Arthur J. Gallagher & Co.
MX ˙ BMV ˙ US3635761097
SecurityMX:AJG / Arthur J. Gallagher & Co.
InstitutionHighTower Advisors, LLC
Latest Disclosed Ownership47,706 shares
Latest Disclosed Value $ 10,332,684
HighTower Advisors, LLC reports 6.33% decrease in ownership of AJG / Arthur J. Gallagher & Co.

On May 5, 2026 - HighTower Advisors, LLC filed a 13F-HR form disclosing ownership of 47,706 shares of Arthur J. Gallagher & Co. (MX:AJG) valued at $10,332,684 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 6, 2026 disclosing 50,929 shares of Arthur J. Gallagher & Co.. This represents a change in shares of -6.33% 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)
2026-05-05 2026-03-31 13F GALLAGHER ARTHUR J COM 363576109 47,706 -3,223 -6.33 10,333 -21.60 0.0110
2026-02-06 2025-12-31 13F GALLAGHER ARTHUR J COM 363576109 50,929 -15,411 -23.23 13,180 -35.92 0.0144
2025-11-07 2025-09-30 13F GALLAGHER ARTHUR J COM 363576109 66,340 8,401 14.50 20,567 10.89 0.0234
2025-08-11 2025-06-30 13F GALLAGHER ARTHUR J COM 363576109 57,939 556 0.97 18,547 -6.38 0.0232
2025-05-13 2025-03-31 13F GALLAGHER ARTHUR J COM 363576109 57,383 531 0.93 19,811 22.76 0.0269
2025-02-07 2024-12-31 13F GALLAGHER ARTHUR J COM 363576109 56,852 180 0.32 16,138 0.98 0.0221
2024-11-14 2024-09-30 13F GALLAGHER ARTHUR J COM 363576109 56,672 789 1.41 15,980 10.04 0.0228
2024-08-13 2024-06-30 13F GALLAGHER ARTHUR J COM 363576109 55,883 1,500 2.76 14,522 5.61 0.0225
2024-05-06 2024-03-31 13F GALLAGHER ARTHUR J COM 363576109 54,383 -1,675 -2.99 13,750 9.39 0.0223
2024-02-12 2023-12-31 13F GALLAGHER ARTHUR J COM 363576109 56,058 -1,725 -2.99 12,570 -4.57 0.0211
2023-11-08 2023-09-30 13F GALLAGHER ARTHUR J COM 363576109 57,783 20,690 55.78 13,172 61.70 0.0247
2023-08-14 2023-06-30 13F GALLAGHER ARTHUR J COM 363576109 37,093 -55,522 -59.95 8,146 -54.05 0.0160
2023-05-12 2023-03-31 13F GALLAGHER ARTHUR J COM 363576109 92,615 -214 -0.23 17,727 1.22 0.0387
2023-02-09 2022-12-31 13F GALLAGHER ARTHUR J COM 363576109 92,829 -822 -0.88 17,513 9.21 0.0400
2022-11-09 2022-09-30 13F GALLAGHER ARTHUR J COM 363576109 93,651 297 0.32 16,036 5.34 0.0430
2022-08-10 2022-06-30 13F GALLAGHER ARTHUR J COM 363576109 93,354 -234 -0.25 15,223 -6.76 0.0393
2022-05-12 2022-03-31 13F GALLAGHER ARTHUR J COM 363576109 93,588 984 1.06 16,326 3.88 0.0364
2022-02-10 2021-12-31 13F GALLAGHER ARTHUR J COM 363576109 92,604 -887 -0.95 15,716 13.15 0.0344
2021-11-12 2021-09-30 13F GALLAGHER ARTHUR J COM 363576109 93,491 57,227 157.81 13,890 173.32 0.0372
2021-08-06 2021-06-30 13F GALLAGHER ARTHUR J COM 363576109 36,264 855 2.41 5,082 15.45 0.0147
2021-05-10 2021-03-31 13F GALLAGHER ARTHUR J COM 363576109 35,409 3,982 12.67 4,402 13.40 0.0139
2021-02-10 2020-12-31 13F GALLAGHER ARTHUR J COM 363576109 31,427 5,816 22.71 3,882 43.57 0.0162
2020-11-13 2020-09-30 13F GALLAGHER ARTHUR J COM 363576109 25,611 12,944 102.19 2,704 118.77 0.0131
2020-08-10 2020-06-30 13F GALLAGHER ARTHUR J COM 363576109 12,667 -8,802 -41.00 1,236 -29.25 0.0067
2020-05-21 2020-03-31 13F GALLAGHER ARTHUR J COM 363576109 21,469 -2,338 -9.82 1,747 -22.94 0.0113
2020-02-14 2019-12-31 13F GALLAGHER ARTHUR J COM 363576109 23,807 -307 -1.27 2,267 4.91 0.0134
2019-11-12 2019-09-30 13F GALLAGHER ARTHUR J COM 363576109 24,114 -438 -1.78 2,161 0.32 0.0118
2019-08-13 2019-06-30 13F GALLAGHER ARTHUR J COM 363576109 24,552 1,627 7.10 2,154 20.47 0.0128
2019-05-15 2019-03-31 13F GALLAGHER ARTHUR J COM 363576109 22,925 2,056 9.85 1,788 16.18 0.0119
2019-02-14 2018-12-31 13F GALLAGHER ARTHUR J COM 363576109 20,869 12,287 143.17 1,539 142.36 0.0118
2018-11-09 2018-09-30 13F GALLAGHER ARTHUR J COM 363576109 8,582 -1,233 -12.56 635 -0.94 0.0046
2018-08-14 2018-06-30 13F GALLAGHER ARTHUR J COM 363576109 9,815 -4,308 -30.50 641 -33.99 0.0050
2018-05-15 2018-03-31 13F GALLAGHER ARTHUR J COM 363576109 14,123 583 4.31 971 13.17 0.0081
2018-02-14 2017-12-31 13F GALLAGHER ARTHUR J COM 363576109 13,540 -2,710 -16.68 858 -14.20 0.0070
2017-11-14 2017-09-30 13F GALLAGHER ARTHUR J COM 363576109 16,250 -8,699 -34.87 1,000 -30.07 0.0085
2017-09-22 2017-06-30 13F/A-1 GALLAGHER ARTHUR J COM 363576109 24,949 763 3.15 1,430 4.46 0.0128
2017-08-14 2017-06-30 13F GALLAGHER ARTHUR J COM 363576109 24,949 763 1,430
2017-05-15 2017-03-31 13F GALLAGHER ARTHUR J COM 363576109 24,186 1,087 4.71 1,369 13.89 0.0131
2017-02-10 2016-12-31 13F GALLAGHER ARTHUR J COM 363576109 23,099 23,099 0.00 1,202 0.0131
2016-08-11 2016-06-30 13F GALLAGHER ARTHUR J COM 363576109 0 -20,249 -100.00 0 -100.00
2016-05-16 2016-03-31 13F GALLAGHER ARTHUR J COM 363576109 20,249 -2,680 -11.69 894 -4.99 0.0029
2016-05-18 2015-12-31 13F/A-1 GALLAGHER ARTHUR J COM 363576109 22,929 8,352 57.30 941 55.28 0.0112
2016-02-12 2015-12-31 13F GALLAGHER ARTHUR J COM 363576109 22,929 941
2015-11-16 2015-09-30 13F GALLAGHER ARTHUR J COM 363576109 14,577 -1,239 -7.83 606 -18.98 0.0080
2015-08-11 2015-06-30 13F GALLAGHER ARTHUR J COM 363576109 15,816 15,816 748 0.0120
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.