Arthur J. Gallagher & Co.
MX ˙ BMV ˙ US3635761097
SecurityMX:AJG / Arthur J. Gallagher & Co.
InstitutionWelch & Forbes Llc
Latest Disclosed Ownership293,288 shares
Latest Disclosed Value $ 63,520,469
Welch & Forbes Llc reports 0.34% decrease in ownership of AJG / Arthur J. Gallagher & Co.

On May 1, 2026 - Welch & Forbes Llc filed a 13F-HR form disclosing ownership of 293,288 shares of Arthur J. Gallagher & Co. (MX:AJG) valued at $63,520,469 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 10, 2026 disclosing 294,278 shares of Arthur J. Gallagher & Co.. This represents a change in shares of -0.34% 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)
2026-05-01 2026-03-31 13F GALLAGHER ARTHUR J COM 363576109 293,288 -990 -0.34 63,520 -16.59 0.8212
2026-02-10 2025-12-31 13F GALLAGHER ARTHUR J COM 363576109 294,278 1,508 0.52 76,156 -16.02 0.9226
2025-11-04 2025-09-30 13F GALLAGHER ARTHUR J COM 363576109 292,770 -1,821 -0.62 90,683 -3.84 1.0921
2025-08-05 2025-06-30 13F GALLAGHER ARTHUR J COM 363576109 294,591 -3,295 -1.11 94,305 -8.30 1.1776
2025-05-02 2025-03-31 13F GALLAGHER ARTHUR J COM 363576109 297,886 -2,255 -0.75 102,842 20.71 1.3455
2025-02-07 2024-12-31 13F GALLAGHER ARTHUR J COM 363576109 300,141 -2,617 -0.86 85,195 0.01 1.0953
2024-11-04 2024-09-30 13F GALLAGHER ARTHUR J COM 363576109 302,758 -2,994 -0.98 85,187 5.84 1.0841
2024-08-02 2024-06-30 13F GALLAGHER ARTHUR J COM 363576109 305,752 -4,669 -1.50 80,491 3.70 1.0741
2024-05-03 2024-03-31 13F GALLAGHER ARTHUR J COM 363576109 310,421 9,293 3.09 77,618 14.62 1.0655
2024-02-06 2023-12-31 13F GALLAGHER ARTHUR J COM 363576109 301,128 6,478 2.20 67,718 0.83 1.0229
2023-11-03 2023-09-30 13F GALLAGHER ARTHUR J COM 363576109 294,650 -2,064 -0.70 67,160 3.09 1.1104
2023-07-28 2023-06-30 13F GALLAGHER ARTHUR J COM 363576109 296,714 -2,641 -0.88 65,150 13.76 1.0277
2023-04-14 2023-03-31 13F GALLAGHER ARTHUR J COM 363576109 299,355 5,247 1.78 57,270 3.28 0.9698
2023-02-02 2022-12-31 13F GALLAGHER ARTHUR J COM 363576109 294,108 -3,022 -1.02 55,451 9.00 0.9939
2022-10-31 2022-09-30 13F GALLAGHER ARTHUR J COM 363576109 297,130 890 0.30 50,874 5.33 0.9935
2022-07-22 2022-06-30 13F GALLAGHER ARTHUR J COM 363576109 296,240 1,777 0.60 48,300 -6.05 0.8837
2022-04-25 2022-03-31 13F GALLAGHER ARTHUR J COM 363576109 294,463 8,368 2.92 51,413 5.91 0.8100
2022-01-19 2021-12-31 13F GALLAGHER ARTHUR J COM 363576109 286,095 -596 -0.21 48,542 13.90 0.7267
2021-10-13 2021-09-30 13F GALLAGHER ARTHUR J COM 363576109 286,691 5,601 1.99 42,617 8.23 0.7082
2021-07-22 2021-06-30 13F GALLAGHER ARTHUR J COM 363576109 281,090 28,845 11.44 39,375 25.11 0.6653
2021-04-14 2021-03-31 13F GALLAGHER ARTHUR J COM 363576109 252,245 5,459 2.21 31,473 3.09 0.5812
2021-01-20 2020-12-31 13F GALLAGHER ARTHUR J COM 363576109 246,786 18,256 7.99 30,531 26.54 0.5973
2020-10-23 2020-09-30 13F GALLAGHER ARTHUR J COM 363576109 228,530 29,508 14.83 24,128 24.35 0.5207
2020-07-15 2020-06-30 13F GALLAGHER ARTHUR J COM 363576109 199,022 36,584 22.52 19,403 46.56 0.4545
2020-04-17 2020-03-31 13F GALLAGHER ARTHUR J COM 363576109 162,438 38,500 31.06 13,239 12.18 0.3698
2020-01-17 2019-12-31 13F GALLAGHER ARTHUR J COM 363576109 123,938 33,464 36.99 11,802 45.63 0.2626
2019-10-11 2019-09-30 13F GALLAGHER ARTHUR J COM 363576109 90,474 13,565 17.64 8,104 20.29 0.1934
2019-07-12 2019-06-30 13F GALLAGHER ARTHUR J COM 363576109 76,909 62,646 439.22 6,737 504.76 0.1640
2019-04-29 2019-03-31 13F GALLAGHER ARTHUR J COM 363576109 14,263 11,213 367.64 1,114 395.11 0.0279
2019-02-05 2018-12-31 13F GALLAGHER ARTHUR J COM 363576109 3,050 3,050 225 0.0063
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.