<SEC-DOCUMENT>0001193125-19-152706.txt : 20190521
<SEC-HEADER>0001193125-19-152706.hdr.sgml : 20190521
<ACCEPTANCE-DATETIME>20190521160557
ACCESSION NUMBER:		0001193125-19-152706
CONFORMED SUBMISSION TYPE:	DEFA14A
PUBLIC DOCUMENT COUNT:		1
FILED AS OF DATE:		20190521
DATE AS OF CHANGE:		20190521
EFFECTIVENESS DATE:		20190521

FILER:

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Aon plc
		CENTRAL INDEX KEY:			0000315293
		STANDARD INDUSTRIAL CLASSIFICATION:	INSURANCE AGENTS BROKERS & SERVICES [6411]
		IRS NUMBER:				363051915
		STATE OF INCORPORATION:			X0
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		DEFA14A
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-07933
		FILM NUMBER:		19842405

	BUSINESS ADDRESS:	
		STREET 1:		THE LEADENHALL BUILDING
		STREET 2:		122 LEADENHALL STREET
		CITY:			LONDON
		STATE:			X0
		ZIP:			EC3V 4AN
		BUSINESS PHONE:		(44) 20 7623 5500

	MAIL ADDRESS:	
		STREET 1:		THE LEADENHALL BUILDING
		STREET 2:		122 LEADENHALL STREET
		CITY:			LONDON
		STATE:			X0
		ZIP:			EC3V 4AN

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	AON CORP
		DATE OF NAME CHANGE:	19920703

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	COMBINED INTERNATIONAL CORP
		DATE OF NAME CHANGE:	19870504
</SEC-HEADER>
<DOCUMENT>
<TYPE>DEFA14A
<SEQUENCE>1
<FILENAME>d723609ddefa14a.htm
<DESCRIPTION>DEFA14A
<TEXT>
<HTML><HEAD>
<TITLE>DEFA14A</TITLE>
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<Center><DIV STYLE="width:8.5in" align="left">
 <P STYLE="line-height:1.0pt;margin-top:0pt;margin-bottom:0pt;border-bottom:1px solid #000000">&nbsp;</P>
<P STYLE="line-height:3.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1px solid #000000">&nbsp;</P> <P STYLE="margin-top:4pt; margin-bottom:0pt; font-size:18pt; font-family:Times New Roman" ALIGN="center"><B>SCHEDULE 14A </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>(RULE <FONT STYLE="white-space:nowrap">14a-101)</FONT> </B></P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><center>
<P STYLE="line-height:6.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1.00pt solid #000000;width:21%">&nbsp;</P></center> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:12pt; font-family:Times New Roman" ALIGN="center"><B>INFORMATION
REQUIRED IN PROXY STATEMENT </B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:12pt; font-family:Times New Roman" ALIGN="center"><B>SCHEDULE 14A INFORMATION </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:12pt; font-family:Times New Roman" ALIGN="center"><B>PROXY STATEMENT PURSUANT TO SECTION 14(a) OF THE </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:12pt; font-family:Times New Roman" ALIGN="center"><B>SECURITIES EXCHANGE ACT OF 1934 </B></P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><center>
<P STYLE="line-height:6.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1.00pt solid #000000;width:21%">&nbsp;</P></center> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Filed by the
registrant&nbsp;&nbsp;&#9746;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Filed by a Party other than the registrant&nbsp;&nbsp;&#9744; </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Check the appropriate box: </P> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%" VALIGN="top" ALIGN="left">&#9744;</TD>
<TD ALIGN="left" VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman; " ALIGN="left">Preliminary proxy statement </P></TD></TR></TABLE>
<P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%" VALIGN="top" ALIGN="left">&#9744;</TD>
<TD ALIGN="left" VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman; " ALIGN="left"><B>Confidential, for Use of the Commission Only</B><B></B><B>&nbsp;(as permitted by Rule <FONT
STYLE="white-space:nowrap">14a-6(e)(2))</FONT></B> </P></TD></TR></TABLE> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%" VALIGN="top" ALIGN="left">&#9744;</TD>
<TD ALIGN="left" VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman; " ALIGN="left">Definitive proxy statement </P></TD></TR></TABLE>
<P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%" VALIGN="top" ALIGN="left">&#9746;</TD>
<TD ALIGN="left" VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman; " ALIGN="left">Definitive additional materials </P></TD></TR></TABLE>
<P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%" VALIGN="top" ALIGN="left">&#9744;</TD>
<TD ALIGN="left" VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman; " ALIGN="left">Soliciting material pursuant to Rule <FONT STYLE="white-space:nowrap">14a-12</FONT> </P></TD></TR></TABLE>
<P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><center> <P STYLE="line-height:6.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1.00pt solid #000000;width:21%">&nbsp;</P></center>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:24pt; font-family:Times New Roman" ALIGN="center"><B>Aon plc </B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>(Name of
Registrant as Specified in Its Charter) </B></P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">(Name of Person(s) Filing Proxy Statement, if other than the Registrant) </P>
<P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><center> <P STYLE="line-height:6.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1.00pt solid #000000;width:21%">&nbsp;</P></center>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Payment of filing fee (Check the appropriate box): </P> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%" VALIGN="top" ALIGN="left">&#9746;</TD>
<TD ALIGN="left" VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman; " ALIGN="left">No fee required. </P></TD></TR></TABLE> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%" VALIGN="top" ALIGN="left">&#9744;</TD>
<TD ALIGN="left" VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman; " ALIGN="left">Fee computed on table below per Exchange Act Rules <FONT STYLE="white-space:nowrap">14a-6(i)(1)</FONT> and <FONT
STYLE="white-space:nowrap">0-11.</FONT> </P></TD></TR></TABLE> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%">&nbsp;</TD>
<TD WIDTH="4%" VALIGN="top" ALIGN="left">(1)</TD>
<TD ALIGN="left" VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman; " ALIGN="left">Title of each class of securities to which transaction applies: </P></TD></TR></TABLE>
<P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="line-height:3.0pt;margin-top:0pt;margin-bottom:2pt;margin-left:7%;border-bottom:1px solid #000000">&nbsp;</P>
<P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%">&nbsp;</TD>
<TD WIDTH="4%" VALIGN="top" ALIGN="left">(2)</TD>
<TD ALIGN="left" VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman; " ALIGN="left">Aggregate number of securities to which transaction applies: </P></TD></TR></TABLE>
<P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="line-height:3.0pt;margin-top:0pt;margin-bottom:2pt;margin-left:7%;border-bottom:1px solid #000000">&nbsp;</P>
<P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%">&nbsp;</TD>
<TD WIDTH="4%" VALIGN="top" ALIGN="left">(3)</TD>
<TD ALIGN="left" VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman; " ALIGN="left">Per unit price or other underlying value of transaction computed pursuant to Exchange Act Rule <FONT
STYLE="white-space:nowrap">0-11</FONT> (set forth the amount on which the filing fee is calculated and state how it was determined): </P></TD></TR></TABLE> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<P STYLE="line-height:3.0pt;margin-top:0pt;margin-bottom:2pt;margin-left:7%;border-bottom:1px solid #000000">&nbsp;</P> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%">&nbsp;</TD>
<TD WIDTH="4%" VALIGN="top" ALIGN="left">(4)</TD>
<TD ALIGN="left" VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman; " ALIGN="left">Proposed maximum aggregate value of transaction: </P></TD></TR></TABLE>
<P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="line-height:3.0pt;margin-top:0pt;margin-bottom:2pt;margin-left:7%;border-bottom:1px solid #000000">&nbsp;</P>
<P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%">&nbsp;</TD>
<TD WIDTH="4%" VALIGN="top" ALIGN="left">(5)</TD>
<TD ALIGN="left" VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman; " ALIGN="left">Total fee paid: </P></TD></TR></TABLE> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<P STYLE="line-height:3.0pt;margin-top:0pt;margin-bottom:2pt;margin-left:7%;border-bottom:1px solid #000000">&nbsp;</P> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%" VALIGN="top" ALIGN="left">&#9744;</TD>
<TD ALIGN="left" VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman; " ALIGN="left">Fee paid previously with preliminary materials. </P></TD></TR></TABLE>
<P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%" VALIGN="top" ALIGN="left">&#9744;</TD>
<TD ALIGN="left" VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman; " ALIGN="left">Check box if any part of the fee is offset as provided by Exchange Act Rule
<FONT STYLE="white-space:nowrap">0-11(a)(2)</FONT> and identify the filing for which the offsetting fee was paid previously. Identify the previous filing by registration statement number, or the form or schedule and the date of its filing.
</P></TD></TR></TABLE> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%">&nbsp;</TD>
<TD WIDTH="4%" VALIGN="top" ALIGN="left">(1)</TD>
<TD ALIGN="left" VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman; " ALIGN="left">Amount previously paid: </P></TD></TR></TABLE>
<P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="line-height:3.0pt;margin-top:0pt;margin-bottom:2pt;margin-left:7%;border-bottom:1px solid #000000">&nbsp;</P>
<P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%">&nbsp;</TD>
<TD WIDTH="4%" VALIGN="top" ALIGN="left">(2)</TD>
<TD ALIGN="left" VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman; " ALIGN="left">Form, schedule or registration statement no.: </P></TD></TR></TABLE>
<P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="line-height:3.0pt;margin-top:0pt;margin-bottom:2pt;margin-left:7%;border-bottom:1px solid #000000">&nbsp;</P>
<P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%">&nbsp;</TD>
<TD WIDTH="4%" VALIGN="top" ALIGN="left">(3)</TD>
<TD ALIGN="left" VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman; " ALIGN="left">Filing party: </P></TD></TR></TABLE> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<P STYLE="line-height:3.0pt;margin-top:0pt;margin-bottom:2pt;margin-left:7%;border-bottom:1px solid #000000">&nbsp;</P> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%">&nbsp;</TD>
<TD WIDTH="4%" VALIGN="top" ALIGN="left">(4)</TD>
<TD ALIGN="left" VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman; " ALIGN="left">Date filed: </P></TD></TR></TABLE> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<P STYLE="line-height:3.0pt;margin-top:0pt;margin-bottom:2pt;margin-left:7%;border-bottom:1px solid #000000">&nbsp;</P> <P STYLE="font-size:10pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<P STYLE="line-height:1.0pt;margin-top:0pt;margin-bottom:0pt;border-bottom:1px solid #000000">&nbsp;</P> <P STYLE="line-height:3.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1px solid #000000">&nbsp;</P>
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 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>SUPPLEMENT TO PROXY STATEMENT </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>For </B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>THE 2019 ANNUAL
GENERAL MEETING OF SHAREHOLDERS </B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>To Be Held On Friday, June&nbsp;21, 2019 </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">This supplement, dated May&nbsp;21, 2019 (this &#147;Supplement&#148;), supplements the definitive proxy statement (the &#147;Proxy
Statement&#148;) filed by Aon plc (the &#147;Company&#148;) with the U.S. Securities and Exchange Commission (the &#147;SEC&#148;) on April&nbsp;26, 2019 and made available to the Company&#146;s shareholders in connection with the solicitation of
proxies by the Board of Directors of the Company (the &#147;Board&#148;) for the 2019 Annual General Meeting of Shareholders (the &#147;Annual Meeting&#148;), scheduled to be held on Friday, June&nbsp;21, 2019, at 8:00 a.m. British Summer Time. This
Supplement is being filed with the SEC and made available to shareholders on or about May&nbsp;21, 2019. Holders of the Company&#146;s Class&nbsp;A Ordinary Shares at the close of business on April&nbsp;26, 2019 are entitled to vote at the Annual
Meeting. </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">The Proxy Statement included an Equity Compensation Plan Information table (the &#147;Plan Information&#148;) on page 85 that
summarized the number of Class&nbsp;A Ordinary Shares that may be issued under the Company&#146;s equity compensation plans as of December&nbsp;31, 2018. The table set forth below updates the Plan Information to present the number of Class&nbsp;A
Ordinary Shares that may be issued under the Company&#146;s equity compensation plans as of March&nbsp;31, 2019. As of March&nbsp;31, 2019, the Company had 3,800,678 shares available for issuance under the Amended and Restated Aon plc 2011 Incentive
Plan. </P> <P STYLE="margin-top:18pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><B>Equity Compensation Plan Information </B></P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">The
following table summarizes the number of Class&nbsp;A Ordinary Shares that may be issued under our equity compensation plans as of March&nbsp;31, 2019. </P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%" BORDER="0" STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" ALIGN="center">


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<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:8pt">
<TD VALIGN="bottom" NOWRAP> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; border-bottom:1.00pt solid #000000; display:table-cell; font-size:8pt; font-family:Times New Roman; "><B>Plan Category</B></P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom" COLSPAN="2" ALIGN="center" STYLE="border-bottom:1.00pt solid #000000"><B>Number&nbsp;of&nbsp;securities&nbsp;to<BR>be issued upon exercise<BR>of outstanding options,<BR>warrants and rights</B><br><B>(a)</B></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" COLSPAN="2" ALIGN="center" STYLE="border-bottom:1.00pt solid #000000"><B>Weighted&nbsp;average<BR>exercise price of<BR>outstanding<BR>options, warrants<BR>and rights</B><br><B>(b)</B></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" COLSPAN="2" ALIGN="center" STYLE="border-bottom:1.00pt solid #000000"><B>Number&nbsp;of&nbsp;securities<BR>remaining&nbsp;available&nbsp;for<BR>future issuance under<BR>equity compensation<BR>plans (excluding<BR>securities
reflected in<BR>column&nbsp;(a))</B><br><B>(c)</B></TD>
<TD VALIGN="bottom">&nbsp;</TD></TR>


<TR BGCOLOR="#cceeff" STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; margin-left:1.00em; text-indent:-1.00em; font-size:10pt; font-family:Times New Roman">Equity compensation plans approved by security holders</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD NOWRAP VALIGN="top">&nbsp;</TD>
<TD NOWRAP VALIGN="top" ALIGN="right">7,150,590</TD>
<TD NOWRAP VALIGN="top"><SUP STYLE="font-size:85%; vertical-align:top">(1)(2)</SUP>&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD NOWRAP VALIGN="top">&nbsp;</TD>
<TD NOWRAP VALIGN="top" ALIGN="right">43.20</TD>
<TD NOWRAP VALIGN="top"><SUP STYLE="font-size:85%; vertical-align:top">(3)</SUP>&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD NOWRAP VALIGN="top">&nbsp;</TD>
<TD NOWRAP VALIGN="top" ALIGN="right">7,112,168</TD>
<TD NOWRAP VALIGN="top"><SUP STYLE="font-size:85%; vertical-align:top">(4)</SUP>&nbsp;</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; margin-left:1.00em; text-indent:-1.00em; font-size:10pt; font-family:Times New Roman">Equity compensation plans not approved by security holders<SUP
STYLE="font-size:85%; vertical-align:top">(5) </SUP></P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="right">418,085</TD>
<TD NOWRAP VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="right">&#151;</TD>
<TD NOWRAP VALIGN="bottom"><SUP STYLE="font-size:85%; vertical-align:top">(6) </SUP>&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="right">&#151;</TD>
<TD NOWRAP VALIGN="bottom"><SUP STYLE="font-size:85%; vertical-align:top">(7) </SUP>&nbsp;</TD></TR>
<TR STYLE="font-size:1px; ">
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; border-top:1.00px solid #000000">&nbsp;</P></TD>
<TD VALIGN="bottom"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; border-top:1.00px solid #000000">&nbsp;</P></TD>
<TD>&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; border-top:1.00px solid #000000">&nbsp;</P></TD>
<TD VALIGN="bottom"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; border-top:1.00px solid #000000">&nbsp;</P></TD>
<TD>&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; border-top:1.00px solid #000000">&nbsp;</P></TD>
<TD VALIGN="bottom"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; border-top:1.00px solid #000000">&nbsp;</P></TD>
<TD>&nbsp;</TD></TR>
<TR BGCOLOR="#cceeff" STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" STYLE="BORDER-BOTTOM:1px solid #000000"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; margin-left:1.00em; text-indent:-1.00em; font-size:10pt; font-family:Times New Roman">Total</P></TD>
<TD VALIGN="bottom" STYLE=" BORDER-BOTTOM:1px solid #000000">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom" STYLE="BORDER-BOTTOM:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" STYLE="BORDER-BOTTOM:1px solid #000000" ALIGN="right">7,568,675</TD>
<TD NOWRAP VALIGN="bottom" STYLE="BORDER-BOTTOM:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" STYLE=" BORDER-BOTTOM:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" STYLE="BORDER-BOTTOM:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" STYLE="BORDER-BOTTOM:1px solid #000000" ALIGN="right">43.20</TD>
<TD NOWRAP VALIGN="bottom" STYLE="BORDER-BOTTOM:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" STYLE=" BORDER-BOTTOM:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" STYLE="BORDER-BOTTOM:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" STYLE="BORDER-BOTTOM:1px solid #000000" ALIGN="right">7,112,168</TD>
<TD NOWRAP VALIGN="bottom" STYLE="BORDER-BOTTOM:1px solid #000000">&nbsp;</TD></TR>
</TABLE> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%" VALIGN="top" ALIGN="left">(1)</TD>
<TD ALIGN="left" VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman; " ALIGN="left">This amount includes the following: </P></TD></TR></TABLE>
<P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%">&nbsp;</TD>
<TD WIDTH="4%" VALIGN="top" ALIGN="left">&#150;</TD>
<TD ALIGN="left" VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman; " ALIGN="left">180,000 shares that may be issued in connection with outstanding share options under the 2001 Aon Stock
Incentive Plan </P></TD></TR></TABLE> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%">&nbsp;</TD>
<TD WIDTH="4%" VALIGN="top" ALIGN="left">&#150;</TD>
<TD ALIGN="left" VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman; " ALIGN="left">3,993,852 shares that may be issued in connection with share awards; </P></TD></TR></TABLE>
<P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%">&nbsp;</TD>
<TD WIDTH="4%" VALIGN="top" ALIGN="left">&#150;</TD>
<TD ALIGN="left" VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman; " ALIGN="left">12,657 shares that may be used in connection with share awards under the 2001 Aon Stock Incentive Plan;
</P></TD></TR></TABLE>
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<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%">&nbsp;</TD>
<TD WIDTH="4%" VALIGN="top" ALIGN="left">&#150;</TD>
<TD ALIGN="left" VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman; " ALIGN="left">118,301 shares that may be issued in connection with deferred share awards under the 2001 Aon Stock Incentive
Plan; </P></TD></TR></TABLE> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%">&nbsp;</TD>
<TD WIDTH="4%" VALIGN="top" ALIGN="left">&#150;</TD>
<TD ALIGN="left" VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman; " ALIGN="left">144,000 shares that may be issued in connection with the US employee share purchase plan;
</P></TD></TR></TABLE> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%">&nbsp;</TD>
<TD WIDTH="4%" VALIGN="top" ALIGN="left">&#150;</TD>
<TD ALIGN="left" VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman; " ALIGN="left">256,843 shares that may be issued in connection with the UK ShareSave share plan; </P></TD></TR></TABLE>
<P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%">&nbsp;</TD>
<TD WIDTH="4%" VALIGN="top" ALIGN="left">&#150;</TD>
<TD ALIGN="left" VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman; " ALIGN="left">70,036 shares that may be issued to satisfy obligations under the Aon Deferred Compensation Plan in connection
with the 2001 Aon Stock Incentive Plan; and </P></TD></TR></TABLE> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%">&nbsp;</TD>
<TD WIDTH="4%" VALIGN="top" ALIGN="left">&#150;</TD>
<TD ALIGN="left" VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman; " ALIGN="left">2,374,901 shares that may be issued in connection with the settlement of performance share units. For awards
where the performance period has been completed, the actual number of shares to be issued is shown. For awards tracking significantly below threshold, the threshold number of shares which may be issued is shown. For all other performance share
awards, the maximum number of shares which may be issued is shown. </P></TD></TR></TABLE> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%" VALIGN="top" ALIGN="left">(2)</TD>
<TD ALIGN="left" VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman; " ALIGN="left">On November&nbsp;1, 2002, the Aon Deferred Compensation Plan was amended to discontinue the distribution of
shares with respect to deferrals after November&nbsp;1, 2002 from that plan. As of March&nbsp;31, 2019, based on a share price of $170.70, the maximum number of shares that could be issued under the Aon Deferred Compensation Plan was 70,036.
</P></TD></TR></TABLE> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%" VALIGN="top" ALIGN="left">(3)</TD>
<TD ALIGN="left" VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman; " ALIGN="left">Indicates weighted average exercise price of 180,000 outstanding options under the 2001 Aon Stock Incentive
Plan. </P></TD></TR></TABLE> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%" VALIGN="top" ALIGN="left">(4)</TD>
<TD ALIGN="left" VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman; " ALIGN="left">The total number of Class&nbsp;A Ordinary Shares authorized for issuance in connection with awards under the
Amended and Restated Aon plc 2011 Incentive Plan, as amended, is 34,000,000. As of March&nbsp;31, 2019, 3,800,678 shares remained available for future issuance under this plan. The amount shown in column (c)&nbsp;also includes 3,311,490 shares
available for future issuance under the Aon plc Global Share Purchase Plan. Permissible awards under the Shareholder-Approved Plan include share options, share appreciation rights, restricted shares, restricted share units and other <FONT
STYLE="white-space:nowrap">share-based</FONT> awards, including awards where the vesting, granting or settlement of which is contingent upon the achievement of specified performance goals, called &#147;performance awards.&#148;
</P></TD></TR></TABLE> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%" VALIGN="top" ALIGN="left">(5)</TD>
<TD ALIGN="left" VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman; " ALIGN="left">Below are the material features of our equity compensation plans that have not been approved by shareholders:
</P></TD></TR></TABLE> <P STYLE="margin-top:6pt; margin-bottom:0pt; margin-left:4%; font-size:10pt; font-family:Times New Roman"><B>Aon Supplemental Savings Plan </B></P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; margin-left:4%; font-size:10pt; font-family:Times New Roman">The Supplemental Savings Plan was adopted by the Board of Directors of Aon Corporation in 1998. It is a nonqualified supplemental retirement
plan that provides benefits to participants in the Aon Savings Plan whose employer matching contributions are limited because of <FONT STYLE="white-space:nowrap">IRS-imposed</FONT> restrictions. Prior to January&nbsp;1, 2004, participants covered
under the Supplemental Plan were credited with an additional matching allocation they would have received under the former Aon Savings Plan provisions&#151;100% of the first 1% to 3% of compensation (&#147;Tier&nbsp;I&#148;) and 75% of the next 4%
to 6% of compensation (&#147;Tier&nbsp;2&#148;)&#151;had compensation up to $500,000 been considered. Between January&nbsp;1, 2004 and December&nbsp;31, 2005, only participants defined as employees of Aon Consulting&#146;s Human Resource Outsourcing
Group maintained the matching provision in the Supplemental Plan. Participants may elect to have Tier&nbsp;I allocations credited to their accounts as if invested in a money market account or as if invested in Class&nbsp;A Ordinary Shares.
Tier&nbsp;I allocations directed to a Class&nbsp;A Ordinary Shares account may not be moved to the money market account, regardless of the participant&#146;s age. As of January&nbsp;1, 2006, no participants are eligible for Tier&nbsp;I or
Tier&nbsp;II matching allocations. Before the beginning of each plan year, an election may be made by any participant to transfer some or all of a participant&#146;s money market account to the Class&nbsp;A Ordinary Shares account. All amounts
credited to the Class&nbsp;A Ordinary Shares account are credited with dividends and other investment returns as under the Aon Savings Plan fund. Between January&nbsp;1, 2004 and December&nbsp;31, 2008, the Supplemental Plan provision in effect
provided employees hired January&nbsp;1, 2004 and later, benefits on plan compensation above the IRS limits (and up to $500,000) as under the Aon Retirement Account (the &#147;ARA&#148;) provision of the Aon
</P>
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 <P STYLE="margin-top:0pt; margin-bottom:0pt; margin-left:4%; font-size:10pt; font-family:Times New Roman">
Savings Plan. Benefits were in the form of a discretionary <FONT STYLE="white-space:nowrap">non-contributory</FONT> company contribution made to eligible employees active at the end of the plan
year with 1,000 or more hours of paid service. The Supplemental Plan ARA allocation was calculated using the same formula that the Board determines for the Aon Savings Plan ARA. Ongoing balances which resulted from the Supplemental Plan ARA
allocation will continue to track the same investment options as selected by the participant under the Aon Savings Plan. This includes the Aon Class&nbsp;A Ordinary Shares option, and, like the Aon Savings Plan provision, has no transfer
restrictions. </P> <P STYLE="margin-top:6pt; margin-bottom:0pt; margin-left:4%; font-size:10pt; font-family:Times New Roman">Effective for plan years beginning January&nbsp;1, 2009, a new Supplemental Plan provision went into effect whereby
employees were credited with an additional matching allocation they would have received under the new Aon Savings Plan match provision&#151;100% of the first 6% of compensation&#151;had compensation up to $500,000 been considered. Participants must
also contribute the limit prescribed by the IRS ($19,000 for 2019) and be active on the last day of the year in order to receive the allocation. As of March&nbsp;31, 2019, the number of shares that could be issued under the plan was 278,345. </P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; margin-left:4%; font-size:10pt; font-family:Times New Roman"><B>Aon Supplemental Employee Stock Ownership Plan </B></P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; margin-left:4%; font-size:10pt; font-family:Times New Roman">The Aon Supplemental Employee Stock Ownership Plan was a plan established in 1989 as a nonqualified supplemental retirement plan that provided
benefits to participants in the Aon Employee Stock Ownership Plan whose employer contributions were limited because of <FONT STYLE="white-space:nowrap">IRS-imposed</FONT> restrictions. As of 1998, no additional amounts have been credited to
participant accounts, although account balances are maintained for participants, and credited with dividends, until distribution is required under the plan. Distributions are made solely in Class&nbsp;A Ordinary Shares. No specific authorization of
Class&nbsp;A Ordinary Shares for the plan has been made. As of March&nbsp;31, 2019, the number of shares that could be issued under the plan was 139,740. </P> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%" VALIGN="top" ALIGN="left">(6)</TD>
<TD ALIGN="left" VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman; " ALIGN="left">The <FONT STYLE="white-space:nowrap">weighted-average</FONT> exercise price of such shares is uncertain and is
not included in this column. </P></TD></TR></TABLE> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%" VALIGN="top" ALIGN="left">(7)</TD>
<TD ALIGN="left" VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman; " ALIGN="left">None of these equity compensation plans contain a limit on the number of shares that may be issued under such
plans; however, these plans are subject to the limitations set forth in the descriptions of these plans contained in Note 5 above. </P></TD></TR></TABLE>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">Additionally, the New York Stock Exchange (the &#147;NYSE&#148;) has informed the Company that it has determined that Proposal 10 is a
&#147;routine&#148; matter. Accordingly, the question titled &#147;What proposals are considered &#145;routine&#146; or <FONT STYLE="white-space:nowrap">&#145;non-routine&#146;?&#148;</FONT> on page 92 of the Proxy Statement under the heading
&#147;Questions and Answers About the 2019 Annual General Meeting and Voting&#148; is hereby revised in its entirety to read as follows: </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">&#147;What
proposals are considered &#147;routine&#148; or <FONT STYLE="white-space:nowrap">&#147;non-routine&#148;?</FONT> </P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Proposals 4, 5, 6, 7, 9, 10, 11, 12, 13,
and 14 (the receipt of Aon&#146;s Annual Report, ratification of the appointment of Ernst&nbsp;&amp; Young US as Aon&#146;s independent registered public accounting firm for 2019, appointment of Ernst&nbsp;&amp; Young UK as Aon&#146;s statutory
auditor, authorizing the Board to determine Ernst&nbsp;&amp; Young UK&#146;s remuneration, the approval of the Capital Reduction, the adoption of the New Articles, the approval of the form of share repurchase contracts and repurchase counterparties,
the authorization of our directors to allot equity securities, the authorization of our directors to allot equity securities free from <FONT STYLE="white-space:nowrap">pre-emption</FONT> rights, and the authorization of the Company to make political
donations and expenditures) are each considered a routine matter under the rules of the NYSE. A broker, bank, or other nominee may generally vote on routine matters, and therefore no broker <FONT STYLE="white-space:nowrap">non-votes</FONT> are
expected to occur in connection with Proposals 4, 5, 6, 7, 9, 10, 11, 12, 13, and 14. </P>
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 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Proposals 1, 2, 3, and 8 (the <FONT STYLE="white-space:nowrap">re-election</FONT> of directors by way of
separate ordinary resolutions, the advisory vote on executive compensation, the advisory vote on the directors&#146; remuneration report, and the approval of the amended and restated Shareholder-Approved Plan) are matters considered <FONT
STYLE="white-space:nowrap">non-routine</FONT> under the rules of the NYSE. A broker, bank, or other nominee may not vote on these <FONT STYLE="white-space:nowrap">non-routine</FONT> matters without specific voting instructions from the beneficial
owner. As a result, there may be broker <FONT STYLE="white-space:nowrap">non-votes</FONT> with respect to Proposals 1, 2, 3, and 8.&#148; </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">Except as described in this Supplement, none of the items or information presented in the Proxy Statement is affected by this
Supplement.&nbsp;This Supplement does not provide all of the information that is important to your voting decisions at the Annual Meeting. The Proxy Statement contains other important additional information. We encourage you to carefully read this
Supplement together with the Proxy Statement. </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">If you have already returned your proxy or voting instruction card or provided voting
instructions, you do not need to take any action unless you wish to change your vote.</P>
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