SEC EDGAR · Insider purchase
AON: KNIGHT LESTER B reported buying shares
6 reported purchases of non-derivative securities. Code P includes open-market and private purchases; it does not establish motive.
Follow AON- Became public
- Sep 3, 2026, 8:33 PM EDT
- Event / period date
- Sep 2, 2026
- Collected
- Nov 9, 2026, 4:46 AM EST
Why this is connected
This filing identifies Aon plc as the issuer of the security. The company's SEC identifier connects it to AON.
Reported transactions
KNIGHT LESTER B (Director)
1,739 shares · Class A Ordinary Stock
Sep 2, 2026 · $325.63 per share
5,097 shares · Class A Ordinary Stock
Sep 2, 2026 · $326.53 per share
7,212 shares · Class A Ordinary Stock
Sep 2, 2026 · $327.52 per share
4,145 shares · Class A Ordinary Stock
Sep 2, 2026 · $328.34 per share
1,440 shares · Class A Ordinary Stock
Sep 2, 2026 · $329.69 per share
367 shares · Class A Ordinary Stock
Sep 2, 2026 · $330.51 per share
Value calculated from the reported shares and prices: $6,549,688.29.
Code P covers open-market and private purchases. Grants, option exercises, and tax withholding are excluded from purchase results. Read the source footnotes for ownership and pricing details.
Source evidence
Read the source excerpt or record
<?xml version="1.0"?>
<ownershipDocument>
<schemaVersion>X0609</schemaVersion>
<documentType>4</documentType>
<periodOfReport>2026-09-02</periodOfReport>
<issuer>
<issuerCik>0000315293</issuerCik>
<issuerName>Aon plc</issuerName>
<issuerTradingSymbol>AON</issuerTradingSymbol>
<issuerForeignTradingSymbol></issuerForeignTradingSymbol>
</issuer>
<reportingOwner>
<reportingOwnerId>
<rptOwnerCik>0001023262</rptOwnerCik>
<rptOwnerName>KNIGHT LESTER B</rptOwnerName>
</reportingOwnerId>
<reportingOwnerAddress>
<rptOwnerNonUSAddressFlag>false</rptOwnerNonUSAddressFlag>
<rptOwnerStreet1>200 EAST RANDOLPH ST.</rptOwnerStreet1>
<rptOwnerStreet2></rptOwnerStreet2>
<rptOwnerCity>CHICAGO</rptOwnerCity>
<rptOwnerState>IL</rptOwnerState>
<rptOwnerZipCode>60601</rptOwnerZipCode>
<rptOwnerStateDescription></rptOwnerStateDescription>
</reportingOwnerAddress>
<reportingOwnerRelationship>
<isDirector>true</isDirector>
<isOfficer>false</isOfficer>
<isTenPercentOwner>false</isTenPercentOwner>
<isOther>false</isOther>
</reportingOwnerRelationship>
</reportingOwner>
<aff10b5One>false</aff10b5One>
<nonDerivativeTable>
<nonDerivativeTransaction>
<securityTitle>
<value>Class A Ordinary Stock</value>
</securityTitle>
<transactionDate>
<value>2026-09-02</value>
</transactionDate>
<transactionCoding>
<transactionFormType>4</transactionFormType>
<transactionCode>P</transactionCode>
<equitySwapInvolved>false</equitySwapInvolved>
</transactionCoding>
<transactionAmounts>
<transactionShares>
<value>1739</value>
</transactionShares>
<transactionPricePerShare>
<value>325.63</value>
<footnoteId id="F1"/>
</transactionPricePerShare>
<transactionAcquiredDisposedCode>
<value>A</value>
</transactionAcquiredDisposedCode>
</transactionAmounts>
<postTransactionAmounts>
<sharesOwnedFollowingTransaction>
<value>144739</value>
</sharesOwnedFollowingTransaction>
</postTransactionAmounts>
<ownershipNature>
<directOrIndirectOwnership>
<value>I</value>
</directOrIndirectOwnership>
<natureOfOwnership>
<value>By Family Partnership</value>
</natureOfOwnership>
</ownershipNature>
</nonDerivativeTransaction>
<nonDerivativeTransaction>
<securityTitle>
<value>Class A Ordinary Stock</value>
</securityTitle>
<transactionDate>
<value>2026-09-02</value>
</transactionDate>
<transactionCoding>
<transactionFormType>4</transactionFormType>
<transactionCode>P</transactionCode>
<equitySwapInvolved>false</equitySwapInvolved>
</transactionCoding>
<transactionAmounts>
<transactionShares>
<value>5097</value>
</transactionShares>
<transactionPricePerShare>
<value>326.53</value>
<footnoteId id="F2"/>
</transactionPricePerShare>
<transactionAcquiredDisposedCode>
<value>A</value>
</transactionAcquiredDisposedCode>
</transactionAmounts>
<postTransactionAmounts>
<sharesOwnedFollowingTransaction>
<value>149836</value>
</sharesOwnedFollowingTransaction>
</postTransactionAmounts>
<ownershipNature>
<directOrIndirectOwnership>
<value>I</value>
</directOrIndirectOwnership>
<natureOfOwnership>
<value>By Family Partnership</value>
</natureOfOwnership>
</ownershipNature>
</nonDerivativeTransaction>
<nonDerivativeTransaction>
<securityTitle>
<value>Class A Ordinary Stock</value>
</securityTitle>
<transactionDate>
<value>2026-09-02</value>
</transactionDate>
<transactionCoding>
<transactionFormType>4</transactionFormType>
<transactionCode>P</transactionCode>
<equitySwapInvolved>false</equitySwapInvolved>
</transactionCoding>
<transactionAmounts>
<transactionShares>
<value>7212</value>
</transactionShares>
<transactionPricePerShare>
<value>327.52</value>
<footnoteId id="F3"/>
</transactionPricePerShare>
<transactionAcquiredDisposedCode>
<value>A</value>
</transactionAcquiredDisposedCode>
</transactionAmounts>
<postTransactionAmounts>
<sharesOwnedFollowingTransaction>
<value>157048</value>
</sharesOwnedFollowingTransaction>
</postTransactionAmounts>
<ownershipNature>
<directOrIndirectOwnership>
<value>I</value>
</directOrIndirectOwnership>
<natureOfOwnership>
<value>By Family Partnership</value>
</natureOfOwnership>
</ownershipNature>
</nonDerivativeTransaction>
<nonDerivativeTransaction>
<securityTitle>
<value>Class A Ordinary Stock</value>
</securityTitle>
<transactionDate>
<value>2026-09-02</value>
</transactionDate>
<transactionCoding>
<transactionFormType>4</transactionFormType>
<transactionCode>P</transactionCode>
<equitySwapInvolved>false</equitySwapInvolved>
</transactionCoding>
<transactionAmounts>
<transactionShares>
<value>4145</value>
</transactionShares>
<transactionPricePerShare>
<value>328.34</value>
<footnoteId id="F4"/>
</transactionPricePerShare>
<transactionAcquiredDisposedCode>
<value>A</value>
</transactionAcquiredDisposedCode>
</transactionAmounts>
<postTransactionAmounts>
<sharesOwnedFollowingTransaction>
<value>161193</value>
</sharesOwnedFollowingTransaction>
</postTransactionAmounts>
<ownershipNature>
<directOrIndirectOwnership>
<value>I</value>
</directOrIndirectOwnership>
<natureOfOwnership>
<value>By Family Partnership</value>
</natureOfOwnership>
</ownershipNature>
</nonDerivativeTransaction>
<nonDerivativeTransaction>
<securityTitle>
<value>Class A Ordinary Stock</value>
</securityTitle>
<transactionDate>
<value>2026-09-02</value>
</transactionDate>
<transactionCoding>
<transactionFormType>4</transactionFormType>
<transactionCode>P</transactionCode>
<equitySwapInvolved>false</equitySwapInvolved>
</transactionCoding>
<transactionAmounts>
<transactionShares>
<value>1440</value>
</transactionShares>
<transactionPricePerShare>
<value>329.69</value>
<footnoteId id="F5"/>
</transactionPricePerShare>
<transactionAcquiredDisposedCode>
<value>A</value>
</transactionAcquiredDisposedCode>
</transactionAmounts>
<postTransactionAmounts>
<sharesOwnedFollowingTransaction>
<value>162633</value>
</sharesOwnedFollowingTransaction>
</postTransactionAmounts>
<ownershipNature>
<directOrIndirectOwnership>
<value>I</value>
</directOrIndirectOwnership>
<natureOfOwnership>
<value>By Family Partnership</value>
</natureOfOwnership>
</ownershipNature>
</nonDerivativeTransaction>
<nonDerivativeTransaction>
<securityTitle>
<value>Class A Ordinary Stock</value>
</securityTitle>
<transactionDate>
<value>2026-09-02</value>
</transactionDate>
<transactionCoding>
<transactionFormType>4</transactionFormType>
<transactionCode>P</transactionCode>
<equitySwapInvolved>false</equitySwapInvolved>
</transactionCoding>
<transactionAmounts>
<transactionShares>
<value>367</value>
</transactionShares>
<transactionPricePerShare>
<value>330.51</value>
<footnoteId id="F6"/>
</transactionPricePerShare>
<transactionAcquiredDisposedCode>
<value>A</value>
</transactionAcquiredDisposedCode>
</transactionAmounts>
<postTransactionAmounts>
<sharesOwnedFollowingTransaction>
<value>163000</value>
</sharesOwnedFollowingTransaction>
</postTransactionAmounts>
<ownershipNature>
<directOrIndirectOwnership>
<value>I</value>
</directOrIndirectOwnership>
<natureOfOwnership>
<value>By Family Partnership</value>
</natureOfOwnership>
</ownershipNature>
</nonDerivativeTransaction>
<nonDerivativeHolding>
<securityTitle>
<value>Class A Ordinary Stock</value>
</securityTitle>
<postTransactionAmounts>
<sharesOwnedFollowingTransaction>
<value>5227</value>
</sharesOwnedFollowingTransaction>
</postTransactionAmounts>
<ownershipNature>
<directOrIndirectOwnership>
<value>D</value>
</directOrIndirectOwnership>
</ownershipNature>
</nonDerivativeHolding>
<nonDerivativeHolding>
<securityTitle>
<value>Class A Ordinary Stock</value>
</securityTitle>
<postTransactionAmounts>
<sharesOwnedFollowingTransaction>
<value>124604</value>
</sharesOwnedFollowingTransaction>
</postTransactionAmounts>
<ownershipNature>
<directOrIndirectOwnership>
<value>I</value>
</directOrIndirectOwnership>
<natureOfOwnership>
<value>By Wife</value>
</natureOfOwnership>
</ownershipNature>
</nonDerivativeHolding>
<nonDerivativeHolding>
<securityTitle>
<value>Class A Ordinary Stock</value>
</securityTitle>
<postTransactionAmounts>
<sharesOwnedFollowingTransaction>
<value>26033</value>
</sharesOwnedFollowingTransaction>
</postTransactionAmounts>
<ownershipNature>
<directOrIndirectOwnership>
<value>I</value>
</directOrIndirectOwnership>
<natureOfOwnership>
<value>Personal Revocable Trust</value>
</natureOfOwnership>
</ownershipNature>
</nonDerivativeHolding>
</nonDerivativeTable>
<footnotes>
<footnote id="F1">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 $325.03 to $326.02, 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.</footnote>
<footnote id="F2">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 $326.03 to $327.02, 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.</footnote>
<footnote id="F3">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.</footnote>
<footnote id="F4">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 $328.04 to $329.03, 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.</footnote>
<footnote id="F5">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 $329.08 to $330.07, 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.</footnote>
<footnote id="F6">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.</footnote>
</footnotes>
<ownerSignature>
<signatureName>/s/ Colby Alexis - Colby Alexis pursuant to a power of attorney from Lester Knight</signatureName>
<signatureDate>2026-09-03</signatureDate>
</ownerSignature>
</ownershipDocument>
Price change after we could observe it
+0.06% AON
Adjusted closing prices from Nov 10, 2026 to Nov 11, 2026. SPY changed 1.32% over the same dates. The start is the first available close after both publication and collection. This is a price comparison, not an executed trade, investor profit, or a backtested strategy.
Congressional trading in AON
These disclosures provide context. Their presence does not establish a link between a trader and the event.
- Oct 7, 2026$1K–$15K
- Jul 21, 2026$1K–$15K
Sen. Alan Armstrong (R-OK)
$1K–$15K · Traded Mar 27, 2026 · disclosed Jul 21, 2026 · filed 116 days later
- Feb 6, 2026$1K–$15K
- Feb 6, 2026$1K–$15K
Rep. Ro Khanna (D-CA-17)
$1K–$15K · Traded Jan 13, 2026 · disclosed Feb 6, 2026 · Spouse
- Sep 12, 2025$1K–$15K
Rep. Ro Khanna (D-CA-17)
$1K–$15K · Traded Aug 26, 2025 · disclosed Sep 12, 2025 · Dependent
- Jun 22, 2025$15K–$50K
- Jun 17, 2025$1K–$15K
Rep. Thomas H. Kean, Jr. (R-NJ-7)
$1K–$15K · Traded May 27, 2025 · disclosed Jun 17, 2025
- Apr 11, 2025$15K–$50K
Rep. Jefferson Shreve (R-IN-6)
$15K–$50K · Traded Mar 13, 2025 · disclosed Apr 11, 2025
Original documents control. Public records can be amended, and company connections may require interpretation. Nothing here is investment advice.