Arthur J. Gallagher & Co.
MX ˙ BMV ˙ US3635761097
SecurityMX:AJG / Arthur J. Gallagher & Co.
InstitutionBallentine Partners, LLC
Latest Disclosed Ownership3,507 shares
Latest Disclosed Value $ 759,547
Ballentine Partners, LLC reports 118.78% increase in ownership of AJG / Arthur J. Gallagher & Co.

On May 14, 2026 - Ballentine Partners, LLC filed a 13F-HR form disclosing ownership of 3,507 shares of Arthur J. Gallagher & Co. (MX:AJG) valued at $759,547 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 3, 2026 disclosing 1,603 shares of Arthur J. Gallagher & Co.. This represents a change in shares of 118.78% 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)
2026-05-14 2026-03-31 13F GALLAGHER ARTHUR J COM 363576109 3,507 1,904 118.78 760 83.33 0.0106
2026-02-03 2025-12-31 13F GALLAGHER ARTHUR J COM 363576109 1,603 -613 -27.66 415 -39.65 0.0058
2025-11-03 2025-09-30 13F GALLAGHER ARTHUR J COM 363576109 2,216 456 25.91 686 21.85 0.0095
2025-07-15 2025-06-30 13F GALLAGHER ARTHUR J COM 363576109 1,760 150 9.32 563 1.44 0.0085
2025-05-01 2025-03-31 13F GALLAGHER ARTHUR J COM 363576109 1,610 396 32.62 556 61.34 0.0096
2025-01-16 2024-12-31 13F GALLAGHER ARTHUR J COM 363576109 1,214 49 4.21 345 5.20 0.0059
2024-10-23 2024-09-30 13F GALLAGHER ARTHUR J COM 363576109 1,165 78 7.18 328 16.37 0.0056
2024-08-06 2024-06-30 13F GALLAGHER ARTHUR J COM 363576109 1,087 218 25.09 282 29.49 0.0052
2024-04-11 2024-03-31 13F GALLAGHER ARTHUR J COM 363576109 869 869 217 0.0041
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.