SEC Form 4
Aon plc (AON) insider trading
In the 12 months to Oct 24, 2026, one AON insider reported open-market sales of $7.8M across 6 filings; one director bought $7.8M.
Latest filing · Last 12 months · Source: SEC EDGAR · How we count
- Open-market sales
- $7.8M
- 6 filings · 1 insider
- Open-market purchases
- $7.8M
- 2 filings · Lester B. Knight, Director
- Pre-arranged sales (10b5-1)
- 4 of 6
- $3.3M of $7.8M sold (43%)
Who traded AON, and when
- Purchase
- Sale
- Sale, pre-arranged (10b5-1)
AON daily close from Oct 24, 2025 to Oct 23, 2026, between $269.45 and $381.26, last $303.52. 6 sale and 2 purchase filings by 2 insiders, marked at their filing dates. Lester B. Knight, Director: bought $7.8M across 2 filings, first filed Feb 12, 2026, last Sep 3, 2026. Darren Zeidel, General Counsel: sold $7.8M across 6 filings, first filed Nov 7, 2025, last Jul 30, 2026.
Largest mark · tap a row for others
Lester B. Knight · Director
Purchase $6,549,688
20,000 shares
Filed Sep 3, 2026 · traded Sep 2
Close on filing date $327.00
Lester B. Knight · Director
Director
$7.8M boughtDarren Zeidel · General Counsel
General Counsel
$7.8M soldHas Aon plc's CEO sold stock?
No. Lori Goltermann and Andy Marcell and Gregory C. Case (CEOs) made no open-market sales filed as CEO in the last 12 months.
Open-market trades
8 filings in the last 12 months| Insider | Role | Sold | Bought | Filings | Pre-arranged (10b5-1) | Last filed |
|---|---|---|---|---|---|---|
| Lester B. Knight | Director | — | $7.8M | 2 | — | |
| Darren Zeidel | General Counsel | $7.8M | — | 6 | 43% of sales |
| Filed | Insider | Type | Shares | Value | Held after | Source |
|---|---|---|---|---|---|---|
traded | Lester B. Knight Director | Purchase | 20,000 ordinary shares | $6.5M | 162,633 | |
traded | Darren Zeidel General Counsel | SalePre-arranged (10b5-1) | 1,900 ordinary shares | $717.8K | 11,979 | |
traded | Darren Zeidel General Counsel | SalePre-arranged (10b5-1) | 1,950 ordinary shares | $725.5K | 13,404 | |
traded | Darren Zeidel General Counsel | SalePre-arranged (10b5-1) | 600 ordinary shares | $216.0K | 15,354 | |
traded | Darren Zeidel General Counsel | Sale | 4,300 ordinary shares | $1.4M | 15,954 | |
traded | Darren Zeidel General Counsel | SalePre-arranged (10b5-1) | 5,040 ordinary shares | $1.6M | 20,254 | |
traded | Lester B. Knight Director | Purchase | 4,000 ordinary shares | $1.3M | 143,000 | |
traded | Darren Zeidel General Counsel | Sale | 8,800 ordinary shares | $3.0M | 20,253 |
Shares are as filed (ordinary shares or ADS); values are as converted to US$ in the filing.
GET /stocks/filings/vX/form-4?tickers=AON&filing_date.gte=2025-10-24&sort=filing_date.desc&limit=500{
"status": "OK",
"results": [
{
"tickers": [
"AON"
],
"issuer_cik": "0000315293",
"owner_cik": "0001023262",
"accession_number": "0001193125-26-382419",
"form_type": "4",
"filing_date": "2026-09-03",
"period_of_report": "2026-09-02",
"issuer_name": "Aon plc",
"issuer_trading_symbol": "AON",
"owner_name": "KNIGHT LESTER B",
"is_director": true,
"is_officer": false,
"is_ten_percent_owner": false,
"is_other": false,
"security_type": "non_derivative",
"record_type": "transaction",
"security_title": "Class A Ordinary Stock",
"transaction_timeliness": "O",
"aff_10b5_one": false,
"transaction_date": "2026-09-02",
"transaction_code": "P",
"equity_swap_involved": false,
"transaction_shares": 367,
"transaction_price_per_share": 330.51,
"transaction_acquired_disposed": "A",
"shares_owned_following_transaction": 163000,
"transaction_value": 121297.17,
"direct_or_indirect": "I",
"nature_of_ownership": "By Family Partnership",
"footnotes": [
{
"id": "F6",
"description": "The price reported is a weighted average price. Shares were purchased in a series of transactions within the same trading day at prices ranging from $330.09 to $330.88, inclusive. Full information regarding the number of shares purchased at each separate price is available upon request by the Commission staff, the issuer, or a security holder of the issuer."
}
]
},
{
"tickers": [
"AON"
],
"issuer_cik": "0000315293",
"owner_cik": "0001023262",
"accession_number": "0001193125-26-382419",
"form_type": "4",
"filing_date": "2026-09-03",
"period_of_report": "2026-09-02",
"issuer_name": "Aon plc",
"issuer_trading_symbol": "AON",
"owner_name": "KNIGHT LESTER B",
"is_director": true,
"is_officer": false,
"is_ten_percent_owner": false,
"is_other": false,
"security_type": "non_derivative",
"record_type": "transaction",
"security_title": "Class A Ordinary Stock",
"transaction_timeliness": "O",
"aff_10b5_one": false,
"transaction_date": "2026-09-02",
"transaction_code": "P",
"equity_swap_involved": false,
"transaction_shares": 7212,
"transaction_price_per_share": 327.52,
"transaction_acquired_disposed": "A",
"shares_owned_following_transaction": 157048,
"transaction_value": 2362074.2399999998,
"direct_or_indirect": "I",
"nature_of_ownership": "By Family Partnership",
"footnotes": [
{
"id": "F3",
"description": "The price reported is a weighted average price. Shares were purchased in a series of transactions within the same trading day at prices ranging from $327.04 to $328.03, inclusive. Full information regarding the number of shares purchased at each separate price is available upon request by the Commission staff, the issuer, or a security holder of the issuer."
}
]
}
]
}
// trimmed to 2 resultsThe response includes every Form 4 record; this page keeps open-market purchases and sales on common stock and removes duplicate joint-filer rows.
Other insider activity (not market trades) · 89 records
- Option exercises18 records
- Tax withholding37 records
- Grants and awards20 records
- Gifts14 records
Reported on Form 4 but not purchases or sales in the market, so not counted in the totals above.
Build this yourself
This page joins two Massive endpoints: Form 4 filings and daily prices. Ask an agent to watch for new filings:
Using the Massive API (massive.com/docs/llms.txt), check Form 4 filings for AON every day with transaction_code=P and tell me when an insider files an open-market purchase, with their role, shares, price and the filing link.
How to read this page
- Open-market purchase or sale
- A buy or sell of the company's stock at market price. Grants, option exercises, shares withheld for tax, gifts and employee stock plan purchases are listed separately and not counted.
- Pre-arranged (10b5-1)
- The insider marked the filing as made under a trading plan set up in advance (SEC Rule 10b5-1). The mark covers the whole filing, and an unmarked filing may still be under a plan.
- Filing date
- Insiders have two business days to report a trade. Totals and the chart use the filing date, when the trade became public.