Arthur J. Gallagher & Co.
MX ˙ BMV ˙ US3635761097
SecurityMX:AJG / Arthur J. Gallagher & Co.
InstitutionGuggenheim Capital Llc
Latest Disclosed Ownership3,591 shares
Latest Disclosed Value $ 777,738
Guggenheim Capital Llc reports 19.45% decrease in ownership of AJG / Arthur J. Gallagher & Co.

On May 15, 2026 - Guggenheim Capital Llc filed a 13F-HR form disclosing ownership of 3,591 shares of Arthur J. Gallagher & Co. (MX:AJG) valued at $777,738 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 17, 2026 disclosing 4,458 shares of Arthur J. Gallagher & Co.. This represents a change in shares of -19.45% 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 3,591 -867 -19.45 778 -32.61 0.0030
2026-02-17 2025-12-31 13F GALLAGHER ARTHUR J COM 363576109 4,458 -676 -13.17 1,154 -27.48 0.0041
2025-11-13 2025-09-30 13F GALLAGHER ARTHUR J COM 363576109 5,134 -2,319 -31.11 1,590 -33.33 0.0082
2025-08-13 2025-06-30 13F GALLAGHER ARTHUR J COM 363576109 7,453 -10 -0.13 2,386 -7.41 0.0189
2025-05-14 2025-03-31 13F GALLAGHER ARTHUR J COM 363576109 7,463 -1,201 -13.86 2,577 4.76 0.0237
2025-02-13 2024-12-31 13F GALLAGHER ARTHUR J COM 363576109 8,664 -464 -5.08 2,459 -4.24 0.0199
2024-11-13 2024-09-30 13F GALLAGHER ARTHUR J COM 363576109 9,128 -1,067 -10.47 2,568 -2.84 0.0180
2024-08-14 2024-06-30 13F GALLAGHER ARTHUR J COM 363576109 10,195 -1,997 -16.38 2,644 -13.29 0.0187
2024-05-14 2024-03-31 13F GALLAGHER ARTHUR J COM 363576109 12,192 1,009 9.02 3,048 21.24 0.0215
2024-02-14 2023-12-31 13F GALLAGHER ARTHUR J COM 363576109 11,183 1,031 10.16 2,515 8.69 0.0190
2023-11-14 2023-09-30 13F GALLAGHER ARTHUR J COM 363576109 10,152 -7,040 -40.95 2,314 -38.71 0.0199
2023-08-11 2023-06-30 13F GALLAGHER ARTHUR J COM 363576109 17,192 -20,540 -54.44 3,775 -47.71 0.0296
2023-05-11 2023-03-31 13F GALLAGHER ARTHUR J COM 363576109 37,732 -33,857 -47.29 7,219 -46.52 0.0608
2023-02-14 2022-12-31 13F GALLAGHER ARTHUR J COM 363576109 71,589 -10,562 -12.86 13,497 -4.04 0.1186
2022-11-14 2022-09-30 13F GALLAGHER ARTHUR J COM 363576109 82,151 -2,110 -2.50 14,065 2.39 0.1288
2022-08-15 2022-06-30 13F GALLAGHER ARTHUR J COM 363576109 84,261 -22,262 -20.90 13,737 -26.14 0.1084
2022-05-16 2022-03-31 13F GALLAGHER ARTHUR J COM 363576109 106,523 -7,076 -6.23 18,599 -3.50 0.1119
2022-02-14 2021-12-31 13F GALLAGHER ARTHUR J COM 363576109 113,599 628 0.56 19,274 14.77 0.1005
2021-11-15 2021-09-30 13F GALLAGHER ARTHUR J COM 363576109 112,971 -10,302 -8.36 16,793 -2.75 0.1008
2021-08-13 2021-06-30 13F GALLAGHER ARTHUR J COM 363576109 123,273 -4,630 -3.62 17,268 8.21 0.1017
2021-05-13 2021-03-31 13F GALLAGHER ARTHUR J COM 363576109 127,903 19,844 18.36 15,958 19.37 0.1048
2021-02-16 2020-12-31 13F GALLAGHER ARTHUR J COM 363576109 108,059 -10,763 -9.06 13,368 6.56 0.0838
2020-11-13 2020-09-30 13F GALLAGHER ARTHUR J COM 363576109 118,822 -13,030 -9.88 12,545 -2.40 0.0908
2020-08-14 2020-06-30 13F GALLAGHER ARTHUR J COM 363576109 131,852 14,937 12.78 12,854 34.89 0.0995
2020-06-02 2020-03-31 13F GALLAGHER ARTHUR J COM 363576109 116,915 -11,177 -8.73 9,529 -21.89 0.0960
2020-02-20 2019-12-31 13F/A-1 GALLAGHER ARTHUR J COM 363576109 128,092 1,498 1.18 12,199 7.58 0.0916
2020-02-14 2019-12-31 13F GALLAGHER ARTHUR J COM 363576109 128,092 1,498 12,199 72,301.0345
2020-02-20 2019-09-30 13F/A-1 GALLAGHER ARTHUR J COM 363576109 126,594 5,238 4.32 11,339 6.67 0.0906
2019-11-14 2019-09-30 13F GALLAGHER ARTHUR J COM 363576109 126,594 5,238 11,339 83,095.5180
2019-08-14 2019-06-30 13F GALLAGHER ARTHUR J COM 363576109 121,356 -2,039 -1.65 10,630 10.29 0.0865
2019-05-15 2019-03-31 13F GALLAGHER ARTHUR J COM 363576109 123,395 -43,494 -26.06 9,638 -21.64 0.0785
2019-02-14 2018-12-31 13F GALLAGHER ARTHUR J COM 363576109 166,889 -17,565 -9.52 12,300 -10.42 0.1042
2018-11-14 2018-09-30 13F GALLAGHER ARTHUR J COM 363576109 184,454 -23,224 -11.18 13,730 1.27 0.0895
2018-08-14 2018-06-30 13F GALLAGHER ARTHUR J COM 363576109 207,678 -491,585 -70.30 13,558 -71.79 0.0905
2018-05-15 2018-03-31 13F GALLAGHER ARTHUR J COM 363576109 699,263 -29,057 -3.99 48,060 4.28 0.1172
2018-02-14 2017-12-31 13F GALLAGHER ARTHUR J COM 363576109 728,320 -226,853 -23.75 46,087 -21.61 0.1092
2017-11-14 2017-09-30 13F GALLAGHER ARTHUR J COM 363576109 955,173 23,136 2.48 58,790 10.18 0.1381
2017-08-14 2017-06-30 13F GALLAGHER ARTHUR J COM 363576109 932,037 835 0.09 53,359 1.35 0.1413
2017-05-15 2017-03-31 13F GALLAGHER ARTHUR J COM 363576109 931,202 33,098 3.69 52,650 12.83 0.1427
2017-02-14 2016-12-31 13F GALLAGHER ARTHUR J COM 363576109 898,104 405,146 82.19 46,665 86.09 0.1335
2016-11-14 2016-09-30 13F GALLAGHER ARTHUR J COM 363576109 492,958 -226,783 -31.51 25,077 -26.80 0.0780
2016-08-15 2016-06-30 13F GALLAGHER ARTHUR J COM 363576109 719,741 401,064 125.85 34,260 141.73 0.1076
2016-05-16 2016-03-31 13F GALLAGHER ARTHUR J COM 363576109 318,677 -27,868 -8.04 14,173 -0.11 0.0447
2016-02-16 2015-12-31 13F GALLAGHER ARTHUR J COM 363576109 346,545 -61,203 -15.01 14,188 -15.70 0.0413
2015-11-16 2015-09-30 13F GALLAGHER ARTHUR J COM 363576109 407,748 366,690 893.10 16,831 766.24 0.0518
2015-08-14 2015-06-30 13F GALLAGHER ARTHUR J COM 363576109 41,058 -61,786 -60.08 1,943 -59.59 0.0048
2015-05-18 2015-03-31 13F/A-1 GALLAGHER ARTHUR J COM 363576109 102,844 -37,219 -26.57 4,808 -27.09 0.0114
2015-05-15 2015-03-31 13F GALLAGHER ARTHUR J COM 363576109 102,844 4,808
2015-02-17 2014-12-31 13F GALLAGHER ARTHUR J COM 363576109 140,063 8,119 6.15 6,594 10.23 0.0165
2014-11-14 2014-09-30 13F GALLAGHER ARTHUR J COM 363576109 131,944 40,678 44.57 5,982 40.62 0.0144
2014-08-14 2014-06-30 13F GALLAGHER ARTHUR J COM 363576109 91,266 5,115 5.94 4,254 3.81 0.0108
2014-05-16 2014-03-31 13F GALLAGHER ARTHUR J COM 363576109 86,151 -28,858 -25.09 4,098 -24.05 0.0117
2014-02-14 2013-12-31 13F GALLAGHER ARTHUR J COM 363576109 115,009 -1,674 -1.43 5,396 5.97 0.0164
2013-11-14 2013-09-30 13F GALLAGHER ARTHUR J COM 363576109 116,683 13,803 13.42 5,092 13.31 0.0183
2013-08-22 2013-06-30 13F/A-1 GALLAGHER ARTHUR J COM 363576109 102,880 102,880 4,494 0.0189
2013-08-14 2013-06-30 13F GALLAGHER ARTHUR J COM 363576109 102,880 4,494 0.0189
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.