Arthur J. Gallagher & Co.
MX ˙ BMV ˙ US3635761097
SecurityMX:AJG / Arthur J. Gallagher & Co.
InstitutionDuncker Streett & Co Inc
Latest Disclosed Ownership103 shares
Latest Disclosed Value $ 22,308
Duncker Streett & Co Inc reports 99.17% decrease in ownership of AJG / Arthur J. Gallagher & Co.

On April 29, 2026 - Duncker Streett & Co Inc filed a 13F-HR form disclosing ownership of 103 shares of Arthur J. Gallagher & Co. (MX:AJG) valued at $22,308 USD as of March 31, 2026. The entity filed a previous 13F-HR on January 27, 2026 disclosing 12,448 shares of Arthur J. Gallagher & Co.. This represents a change in shares of -99.17% 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)
2026-04-29 2026-03-31 13F GALLAGHER ARTHUR J COM 363576109 103 -12,345 -99.17 22 -99.32 0.0042
2026-01-27 2025-12-31 13F GALLAGHER ARTHUR J COM 363576109 12,448 -8,005 -39.14 3,221 -49.16 0.5725
2025-10-23 2025-09-30 13F GALLAGHER ARTHUR J COM 363576109 20,453 -36 -0.18 6,335 -3.40 1.1037
2025-07-28 2025-06-30 13F GALLAGHER ARTHUR J COM 363576109 20,489 26 0.13 6,559 -7.16 1.1969
2025-04-22 2025-03-31 13F GALLAGHER ARTHUR J COM 363576109 20,463 -100 -0.49 7,065 21.04 1.3998
2025-02-05 2024-12-31 13F GALLAGHER ARTHUR J COM 363576109 20,563 513 2.56 5,837 3.46 1.0837
2024-11-12 2024-09-30 13F GALLAGHER ARTHUR J COM 363576109 20,050 62 0.31 5,641 8.84 1.0295
2024-07-31 2024-06-30 13F GALLAGHER ARTHUR J COM 363576109 19,988 546 2.81 5,183 6.62 0.9964
2024-04-23 2024-03-31 13F GALLAGHER ARTHUR J COM 363576109 19,442 16,842 647.77 4,861 732.36 0.9598
2024-01-30 2023-12-31 13F GALLAGHER ARTHUR J COM 363576109 2,600 2,600 585 0.1234
2016-04-25 2016-03-31 13F GALLAGHER ARTHUR J COM 363576109 0 -3,200 -100.00 0 -100.00
2016-01-20 2015-12-31 13F GALLAGHER ARTHUR J COM 363576109 3,200 0 0.00 131 -0.76 0.0491
2015-10-27 2015-09-30 13F GALLAGHER ARTHUR J COM 363576109 3,200 0 0.00 132 -12.58 0.0513
2015-07-20 2015-06-30 13F GALLAGHER ARTHUR J COM 363576109 3,200 0 0.00 151 0.67 0.0526
2015-04-28 2015-03-31 13F GALLAGHER ARTHUR J COM 363576109 3,200 0 0.00 150 -0.66 0.0491
2015-01-22 2014-12-31 13F GALLAGHER ARTHUR J COM 363576109 3,200 0 0.00 151 4.14 0.0495
2014-10-23 2014-09-30 13F GALLAGHER ARTHUR J COM 363576109 3,200 3,200 145 0.0494
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.