AON
Aon PLC
Aon PLC historical holders
total: 18
Viking Global Investors Aon PLC transactions over time
- Total transactions:
- 31
- New positions:
- 7
- Sold out:
- 6
- Added:
- 12
- Reduced:
- 6
- Held since:
- 2025 Q3
- Held for:
- 3 quarters
- Latest activity:
- 2026 Q1
Ole Andreas Halvorsen has been an institutional investor in Aon PLC (AON) since 2014 Q3. According to 2026 Q1 report, Ole Andreas Halvorsen holds 1,087,114 shares with a market value of roughly $350.90M representing 0.98% of their equity portfolio. The fund/company first acquired AON in 2014 Q3, initially purchasing about 1.66M shares. Ole Andreas Halvorsen later completely sold out the position and reinvested in AON again in 2025 Q3. Since the initial investment, Viking Global Investors has made 30 more transactions in this position.
Does Ole Andreas Halvorsen still hold AON?
Yes, Ole Andreas Halvorsen continues to hold Aon PLC (AON). According to their 2026 Q1 report, they maintain a position of 1,087,114 shares valued at approximately $350.90M, representing 0.98% of their equity portfolio.
When did Ole Andreas Halvorsen first invest in AON?
Ole Andreas Halvorsen first invested in Aon PLC (AON) in 2014 Q3 at the reported quarter-end price of $87.67 per share, acquiring 1,662,625 shares in their initial purchase.
What is Ole Andreas Halvorsen's average cost basis for AON?
Based on historical transaction data, Ole Andreas Halvorsen's estimated cost basis for Aon PLC (AON) is approximately $350.61 per share. This represents their average reported price* across all buy transactions.
Has Ole Andreas Halvorsen reinvested in AON after selling?
Yes, Ole Andreas Halvorsen has shown renewed interest in Aon PLC (AON). After completely selling their position, they reinitiated an investment in 2025 Q3, demonstrating continued conviction in this ticker.
Estimated cost basis*
- Weighted AVG buy price:
- $350.61
- Weighted AVG sell price:
- $352.88
AON transactions history by Viking Global Investors
31 results
| Period |
% of portfolio |
Shares held after* |
Reported price* |
Value* |
% (shares) of activity |
% change to portfolio |
|---|---|---|---|---|---|---|
|
2026 Q1
|
0.98%
|
1,087,114
|
$322.78
|
$350,898,657
|
+38.72% (+303,464)
|
+0.27%
|
|
2025 Q4
|
0.73%
|
783,650
|
$352.88
|
$276,534,412
|
-44.60% (-630,968)
|
-0.58%
|
|
2025 Q3
|
1.31%
|
1,414,618
|
$356.58
|
$504,424,486
|
new
|
+1.31%
|
|
2025 Q1
|
0.00%
|
0
|
$359.16
|
|
-100% (-720,364)
|
-0.84%
|
|
2024 Q4
|
0.84%
|
720,364
|
$359.16
|
$258,725,934
|
+27.94% (+157,337)
|
+0.18%
|
|
2024 Q3
|
0.71%
|
563,027
|
$345.99
|
$194,801,712
|
new
|
+0.71%
|
|
2022 Q3
|
0.00%
|
0
|
$269.68
|
|
-100% (-704,639)
|
-0.87%
|
|
2022 Q2
|
0.87%
|
704,639
|
$269.68
|
$190,027,000
|
-55.77% (-888,441)
|
-0.97%
|
|
2022 Q1
|
2.10%
|
1,593,080
|
$325.63
|
$518,755,000
|
+5.47% (+82,563)
|
+0.11%
|
|
2021 Q4
|
1.31%
|
1,510,517
|
$300.56
|
$454,001,000
|
new
|
+1.31%
|
|
2021 Q3
|
0.00%
|
$238.76
|
-100% (-2,903,054)
|
|||
|
2021 Q2
|
2.10%
|
$238.76
|
+34.74% (+748,565)
|
|||
|
2021 Q1
|
1.48%
|
$230.11
|
-16.19% (-416,131)
|
|||
|
2020 Q4
|
1.49%
|
$211.27
|
-14.68% (-442,286)
|
|||
|
2020 Q3
|
2.25%
|
$206.30
|
+1.92% (+56,877)
|
|||
|
2020 Q2
|
2.46%
|
$192.60
|
+29.05% (+665,509)
|
|||
|
2020 Q1
|
1.97%
|
$165.04
|
+196.69% (+1,518,493)
|
|||
|
2019 Q4
|
0.75%
|
$208.29
|
-2.61% (-20,730)
|
|||
|
2019 Q3
|
0.80%
|
$193.57
|
-6.93% (-59,021)
|
|||
|
2019 Q2
|
0.74%
|
$192.98
|
+30.20% (+197,554)
|
|||
|
2019 Q1
|
0.64%
|
$170.70
|
+24.90% (+130,417)
|
|||
|
2018 Q4
|
0.43%
|
$145.36
|
+8.48% (+40,939)
|
|||
|
2018 Q3
|
0.41%
|
$153.78
|
new
|
|||
|
2016 Q3
|
0.00%
|
$109.23
|
-100% (-703,995)
|
|||
|
2016 Q2
|
0.33%
|
$109.23
|
+23.17% (+132,439)
|
|||
|
2016 Q1
|
0.26%
|
$104.45
|
new
|
|||
|
2015 Q3
|
0.00%
|
$99.68
|
-100% (-1,912,946)
|
|||
|
2015 Q2
|
0.72%
|
$99.68
|
+124.06% (+1,059,185)
|
|||
|
2015 Q1
|
0.32%
|
$96.12
|
new
|
|||
|
2014 Q4
|
0.00%
|
$87.67
|
-100% (-1,662,625)
|
|||
|
2014 Q3
|
0.59%
|
$87.67
|
new
|
|||
* Shares, change to shares, sold shares, shares held after: split-adjusted.
* Reported price: this doesn't represent the actual buy or sell price. It is the split-adjusted price of the security as of the last day of the reported period.
If the security is completely sold out, we show the reported split-adjusted price prior to the actual period.
If the security is completely sold out, we show the reported split-adjusted price prior to the actual period.
* Estimated cost basis: based on "Reported price*" (not earlier than 2013 Q2). Calculation starts from the latest "new buy" activity to the latest "close out" activity (if any).
* Value or Price: If the security is completely sold out, we show the reported value (or price) prior to the actual period.
* New buy or own: this means there is no earlier reporting (for us or in general). So we can't know if the actual purchase of the security happened at the reported period or earlier.