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&lt;div style="font: 10pt/normal times new roman, times, serif; margin: 0pt 0px; text-align: center; font-size-adjust: none; font-stretch: normal;"&gt;&lt;b&gt;&lt;/b&gt;&lt;/div&gt;
&lt;p style="font: 10pt/normal times new roman, times, serif; margin: 0pt 0px; text-align: center; font-size-adjust: none; font-stretch: normal;"&gt;Supplement dated January 15, 2013 (&amp;#8220;Supplement&amp;#8221;)&lt;/p&gt;
&lt;p style="font: 10pt/normal times new roman, times, serif; margin: 0pt 0px; text-align: center; font-size-adjust: none; font-stretch: normal;"&gt;to the following Prospectuses, Summary Prospectuses and Statement of Additional Information&lt;/p&gt;
&lt;p style="font: 10pt/normal times new roman, times, serif; margin: 0pt 0px; text-align: center; font-size-adjust: none; font-stretch: normal;"&gt;&amp;#160;&lt;/p&gt;
&lt;p style="font: 10pt/normal times new roman, times, serif; text-align: center; margin-top: 0pt; margin-bottom: 0pt; font-size-adjust: none; font-stretch: normal;"&gt;&lt;b&gt;MainStay 130/30 Core Fund&lt;/b&gt;&lt;/p&gt;
&lt;p style="font: 10pt/normal times new roman, times, serif; margin: 0pt 0px; text-align: center; font-size-adjust: none; font-stretch: normal;"&gt;&lt;b&gt;MainStay 130/30 International Fund&lt;/b&gt;&lt;/p&gt;
&lt;p style="font: 10pt/normal times new roman, times, serif; margin: 0pt 0px; text-align: center; font-size-adjust: none; font-stretch: normal;"&gt;&lt;b&gt;MainStay Common Stock Fund&lt;/b&gt;&lt;/p&gt;
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&lt;p style="font: 10pt/normal times new roman, times, serif; margin: 0pt 0px; text-align: center; font-size-adjust: none; font-stretch: normal;"&gt;&lt;b&gt;MainStay S&amp;amp;P 500 Index Fund&lt;/b&gt;&lt;/p&gt;
&lt;p style="font: 10pt/normal times new roman, times, serif; margin: 0pt 0px; text-align: center; font-size-adjust: none; font-stretch: normal;"&gt;Summary Prospectuses and Prospectus, each dated February 28, 2012, as supplemented, and&lt;/p&gt;
&lt;p style="font: 10pt/normal times new roman, times, serif; margin: 0pt 0px; text-align: center; font-size-adjust: none; font-stretch: normal;"&gt;Statement of Additional Information, dated February 28, 2012, as amended December 17, 2012,&lt;/p&gt;
&lt;p style="font: 10pt/normal times new roman, times, serif; margin: 0pt 0px; text-align: center; font-size-adjust: none; font-stretch: normal;"&gt;and as supplemented&lt;/p&gt;
&lt;p style="font: 10pt/normal times new roman, times, serif; margin: 0pt 0px; text-align: center; font-size-adjust: none; font-stretch: normal;"&gt;&amp;#160;&lt;/p&gt;
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&lt;p style="font: 10pt/normal times new roman, times, serif; margin: 0pt 0px; text-align: center; font-size-adjust: none; font-stretch: normal;"&gt;Summary Prospectus and Prospectus, each dated May 25, 2012, as supplemented, and&lt;/p&gt;
&lt;p style="font: 10pt/normal times new roman, times, serif; margin: 0pt 0px; text-align: center; font-size-adjust: none; font-stretch: normal;"&gt;Statement of Additional Information, dated February 28, 2012, as amended December 17, 2012,&lt;/p&gt;
&lt;p style="font: 10pt/normal times new roman, times, serif; margin: 0pt 0px; text-align: center; font-size-adjust: none; font-stretch: normal;"&gt;and as supplemented&lt;/p&gt;
&lt;p style="font: 10pt/normal times new roman, times, serif; margin: 0pt 0px; text-align: center; font-size-adjust: none; font-stretch: normal;"&gt;&amp;#160;&lt;/p&gt;
&lt;p style="font: 10pt/normal times new roman, times, serif; margin: 0pt 0px; text-align: justify; font-size-adjust: none; font-stretch: normal;"&gt;Effective on or about January 25, 2012, Madison Square Investors LLC (&amp;#8220;Madison Square Investors&amp;#8221;), the Subadvisor to the Funds, will change its name to Cornerstone Capital Management Holdings LLC (&amp;#8220;Cornerstone Capital Management&amp;#8221;). Accordingly, upon the effective date of Madison Square Investors&amp;#8217; name change, the Summary Prospectuses, Prospectuses, and SAI are revised to reflect that Cornerstone Capital Management is the Funds&amp;#8217; Subadvisor.&lt;/p&gt;</cik0000787441:SupplementTextBlock>

<cik0000787441:SupplementTextBlock contextRef="Context_Custom_28-Feb-2012_DocumentInformationDocumentAxis_MainstayCommonStockFundProspectusSummaryMember_LegalEntityAxis_S000006903Member">&lt;p style="font: 10pt/normal times new roman, times, serif; margin: 0pt 0px; text-align: center; font-size-adjust: none; font-stretch: normal;"&gt;&lt;b&gt;THE MAINSTAY GROUP OF FUNDS&lt;/b&gt;&lt;/p&gt;
&lt;p style="font: 10pt/normal times new roman, times, serif; margin: 0pt 0px; text-align: center; font-size-adjust: none; font-stretch: normal;"&gt;&amp;#160;&lt;/p&gt;
&lt;p style="font: 10pt/normal times new roman, times, serif; margin: 0pt 0px; text-align: center; font-size-adjust: none; font-stretch: normal;"&gt;Supplement dated January 15, 2013 (&amp;#8220;Supplement&amp;#8221;)&lt;/p&gt;
&lt;p style="font: 10pt/normal times new roman, times, serif; margin: 0pt 0px; text-align: center; font-size-adjust: none; font-stretch: normal;"&gt;to the following Prospectuses, Summary Prospectuses and Statement of Additional Information&lt;/p&gt;
&lt;p style="font: 10pt/normal times new roman, times, serif; margin: 0pt 0px; text-align: center; font-size-adjust: none; font-stretch: normal;"&gt;&amp;#160;&lt;/p&gt;
&lt;p style="font: 10pt/normal times new roman, times, serif; text-align: center; margin-top: 0pt; margin-bottom: 0pt; font-size-adjust: none; font-stretch: normal;"&gt;&lt;b&gt;MainStay 130/30 Core Fund&lt;/b&gt;&lt;/p&gt;
&lt;p style="font: 10pt/normal times new roman, times, serif; margin: 0pt 0px; text-align: center; font-size-adjust: none; font-stretch: normal;"&gt;&lt;b&gt;MainStay 130/30 International Fund&lt;/b&gt;&lt;/p&gt;
&lt;p style="font: 10pt/normal times new roman, times, serif; margin: 0pt 0px; text-align: center; font-size-adjust: none; font-stretch: normal;"&gt;&lt;b&gt;MainStay Common Stock Fund&lt;/b&gt;&lt;/p&gt;
&lt;p style="font: 10pt/normal times new roman, times, serif; margin: 0pt 0px; text-align: center; font-size-adjust: none; font-stretch: normal;"&gt;&lt;b&gt;MainStay International Equity Fund&lt;/b&gt;&lt;/p&gt;
&lt;p style="font: 10pt/normal times new roman, times, serif; margin: 0pt 0px; text-align: center; font-size-adjust: none; font-stretch: normal;"&gt;&lt;b&gt;MainStay S&amp;amp;P 500 Index Fund&lt;/b&gt;&lt;/p&gt;
&lt;p style="font: 10pt/normal times new roman, times, serif; margin: 0pt 0px; text-align: center; font-size-adjust: none; font-stretch: normal;"&gt;Summary Prospectuses and Prospectus, each dated February 28, 2012, as supplemented, and&lt;/p&gt;
&lt;p style="font: 10pt/normal times new roman, times, serif; margin: 0pt 0px; text-align: center; font-size-adjust: none; font-stretch: normal;"&gt;Statement of Additional Information, dated February 28, 2012, as amended December 17, 2012,&lt;/p&gt;
&lt;p style="font: 10pt/normal times new roman, times, serif; margin: 0pt 0px; text-align: center; font-size-adjust: none; font-stretch: normal;"&gt;and as supplemented&lt;/p&gt;
&lt;p style="font: 10pt/normal times new roman, times, serif; margin: 0pt 0px; text-align: center; font-size-adjust: none; font-stretch: normal;"&gt;&amp;#160;&lt;/p&gt;
&lt;p style="font: 10pt/normal times new roman, times, serif; margin: 0pt 0px; text-align: center; font-size-adjust: none; font-stretch: normal;"&gt;&lt;b&gt;MainStay Balanced Fund&lt;/b&gt;&lt;/p&gt;
&lt;p style="font: 10pt/normal times new roman, times, serif; margin: 0pt 0px; text-align: center; font-size-adjust: none; font-stretch: normal;"&gt;Summary Prospectus and Prospectus, each dated May 25, 2012, as supplemented, and&lt;/p&gt;
&lt;p style="font: 10pt/normal times new roman, times, serif; margin: 0pt 0px; text-align: center; font-size-adjust: none; font-stretch: normal;"&gt;Statement of Additional Information, dated February 28, 2012, as amended December 17, 2012,&lt;/p&gt;
&lt;p style="font: 10pt/normal times new roman, times, serif; margin: 0pt 0px; text-align: center; font-size-adjust: none; font-stretch: normal;"&gt;and as supplemented&lt;/p&gt;
&lt;p style="font: 10pt/normal times new roman, times, serif; margin: 0pt 0px; text-align: center; font-size-adjust: none; font-stretch: normal;"&gt;&amp;#160;&lt;/p&gt;
&lt;p style="font: 10pt/normal times new roman, times, serif; margin: 0pt 0px; text-align: center; font-size-adjust: none; font-stretch: normal;"&gt;&amp;#160;&lt;/p&gt;
&lt;p style="font: 10pt/normal times new roman, times, serif; margin: 0pt 0px; text-align: justify; font-size-adjust: none; font-stretch: normal;"&gt;Effective on or about January 25, 2012, Madison Square Investors LLC (&amp;#8220;Madison Square Investors&amp;#8221;), the Subadvisor to the Funds, will change its name to Cornerstone Capital Management Holdings LLC (&amp;#8220;Cornerstone Capital Management&amp;#8221;). Accordingly, upon the effective date of Madison Square Investors&amp;#8217; name change, the Summary Prospectuses, Prospectuses, and SAI are revised to reflect that Cornerstone Capital Management is the Funds&amp;#8217; Subadvisor.&lt;/p&gt;</cik0000787441:SupplementTextBlock>

<rr:RiskReturnHeading contextRef="Context_Custom_28-Feb-2012_DocumentInformationDocumentAxis_MainstayInternationalEquityFundProspectusSummaryMember_LegalEntityAxis_S000006902Member">&lt;div&gt;
&lt;p style="margin: 0in 0in 5.45pt; line-height: normal;" class="msonormal"&gt;&lt;font size="2" style="font-family:times new roman,times"&gt;&lt;b&gt;MainStay International Equity Fund&lt;/b&gt;&lt;/font&gt;&lt;/p&gt;
&lt;/div&gt;</rr:RiskReturnHeading>
<rr:RiskReturnHeading contextRef="Context_Custom_28-Feb-2012_DocumentInformationDocumentAxis_MainstayCommonStockFundProspectusSummaryMember_LegalEntityAxis_S000006903Member">&lt;div style="margin: 0in; margin-bottom: .0001pt;"&gt;&lt;font size="2" style="font-family:times new roman,times"&gt;&lt;b&gt;MainStay Common Stock Fund&lt;/b&gt;&lt;/font&gt;&lt;/div&gt;</rr:RiskReturnHeading>
<cik0000787441:SupplementClosingTextBlock contextRef="Context_Custom_28-Feb-2012_DocumentInformationDocumentAxis_MainstayInternationalEquityFundProspectusSummaryMember_LegalEntityAxis_S000006902Member">&lt;p style="text-align: center; margin: 0pt 0px; font: 10pt times new roman, times, serif;"&gt;&lt;b&gt;PLEASE RETAIN THIS SUPPLEMENT FOR YOUR FUTURE REFERENCE.&lt;/b&gt;&lt;/p&gt;</cik0000787441:SupplementClosingTextBlock>

<cik0000787441:SupplementClosingTextBlock contextRef="Context_Custom_28-Feb-2012_DocumentInformationDocumentAxis_MainstayCommonStockFundProspectusSummaryMember_LegalEntityAxis_S000006903Member">&lt;p style="text-align: center; margin: 0pt 0px; font: 10pt times new roman, times, serif;"&gt;&lt;b&gt;PLEASE RETAIN THIS SUPPLEMENT FOR YOUR FUTURE REFERENCE.&lt;/b&gt;&lt;/p&gt;</cik0000787441:SupplementClosingTextBlock>

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