Arthur J. Gallagher & Co.
MX ˙ BMV ˙ US3635761097
SecurityMX:AJG / Arthur J. Gallagher & Co.
InstitutionEventide Asset Management, Llc
Latest Disclosed Ownership83,670 shares
Latest Disclosed Value $ 18,113,292
Eventide Asset Management, Llc reports 40.18% decrease in ownership of AJG / Arthur J. Gallagher & Co.

On May 15, 2026 - Eventide Asset Management, Llc filed a 13F-HR form disclosing ownership of 83,670 shares of Arthur J. Gallagher & Co. (MX:AJG) valued at $18,113,292 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 13, 2026 disclosing 139,874 shares of Arthur J. Gallagher & Co.. This represents a change in shares of -40.18% 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 83,670 -56,204 -40.18 18,113 -50.02 0.2996
2026-02-13 2025-12-31 13F GALLAGHER ARTHUR J COM 363576109 139,874 -76,819 -35.45 36,244 -45.95 0.5662
2025-11-14 2025-09-30 13F GALLAGHER ARTHUR J COM 363576109 216,693 6,122 2.91 67,058 -0.48 1.1025
2025-08-14 2025-06-30 13F GALLAGHER ARTHUR J COM 363576109 210,571 1,422 0.68 67,384 -6.64 1.1806
2025-05-15 2025-03-31 13F GALLAGHER ARTHUR J COM 363576109 209,149 11,199 5.66 72,178 28.45 1.4378
2025-02-14 2024-12-31 13F GALLAGHER ARTHUR J COM 363576109 197,950 5,746 2.99 56,191 3.90 1.0232
2024-11-14 2024-09-30 13F GALLAGHER ARTHUR J COM 363576109 192,204 -6,491 -3.27 54,080 4.96 0.9321
2024-08-13 2024-06-30 13F GALLAGHER ARTHUR J COM 363576109 198,695 42,535 27.24 51,524 31.95 0.8820
2024-05-15 2024-03-31 13F GALLAGHER ARTHUR J COM 363576109 156,160 29,974 23.75 39,046 37.60 0.6123
2024-02-20 2023-12-31 13F/A-1 GALLAGHER ARTHUR J COM 363576109 126,186 17,627 16.24 28,377 14.68 0.4632
2024-02-14 2023-12-31 13F GALLAGHER ARTHUR J COM 363576109 126,186 17,627 28,377 0.4631
2023-11-14 2023-09-30 13F GALLAGHER ARTHUR J COM 363576109 108,559 10,960 11.23 24,744 15.47 0.4447
2023-08-15 2023-06-30 13F GALLAGHER ARTHUR J COM 363576109 97,599 -22,159 -18.50 21,430 -6.46 0.3622
2023-05-15 2023-03-31 13F GALLAGHER ARTHUR J COM 363576109 119,758 27,676 30.06 22,911 31.96 0.4203
2023-02-13 2022-12-31 13F GALLAGHER ARTHUR J COM 363576109 92,082 58,150 171.37 17,361 198.81 0.3423
2022-11-14 2022-09-30 13F GALLAGHER ARTHUR J COM 363576109 33,932 33,932 5,810 0.1143
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.