Arthur J. Gallagher & Co.
MX ˙ BMV ˙ US3635761097
SecurityMX:AJG / Arthur J. Gallagher & Co.
InstitutionNissay Asset Management Corp /japan/ /adv
Latest Disclosed Ownership171,320 shares
Latest Disclosed Value $ 37,104,486
Nissay Asset Management Corp /japan/ /adv reports 64.61% increase in ownership of AJG / Arthur J. Gallagher & Co.

On May 15, 2026 - Nissay Asset Management Corp /japan/ /adv filed a 13F-HR form disclosing ownership of 171,320 shares of Arthur J. Gallagher & Co. (MX:AJG) valued at $37,104,486 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 17, 2026 disclosing 104,077 shares of Arthur J. Gallagher & Co.. This represents a change in shares of 64.61% 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)
2026-05-15 2026-03-31 13F GALLAGHER ARTHUR J COM 363576109 171,320 67,243 64.61 37,104 37.76 0.1966
2026-02-17 2025-12-31 13F GALLAGHER ARTHUR J COM 363576109 104,077 -168,450 -61.81 26,934 -68.09 0.1401
2025-11-14 2025-09-30 13F GALLAGHER ARTHUR J COM 363576109 272,527 150,111 122.62 84,413 115.41 0.4662
2025-08-14 2025-06-30 13F GALLAGHER ARTHUR J COM 363576109 122,416 -107,207 -46.69 39,188 -50.57 0.2294
2025-05-15 2025-03-31 13F GALLAGHER ARTHUR J COM 363576109 229,623 -11,361 -4.71 79,275 14.81 0.5152
2025-02-14 2024-12-31 13F GALLAGHER ARTHUR J COM 363576109 240,984 -34,495 -12.52 69,052 -10.91 0.4211
2024-11-14 2024-09-30 13F GALLAGHER ARTHUR J COM 363576109 275,479 -9,611 -3.37 77,512 4.85 0.4908
2024-08-14 2024-06-30 13F GALLAGHER ARTHUR J COM 363576109 285,090 -81,257 -22.18 73,927 -19.30 0.4894
2024-05-15 2024-03-31 13F GALLAGHER ARTHUR J COM 363576109 366,347 101,602 38.38 91,601 53.86 0.6347
2024-02-14 2023-12-31 13F GALLAGHER ARTHUR J COM 363576109 264,745 241,798 1,053.72 59,536 1,038.34 0.4788
2023-11-14 2023-09-30 13F GALLAGHER ARTHUR J COM 363576109 22,947 789 3.56 5,230 7.50 0.0464
2023-08-14 2023-06-30 13F GALLAGHER ARTHUR J COM 363576109 22,158 -73 -0.33 4,865 14.39 0.0420
2023-05-15 2023-03-31 13F GALLAGHER ARTHUR J COM 363576109 22,231 -746 -3.25 4,253 -1.82 0.0380
2023-02-14 2022-12-31 13F GALLAGHER ARTHUR J COM 363576109 22,977 -442 -1.89 4,332 8.03 0.0414
2022-11-14 2022-09-30 13F GALLAGHER ARTHUR J COM 363576109 23,419 980 4.37 4,010 9.62 0.0421
2022-08-15 2022-06-30 13F GALLAGHER ARTHUR J COM 363576109 22,439 -149 -0.66 3,658 -7.25 0.0364
2022-05-16 2022-03-31 13F GALLAGHER ARTHUR J COM 363576109 22,588 670 3.06 3,944 6.05 0.0344
2022-02-14 2021-12-31 13F GALLAGHER ARTHUR J COM 363576109 21,918 318 1.47 3,719 15.82 0.0285
2021-11-10 2021-09-30 13F GALLAGHER ARTHUR J COM 363576109 21,600 1,905 9.67 3,211 16.38 0.0272
2021-08-13 2021-06-30 13F GALLAGHER ARTHUR J COM 363576109 19,695 345 1.78 2,759 14.29 0.0242
2021-05-11 2021-03-31 13F GALLAGHER ARTHUR J COM 363576109 19,350 -368 -1.87 2,414 -1.03 0.0238
2021-02-08 2020-12-31 13F GALLAGHER ARTHUR J COM 363576109 19,718 1,147 6.18 2,439 24.38 0.0367
2020-10-20 2020-09-30 13F GALLAGHER ARTHUR J COM 363576109 18,571 522 2.89 1,961 11.42 0.0331
2020-07-27 2020-06-30 13F GALLAGHER ARTHUR J COM 363576109 18,049 400 2.27 1,760 22.31 0.0342
2020-05-05 2020-03-31 13F GALLAGHER ARTHUR J COM 363576109 17,649 469 2.73 1,439 -12.04 0.0366
2020-02-14 2019-12-31 13F GALLAGHER ARTHUR J COM 363576109 17,180 461 2.76 1,636 9.21 0.0364
2019-11-14 2019-09-30 13F GALLAGHER ARTHUR J COM 363576109 16,719 834 5.25 1,498 7.69 0.0371
2019-08-07 2019-06-30 13F GALLAGHER ARTHUR J COM 363576109 15,885 -412 -2.53 1,391 9.27 0.0352
2019-05-03 2019-03-31 13F GALLAGHER ARTHUR J COM 363576109 16,297 884 5.74 1,273 12.06 0.0336
2019-02-06 2018-12-31 13F GALLAGHER ARTHUR J COM 363576109 15,413 -28 -0.18 1,136 -1.13 0.0346
2018-10-30 2018-09-30 13F GALLAGHER ARTHUR J COM 363576109 15,441 418 2.78 1,149 17.13 0.0309
2018-08-08 2018-06-30 13F GALLAGHER ARTHUR J COM 363576109 15,023 270 1.83 981 -3.25 0.0287
2018-05-14 2018-03-31 13F GALLAGHER ARTHUR J COM 363576109 14,753 374 2.60 1,014 11.31 0.0317
2018-02-14 2017-12-31 13F GALLAGHER ARTHUR J COM 363576109 14,379 14,379 911 0.0277
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.