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

SecurityAJG / Arthur J. Gallagher & Co.
InstitutionAviva Plc
Latest Disclosed Ownership211,415 shares
Latest Disclosed Value $ 45,788,261
Aviva Plc reports 2.96% increase in ownership of AJG / Arthur J. Gallagher & Co.

On May 14, 2026 - Aviva Plc filed a 13F-HR form disclosing ownership of 211,415 shares of Arthur J. Gallagher & Co. (US:AJG) valued at $45,788,261 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 12, 2026 disclosing 205,332 shares of Arthur J. Gallagher & Co.. This represents a change in shares of 2.96% during the quarter. The current value of the position is $44,608,565 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)
2026-05-14 2026-03-31 13F GALLAGHER ARTHUR J COM 363576109 211,415 6,083 2.96 45,788 -13.83 0.0768
2026-02-12 2025-12-31 13F GALLAGHER ARTHUR J COM 363576109 205,332 7,276 3.67 53,138 -13.38 0.0896
2025-11-13 2025-09-30 13F GALLAGHER ARTHUR J COM 363576109 198,056 -64,944 -24.69 61,346 -27.14 0.1115
2025-08-07 2025-06-30 13F GALLAGHER ARTHUR J COM 363576109 263,000 -141,061 -34.91 84,192 -39.65 0.1739
2025-05-15 2025-03-31 13F GALLAGHER ARTHUR J COM 363576109 404,061 12,845 3.28 139,498 25.62 0.3366
2025-02-13 2024-12-31 13F GALLAGHER ARTHUR J COM 363576109 391,216 37,196 10.51 111,047 11.48 0.2884
2024-11-14 2024-09-30 13F GALLAGHER ARTHUR J COM 363576109 354,020 25,331 7.71 99,611 16.87 0.2581
2024-08-02 2024-06-30 13F GALLAGHER ARTHUR J COM 363576109 328,689 -3,786 -1.14 85,232 2.53 0.2363
2024-05-14 2024-03-31 13F GALLAGHER ARTHUR J COM 363576109 332,475 -25,423 -7.10 83,132 3.29 0.2737
2024-02-09 2023-12-31 13F GALLAGHER ARTHUR J COM 363576109 357,898 97,225 37.30 80,484 35.46 0.2885
2023-11-13 2023-09-30 13F GALLAGHER ARTHUR J COM 363576109 260,673 211,716 432.45 59,415 452.75 0.2499
2023-08-10 2023-06-30 13F GALLAGHER ARTHUR J COM 363576109 48,957 30,593 166.59 10,749 205.98 0.0438
2023-05-12 2023-03-31 13F GALLAGHER ARTHUR J COM 363576109 18,364 -15,716 -46.12 3,513 -45.32 0.0159
2023-02-14 2022-12-31 13F/A-2 GALLAGHER ARTHUR J COM 363576109 34,080 -14,408 -29.71 6,425 -22.61 0.0316
2023-02-10 2022-12-31 13F/A-1 GALLAGHER ARTHUR J COM 363576109 34,080 -14,408 1,070 0.0051
2023-02-09 2022-12-31 13F GALLAGHER ARTHUR J COM 363576109 34,080 -14,408 6 0.0309
2022-11-14 2022-09-30 13F GALLAGHER ARTHUR J COM 363576109 48,488 15,542 47.17 8,302 54.54 0.0478
2022-08-04 2022-06-30 13F GALLAGHER ARTHUR J COM 363576109 32,946 -26,952 -45.00 5,372 -48.63 0.0286
2022-05-13 2022-03-31 13F GALLAGHER ARTHUR J COM 363576109 59,898 -279,074 -82.33 10,458 -81.82 0.0523
2022-02-10 2021-12-31 13F GALLAGHER ARTHUR J COM 363576109 338,972 -7,612 -2.20 57,513 11.63 0.2411
2021-11-12 2021-09-30 13F GALLAGHER ARTHUR J COM 363576109 346,584 -18,046 -4.95 51,519 0.87 0.2298
2021-08-10 2021-06-30 13F GALLAGHER ARTHUR J COM 363576109 364,630 3,028 0.84 51,077 13.21 0.2240
2021-05-13 2021-03-31 13F GALLAGHER ARTHUR J COM 363576109 361,602 -145,323 -28.67 45,117 -28.06 0.2204
2021-02-10 2020-12-31 13F GALLAGHER ARTHUR J COM 363576109 506,925 -4,997 -0.98 62,712 16.03 0.3262
2020-11-12 2020-09-30 13F GALLAGHER ARTHUR J COM 363576109 511,922 61,661 13.69 54,048 23.13 0.3188
2020-08-13 2020-06-30 13F/A-1 GALLAGHER ARTHUR J COM 363576109 450,261 -53,344 -10.59 43,896 6.94 0.2736
2020-08-13 2020-06-30 13F GALLAGHER ARTHUR J COM 363576109 450,261 -53,344 43,896 132,892.0190
2020-05-14 2020-03-31 13F GALLAGHER ARTHUR J COM 363576109 503,605 217,814 76.21 41,049 50.83 0.3007
2020-02-10 2019-12-31 13F GALLAGHER ARTHUR J COM 363576109 285,791 197,927 225.27 27,216 245.82 0.1648
2019-11-12 2019-09-30 13F GALLAGHER ARTHUR J COM 363576109 87,864 1,248 1.44 7,870 3.73 0.0533
2019-07-30 2019-06-30 13F GALLAGHER ARTHUR J COM 363576109 86,616 18,417 27.00 7,587 42.45 0.0521
2019-05-14 2019-03-31 13F GALLAGHER ARTHUR J COM 363576109 68,199 208 0.31 5,326 6.29 0.0357
2019-02-12 2018-12-31 13F GALLAGHER ARTHUR J COM 363576109 67,991 -19,426 -22.22 5,011 -22.99 0.0374
2018-11-13 2018-09-30 13F GALLAGHER ARTHUR J COM 363576109 87,417 -2,887 -3.20 6,507 10.38 0.0357
2018-08-01 2018-06-30 13F GALLAGHER ARTHUR J COM 363576109 90,304 -547 -0.60 5,895 -5.59 0.0348
2018-05-14 2018-03-31 13F GALLAGHER ARTHUR J COM 363576109 90,851 -7,473 -7.60 6,244 0.35 0.0382
2018-02-13 2017-12-31 13F GALLAGHER ARTHUR J COM 363576109 98,324 -13,518 -12.09 6,222 -9.63 0.0352
2017-11-13 2017-09-30 13F GALLAGHER ARTHUR J COM 363576109 111,842 820 0.74 6,885 8.32 0.0371
2017-08-07 2017-06-30 13F GALLAGHER ARTHUR J COM 363576109 111,022 990 0.90 6,356 2.15 0.0355
2017-05-15 2017-03-31 13F GALLAGHER ARTHUR J COM 363576109 110,032 -3,574 -3.15 6,222 5.39 0.0356
2017-02-13 2016-12-31 13F GALLAGHER ARTHUR J COM 363576109 113,606 6,123 5.70 5,904 7.97 0.0353
2016-11-14 2016-09-30 13F GALLAGHER ARTHUR J COM 363576109 107,483 3,223 3.09 5,468 10.15 0.0341
2016-08-05 2016-06-30 13F GALLAGHER ARTHUR J COM 363576109 104,260 15,735 17.77 4,964 26.05 0.0340
2016-05-12 2016-03-31 13F GALLAGHER ARTHUR J COM 363576109 88,525 1,213 1.39 3,938 10.15 0.0293
2016-02-11 2015-12-31 13F GALLAGHER ARTHUR J COM 363576109 87,312 1,993 2.34 3,575 1.50 0.0271
2015-11-12 2015-09-30 13F GALLAGHER ARTHUR J COM 363576109 85,319 -608 -0.71 3,522 -13.34 0.0292
2015-08-06 2015-06-30 13F GALLAGHER ARTHUR J COM 363576109 85,927 -630 -0.73 4,064 0.42 0.0288
2015-05-14 2015-03-31 13F GALLAGHER ARTHUR J COM 363576109 86,557 86,557 0.00 4,047 0.0277
2015-02-05 2014-12-31 13F/A-1 GALLAGHER ARTHUR J COM 363576109 0 -61,790 -100.00 0 -100.00
2014-11-13 2014-09-30 13F GALLAGHER ARTHUR J COM 363576109 61,790 260 0.42 2,803 -2.23 0.0222
2014-08-13 2014-06-30 13F GALLAGHER ARTHUR J COM 363576109 61,530 7,250 13.36 2,867 10.99 0.0219
2014-05-14 2014-03-31 13F GALLAGHER ARTHUR J COM 363576109 54,280 6,090 12.64 2,583 14.19 0.0209
2014-02-13 2013-12-31 13F GALLAGHER ARTHUR J COM 363576109 48,190 2,110 4.58 2,262 12.48 0.0189
2013-11-13 2013-09-30 13F GALLAGHER ARTHUR J COM 363576109 46,080 13,319 40.66 2,011 40.53 0.0176
2013-08-01 2013-06-30 13F GALLAGHER ARTHUR J COM 363576109 32,761 32,761 1,431 0.0145
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.