Arthur J. Gallagher & Co.
MX ˙ BMV ˙ US3635761097
SecurityMX:AJG / Arthur J. Gallagher & Co.
InstitutionMitchell Sinkler & Starr/pa
Latest Disclosed Ownership1,760 shares
Latest Disclosed Value $ 381,181
Mitchell Sinkler & Starr/pa ownership in AJG / Arthur J. Gallagher & Co.

On April 13, 2026 - Mitchell Sinkler & Starr/pa filed a 13F-HR form disclosing ownership of 1,760 shares of Arthur J. Gallagher & Co. (MX:AJG) valued at $381,181 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 11, 2026 disclosing 1,760 shares of Arthur J. Gallagher & Co.. This represents a change in shares of 0.00% 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)
2026-04-13 2026-03-31 13F GALLAGHER ARTHUR J COM 363576109 1,760 0 0.00 381 -16.26 0.1760
2026-02-11 2025-12-31 13F GALLAGHER ARTHUR J COM 363576109 1,760 -30 -1.68 455 -17.87 0.2058
2025-11-04 2025-09-30 13F GALLAGHER ARTHUR J COM 363576109 1,790 0 0.00 554 -3.32 0.2493
2025-07-25 2025-06-30 13F GALLAGHER ARTHUR J COM 363576109 1,790 190 11.88 573 3.80 0.2743
2025-05-07 2025-03-31 13F GALLAGHER ARTHUR J COM 363576109 1,600 -100 -5.88 552 14.52 0.1546
2025-02-12 2024-12-31 13F GALLAGHER ARTHUR J COM 363576109 1,700 0 0.00 483 0.84 0.1287
2024-11-13 2024-09-30 13F GALLAGHER ARTHUR J COM 363576109 1,700 -1,800 -51.43 478 -48.32 0.1203
2024-08-07 2024-06-30 13F GALLAGHER ARTHUR J COM 363576109 3,500 30 0.86 926 6.69 0.2376
2024-04-30 2024-03-31 13F GALLAGHER ARTHUR J COM 363576109 3,470 -30 -0.86 868 10.17 0.2170
2024-02-12 2023-12-31 13F GALLAGHER ARTHUR J COM 363576109 3,500 -50 -1.41 787 -2.72 0.1432
2023-11-01 2023-09-30 13F GALLAGHER ARTHUR J COM 363576109 3,550 0 0.00 809 3.85 0.2489
2023-07-18 2023-06-30 13F GALLAGHER ARTHUR J COM 363576109 3,550 -50 -1.39 779 13.23 0.2213
2023-05-15 2023-03-31 13F GALLAGHER ARTHUR J COM 363576109 3,600 -305 -7.81 689 -6.52 0.2036
2023-02-14 2022-12-31 13F GALLAGHER ARTHUR J COM 363576109 3,905 0 0.00 736 10.01 0.2370
2022-10-25 2022-09-30 13F GALLAGHER ARTHUR J COM 363576109 3,905 -105 -2.62 669 2.29 0.2594
2022-07-21 2022-06-30 13F GALLAGHER ARTHUR J COM 363576109 4,010 0 0.00 654 -6.57 0.2401
2022-04-19 2022-03-31 13F GALLAGHER ARTHUR J COM 363576109 4,010 0 0.00 700 2.94 0.2192
2022-02-01 2021-12-31 13F GALLAGHER ARTHUR J COM 363576109 4,010 800 24.92 680 42.56 0.2019
2021-10-12 2021-09-30 13F GALLAGHER ARTHUR J COM 363576109 3,210 0 0.00 477 6.00 0.4313
2021-07-15 2021-06-30 13F GALLAGHER ARTHUR J COM 363576109 3,210 -275 -7.89 450 3.45 0.4093
2021-04-12 2021-03-31 13F GALLAGHER ARTHUR J COM 363576109 3,485 0 0.00 435 0.93 0.4217
2021-02-09 2020-12-31 13F GALLAGHER ARTHUR J COM 363576109 3,485 310 9.76 431 28.66 0.4114
2020-10-07 2020-09-30 13F GALLAGHER ARTHUR J COM 363576109 3,175 -225 -6.62 335 1.21 0.3405
2020-07-20 2020-06-30 13F GALLAGHER ARTHUR J COM 363576109 3,400 -200 -5.56 331 12.97 0.3756
2020-04-07 2020-03-31 13F GALLAGHER ARTHUR J COM 363576109 3,600 0 0.00 293 -14.58 0.3832
2020-01-09 2019-12-31 13F GALLAGHER ARTHUR J COM 363576109 3,600 0 0.00 343 6.52 0.3644
2019-11-06 2019-09-30 13F GALLAGHER ARTHUR J COM 363576109 3,600 -2,450 -40.50 322 -39.25 0.4124
2019-07-17 2019-06-30 13F GALLAGHER ARTHUR J COM 363576109 6,050 0 0.00 530 12.05 0.6058
2019-04-08 2019-03-31 13F GALLAGHER ARTHUR J COM 363576109 6,050 -1,400 -18.79 473 -13.84 0.5462
2019-01-24 2018-12-31 13F GALLAGHER ARTHUR J COM 363576109 7,450 0 0.00 549 -1.08 0.6776
2018-10-04 2018-09-30 13F GALLAGHER ARTHUR J COM 363576109 7,450 0 0.00 555 14.20 0.5806
2018-07-11 2018-06-30 13F GALLAGHER ARTHUR J COM 363576109 7,450 -1,850 -19.89 486 -23.94 0.5357
2018-04-13 2018-03-31 13F GALLAGHER ARTHUR J COM 363576109 9,300 -1,600 -14.68 639 -7.39 0.7291
2018-01-11 2017-12-31 13F GALLAGHER ARTHUR J COM 363576109 10,900 0 0.00 690 2.83 1.0216
2017-10-23 2017-09-30 13F GALLAGHER ARTHUR J COM 363576109 10,900 0 0.00 671 7.53 1.0516
2017-07-19 2017-06-30 13F GALLAGHER ARTHUR J COM 363576109 10,900 0 0.00 624 1.30 1.0222
2017-04-19 2017-03-31 13F GALLAGHER ARTHUR J COM 363576109 10,900 0 0.00 616 8.83 1.0005
2017-01-11 2016-12-31 13F GALLAGHER ARTHUR J COM 363576109 10,900 0 0.00 566 2.17 0.7937
2016-10-11 2016-09-30 13F GALLAGHER ARTHUR J COM 363576109 10,900 0 0.00 554 6.74 0.8681
2016-07-12 2016-06-30 13F GALLAGHER ARTHUR J COMMON STOCK 363576109 10,900 -600 -5.22 519 1.37 0.7076
2016-04-15 2016-03-31 13F GALLAGHER ARTHUR J COMMON STOCK 363576109 11,500 0 0.00 512 8.70 0.7061
2016-01-11 2015-12-31 13F GALLAGHER ARTHUR J COMMON STOCK 363576109 11,500 -5,800 -33.53 471 -34.03 0.6428
2015-10-13 2015-09-30 13F GALLAGHER ARTHUR J COMMON STOCK 363576109 17,300 0 0.00 714 -12.71 0.9193
2015-07-17 2015-06-30 13F GALLAGHER ARTHUR J COMMON STOCK 363576109 17,300 0 0.00 818 1.11 0.9664
2015-04-14 2015-03-31 13F GALLAGHER ARTHUR J COMMON STOCK 363576109 17,300 17,300 0.00 809 0.9101
2015-02-03 2014-12-31 13F GALLAGHER ARTHUR J COMMON STOCK 363576109 0 -17,300 -100.00 0 -100.00
2014-10-17 2014-09-30 13F GALLAGHER ARTHUR J COMMON STOCK 363576109 17,300 0 0.00 785 -2.61 0.8769
2014-07-14 2014-06-30 13F GALLAGHER ARTHUR J COMMON STOCK 363576109 17,300 0 0.00 806 -2.07 0.8661
2014-04-09 2014-03-31 13F GALLAGHER ARTHUR J COMMON STOCK 363576109 17,300 0 0.00 823 1.35 0.9209
2014-01-23 2013-12-31 13F GALLAGHER ARTHUR J COMMON STOCK 363576109 17,300 -900 -4.95 812 2.27 0.9126
2013-10-22 2013-09-30 13F GALLAGHER ARTHUR J COMMON STOCK 363576109 18,200 8,700 91.58 794 91.33 0.9093
2013-07-24 2013-06-30 13F GALLAGHER ARTHUR J COMMON STOCK 363576109 9,500 9,500 415 0.0910
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.