Aon plc
US ˙ NYSE ˙ IE00BLP1HW54

SecurityAON / Aon plc
InstitutionChicago Capital, LLC
Latest Disclosed Ownership3,123 shares
Latest Disclosed Value $ 1,008,042
Chicago Capital, LLC reports 51.75% increase in ownership of AON / Aon plc

On April 23, 2026 - Chicago Capital, LLC filed a 13F-HR form disclosing ownership of 3,123 shares of Aon plc (US:AON) valued at $1,008,042 USD as of March 31, 2026. The entity filed a previous 13F-HR on January 26, 2026 disclosing 2,058 shares of Aon plc. This represents a change in shares of 51.75% during the quarter. The current value of the position is $985,619 USD.

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)
2026-04-23 2026-03-31 13F AON SHS CL A G0403H108 3,123 1,065 51.75 1,008 38.84 0.0272
2026-01-26 2025-12-31 13F AON SHS CL A G0403H108 2,058 0 0.00 726 -0.95 0.0179
2025-10-22 2025-09-30 13F AON SHS CL A G0403H108 2,058 0 0.00 734 -0.14 0.0181
2025-07-17 2025-06-30 13F AON SHS CL A G0403H108 2,058 0 0.00 734 -10.60 0.0181
2025-04-17 2025-03-31 13F AON SHS CL A G0403H108 2,058 133 6.91 821 18.81 0.0232
2025-01-24 2024-12-31 13F AON SHS CL A G0403H108 1,925 0 0.00 691 3.75 0.0183
2024-10-18 2024-09-30 13F AON SHS CL A G0403H108 1,925 -325 -14.44 666 0.91 0.0185
2024-08-06 2024-06-30 13F AON SHS CL A G0403H108 2,250 0 0.00 661 -12.00 0.0196
2024-04-15 2024-03-31 13F AON SHS CL A G0403H108 2,250 0 0.00 751 14.68 0.0229
2024-01-22 2023-12-31 13F AON SHS CL A G0403H108 2,250 -325 -12.62 655 -21.58 0.0236
2023-10-25 2023-09-30 13F AON SHS CL A G0403H108 2,575 0 0.00 835 -6.08 0.0390
2023-07-20 2023-06-30 13F AON SHS CL A G0403H108 2,575 -25 -0.96 889 8.42 0.0401
2023-04-18 2023-03-31 13F AON SHS CL A G0403H108 2,600 0 0.00 820 5.00 0.0408
2023-01-20 2022-12-31 13F AON SHS CL A G0403H108 2,600 0 0.00 780 12.07 0.0432
2022-10-14 2022-09-30 13F AON SHS CL A G0403H108 2,600 0 0.00 696 -0.71 0.0403
2022-07-21 2022-06-30 13F AON SHS CL A G0403H108 2,600 0 0.00 701 -17.24 0.0387
2022-04-21 2022-03-31 13F AON SHS CL A G0403H108 2,600 0 0.00 847 8.45 0.0365
2022-01-20 2021-12-31 13F AON SHS CL A G0403H108 2,600 0 0.00 781 5.11 0.0291
2021-10-28 2021-09-30 13F AON SHS CL A G0403H108 2,600 0 0.00 743 19.65 0.0282
2021-07-22 2021-06-30 13F AON SHS CL A G0403H108 2,600 0 0.00 621 3.85 0.0243
2021-04-13 2021-03-31 13F AON SHS CL A G0403H108 2,600 0 0.00 598 8.93 0.0252
2021-01-25 2020-12-31 13F AON SHS CL A G0403H108 2,600 0 0.00 549 2.43 0.0245
2020-10-13 2020-09-30 13F AON SHS CL A G0403H108 2,600 0 0.00 536 6.99 0.0276
2020-07-29 2020-06-30 13F AON SHS CL A G0403H108 2,600 2,600 501 0.0290
2020-04-21 2020-03-31 13F AON SHS CL A G0408V102 0 -2,600 -100.00 0 -100.00
2020-01-14 2019-12-31 13F AON SHS CL A G0408V102 2,600 0 0.00 542 7.75 0.0331
2019-10-28 2019-09-30 13F AON COMMON G0408V102 2,600 0 0.00 503 0.20 0.0337
2019-07-11 2019-06-30 13F AON COMMON G0408V102 2,600 0 0.00 502 13.06 0.0321
2019-04-23 2019-03-31 13F AON COMMON G0408V102 2,600 -1,121 -30.13 444 -17.93 0.0302
2019-02-11 2018-12-31 13F AON COM G0408V102 3,721 1,121 43.12 541 35.25 0.0441
2018-11-02 2018-09-30 13F AON COM G0408V102 2,600 -7,000 -72.92 400 -69.63 0.0277
2018-07-19 2018-06-30 13F AON COM G0408V102 9,600 7,000 269.23 1,317 260.82 0.1062
2018-05-09 2018-03-31 13F Aon COM G0408V102 2,600 2,600 365 0.0487
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.