Co.
MX ˙ BMV ˙ US3635761097
SecurityMX:AJG / Arthur J. Gallagher & Co.
InstitutionProspera Financial Services Inc
Latest Disclosed Ownership23,928 shares
Latest Disclosed Value $ 5,182,135
Prospera Financial Services Inc reports 0.66% increase in ownership of AJG / Arthur J. Gallagher & Co.

On April 14, 2026 - Prospera Financial Services Inc filed a 13F-HR form disclosing ownership of 23,928 shares of Arthur J. Gallagher & Co. (MX:AJG) valued at $5,182,135 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 9, 2026 disclosing 23,772 shares of Arthur J. Gallagher & Co.. This represents a change in shares of 0.66% during the quarter.

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)
2026-04-14 2026-03-31 13F GALLAGHER ARTHUR J COM 363576109 23,928 156 0.66 5,182 -15.75 0.0835
2026-02-09 2025-12-31 13F GALLAGHER ARTHUR J COM 363576109 23,772 209 0.89 6,152 -15.72 0.1010
2025-11-06 2025-09-30 13F GALLAGHER ARTHUR J COM 363576109 23,563 553 2.40 7,299 -0.92 0.1245
2025-08-06 2025-06-30 13F GALLAGHER ARTHUR J COM 363576109 23,010 607 2.71 7,366 -4.76 0.1372
2025-05-15 2025-03-31 13F GALLAGHER ARTHUR J COM 363576109 22,403 780 3.61 7,735 26.02 0.1777
2025-02-13 2024-12-31 13F GALLAGHER ARTHUR J COM 363576109 21,623 6,434 42.36 6,138 43.62 0.1430
2024-11-07 2024-09-30 13F GALLAGHER ARTHUR J COM 363576109 15,189 2,110 16.13 4,274 26.01 0.1091
2024-08-13 2024-06-30 13F GALLAGHER ARTHUR J COM 363576109 13,079 1,160 9.73 3,391 13.79 0.0943
2024-08-13 2024-03-31 13F GALLAGHER ARTHUR J COM 363576109 11,919 716 6.39 2,980 18.30 0.0888
2024-02-14 2023-12-31 13F GALLAGHER ARTHUR J COM 363576109 11,203 -1,247 -10.02 2,519 -11.21 0.0834
2023-11-13 2023-09-30 13F GALLAGHER ARTHUR J COM 363576109 12,450 1,068 9.38 2,838 13.53 0.1097
2023-08-08 2023-06-30 13F GALLAGHER ARTHUR J COM 363576109 11,382 435 3.97 2,499 19.34 0.0956
2023-05-12 2023-03-31 13F GALLAGHER ARTHUR J COM 363576109 10,947 891 8.86 2,094 10.44 0.0861
2023-02-08 2022-12-31 13F GALLAGHER ARTHUR J COM 363576109 10,056 760 8.18 1,896 19.10 0.0950
2022-10-27 2022-09-30 13F GALLAGHER ARTHUR J COM 363576109 9,296 -1,005 -9.76 1,592 -5.18 0.0831
2022-08-08 2022-06-30 13F GALLAGHER ARTHUR J COM 363576109 10,301 431 4.37 1,679 -2.55 0.0856
2022-05-04 2022-03-31 13F GALLAGHER ARTHUR J COM 363576109 9,870 556 5.97 1,723 9.05 0.0721
2022-02-10 2021-12-31 13F GALLAGHER ARTHUR J COM 363576109 9,314 -206 -2.16 1,580 11.66 0.0683
2021-11-12 2021-09-30 13F GALLAGHER ARTHUR J COM 363576109 9,520 171 1.83 1,415 8.10 0.0705
2021-08-16 2021-06-30 13F/A-1 GALLAGHER ARTHUR J COM 363576109 9,349 -116 -1.23 1,309 10.84 0.0656
2021-08-12 2021-06-30 13F GALLAGHER ARTHUR J COM 363576109 9,349 -116 1,310 0.0674
2021-05-06 2021-03-31 13F GALLAGHER ARTHUR J COM 363576109 9,465 1,358 16.75 1,181 17.86 0.0701
2021-02-12 2020-12-31 13F GALLAGHER ARTHUR J COM 363576109 8,107 7,953 5,164.29 1,002 6,162.50 0.0690
2020-11-04 2020-09-30 13F GALLAGHER ARTHUR J COM 363576109 154 -9,112 -98.34 16 -98.23 0.0061
2020-08-10 2020-06-30 13F GALLAGHER ARTHUR J COM 363576109 9,266 1,499 19.30 903 42.65 0.0800
2020-05-15 2020-03-31 13F GALLAGHER ARTHUR J COM 363576109 7,767 -430 -5.25 633 -18.95 0.0672
2020-02-12 2019-12-31 13F GALLAGHER ARTHUR J COM 363576109 8,197 2,336 39.86 781 48.76 0.0602
2019-10-22 2019-09-30 13F GALLAGHER ARTHUR J COM 363576109 5,861 450 8.32 525 7.14 0.0539
2019-08-14 2019-06-30 13F/A-1 GALLAGHER ARTHUR J COM 363576109 5,411 1,758 48.12 490 71.93 0.0550
2019-05-02 2019-03-31 13F GALLAGHER ARTHUR J COM 363576109 3,653 3,653 285 0.0938
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.