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      id="Fact000014">&lt;p id="xdx_A87_eoef--SupplementToProspectusTextBlock_za2HhEaaExbj" style="font: 11pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;THE RBB FUND, INC.&lt;/b&gt;&lt;/p&gt;

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&lt;p style="font: 11pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;EMERALD BANKING &amp;amp; FINANCE EVOLUTION FUND&lt;/b&gt;&lt;/p&gt;

&lt;p style="font: 11pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;EMERALD GROWTH FUND&lt;/b&gt;&lt;/p&gt;

&lt;p style="font: 11pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;&#160;&lt;/b&gt;&lt;/p&gt;

&lt;p style="font: 11pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;&lt;/b&gt;&lt;/p&gt;

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&lt;p style="font: 11pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;&#160;&lt;/b&gt;&lt;/p&gt;

&lt;p style="font: 11pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Supplement dated July 10, 2026&lt;/b&gt;&lt;/p&gt;

&lt;p style="font: 11pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;to the Prospectus dated &lt;span id="xdx_90E_eoef--ProspectusDate_c20260710__20260710_zRIk0eMNTdyg"&gt;July 18, 2025&lt;/span&gt;, as supplemented&lt;/b&gt;&lt;/p&gt;

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&lt;p style="font: 11pt Times New Roman, Times, Serif; margin: 0"&gt;&lt;b&gt;&lt;/b&gt;&lt;/p&gt;

&lt;div style="margin: 3pt auto; width: 50%"&gt;&lt;div style="border-top: Black 1pt solid; font-size: 1pt"&gt;&#160;&lt;/div&gt;&lt;/div&gt;

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&lt;p style="font: 11pt Times New Roman, Times, Serif; margin: 0"&gt;&#160;&lt;/p&gt;

&lt;p style="font: 11pt Times New Roman, Times, Serif; margin: 0"&gt;&lt;i&gt;This supplement serves as notification of the following changes, effective
immediately:&lt;/i&gt;&lt;/p&gt;

&lt;p style="font: 11pt Times New Roman, Times, Serif; margin: 0"&gt;&#160;&lt;/p&gt;



&lt;table cellpadding="0" cellspacing="0" style="font: 11pt Times New Roman, Times, Serif; margin-top: 0; margin-bottom: 0pt; width: 100%"&gt;&lt;tr style="vertical-align: top; text-align: justify"&gt;
&lt;td style="width: 0in"&gt;&lt;/td&gt;&lt;td style="width: 0.5in; text-align: left"&gt;&lt;b&gt;1.&lt;/b&gt;&lt;/td&gt;&lt;td style="text-align: justify"&gt;&lt;b&gt;NEW WEBSITE&lt;/b&gt;&lt;/td&gt;
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&lt;p style="font: 11pt Times New Roman, Times, Serif; margin: 0 0 0 0.5in; text-align: justify"&gt;Information regarding the Emerald Growth
Fund, including the Prospectus, SAI, reports to shareholders, and other information, is available at &lt;span id="xdx_900_eoef--PerformanceAvailabilityWebSiteAddress_c20260710__20260710__dei--LegalEntityAxis__custom--S000093696Member_zL08fdxdWqW"&gt;www.teamemeraldfunds.com&lt;/span&gt;. Accordingly,
all references to the website for the Emerald Growth Fund should be updated accordingly.&lt;/p&gt;

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&lt;table cellpadding="0" cellspacing="0" style="font: 11pt Times New Roman, Times, Serif; margin-top: 0; margin-bottom: 0pt; width: 100%"&gt;&lt;tr style="vertical-align: top; text-align: justify"&gt;
&lt;td style="width: 0in"&gt;&lt;/td&gt;&lt;td style="width: 0.5in; text-align: left"&gt;&lt;b&gt;2.&lt;/b&gt;&lt;/td&gt;&lt;td style="text-align: justify"&gt;&lt;b&gt;CHANGE IN CLASS A SALES LOAD MINIMUM for EMERALD GROWTH FUND&lt;/b&gt;&lt;/td&gt;
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&lt;p style="font: 11pt Times New Roman, Times, Serif; margin: 0 0 0 0.5in; text-align: justify"&gt;The minimum investment amount eligible to
receive a discount to purchase Class A Shares of the Emerald Growth Fund has been reduced from $100,000 to $50,000. Accordingly, the paragraph
in the Prospectus entitled &#x201c;Summary Section &#x2013; Emerald Growth Fund &#x2013; Fees and Expenses of the Fund&#x201d; is amended
and restated in its entirety as shown below:&lt;/p&gt;

&lt;p style="font: 11pt Times New Roman, Times, Serif; margin: 0 0 0 0.5in; text-align: justify"&gt;&lt;/p&gt;

&lt;p style="font: 11pt Times New Roman, Times, Serif; margin: 0 0 0 0.5in; text-align: justify"&gt;&#160;&lt;/p&gt;

&lt;p id="xdx_988_eoef--ExpenseExampleNarrativeTextBlock_c20260710__20260710__dei--LegalEntityAxis__custom--S000093696Member_zrGXJDjQkimk" style="font: 11pt Times New Roman, Times, Serif; margin: 0 0 0 0.5in; text-align: justify"&gt;This
table describes the fees and expenses that you may pay if you buy, hold, and sell shares of the Fund. &lt;b&gt;You may pay other fees, such
as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below.&lt;/b&gt; &lt;span id="xdx_909_eoef--ExpenseBreakpointDiscounts_c20260710__20260710__dei--LegalEntityAxis__custom--S000093696Member_zIRNvnZtE6Vi"&gt;You
may qualify for certain sales charge discounts if you and your family invest, or agree to invest in the future, at least &lt;span id="xdx_909_eoef--ExpenseBreakpointMinimumInvestmentRequiredAmount_c20260710__20260710__dei--LegalEntityAxis__custom--S000093696Member_zI1I47DO7Izb"&gt;$50,000&lt;/span&gt; in the
Fund.&lt;/span&gt; More information about these and other discounts is available from your financial intermediary, in the section &#x201c;SHAREHOLDER
INFORMATION&#x201d; starting from page 23 of the Prospectus and the section &#x201c;PURCHASE AND REDEMPTION INFORMATION&#x201d; starting
from page 38 of the Fund&#x2019;s statement of additional information (the &#x201c;SAI&#x201d;). In addition, please see Appendix A - Intermediary
Sales Charge Waivers and Discounts.&lt;/p&gt;



&lt;p style="font: 11pt Times New Roman, Times, Serif; margin: 0"&gt;&lt;b&gt;&#160;&lt;/b&gt;&lt;/p&gt;

&lt;p style="font: 11pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;* * * * *&lt;/b&gt;&lt;/p&gt;

&lt;p style="font: 11pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;&#160;&lt;/b&gt;&lt;/p&gt;

&lt;p style="font: 11pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Please retain this supplement for your reference.&lt;/b&gt;&lt;/p&gt;

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    <oef:ProspectusDate contextRef="AsOf2026-07-10" id="Fact000015">2025-07-18</oef:ProspectusDate>
    <oef:PerformanceAvailabilityWebSiteAddress
      contextRef="From2026-07-102026-07-10_custom_S000093696Member"
      id="Fact000016">www.teamemeraldfunds.com</oef:PerformanceAvailabilityWebSiteAddress>
    <oef:ExpenseExampleNarrativeTextBlock
      contextRef="From2026-07-102026-07-10_custom_S000093696Member"
      id="Fact000017">This
table describes the fees and expenses that you may pay if you buy, hold, and sell shares of the Fund. &lt;b&gt;You may pay other fees, such
as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below.&lt;/b&gt; &lt;span id="xdx_909_eoef--ExpenseBreakpointDiscounts_c20260710__20260710__dei--LegalEntityAxis__custom--S000093696Member_zIRNvnZtE6Vi"&gt;You
may qualify for certain sales charge discounts if you and your family invest, or agree to invest in the future, at least &lt;span id="xdx_909_eoef--ExpenseBreakpointMinimumInvestmentRequiredAmount_c20260710__20260710__dei--LegalEntityAxis__custom--S000093696Member_zI1I47DO7Izb"&gt;$50,000&lt;/span&gt; in the
Fund.&lt;/span&gt; More information about these and other discounts is available from your financial intermediary, in the section &#x201c;SHAREHOLDER
INFORMATION&#x201d; starting from page 23 of the Prospectus and the section &#x201c;PURCHASE AND REDEMPTION INFORMATION&#x201d; starting
from page 38 of the Fund&#x2019;s statement of additional information (the &#x201c;SAI&#x201d;). In addition, please see Appendix A - Intermediary
Sales Charge Waivers and Discounts.</oef:ExpenseExampleNarrativeTextBlock>
    <oef:ExpenseBreakpointDiscounts
      contextRef="From2026-07-102026-07-10_custom_S000093696Member"
      id="Fact000018">You
may qualify for certain sales charge discounts if you and your family invest, or agree to invest in the future, at least $50,000 in the
Fund.</oef:ExpenseBreakpointDiscounts>
    <oef:ExpenseBreakpointMinimumInvestmentRequiredAmount
      contextRef="From2026-07-102026-07-10_custom_S000093696Member"
      decimals="0"
      id="Fact000019"
      unitRef="USD">50000</oef:ExpenseBreakpointMinimumInvestmentRequiredAmount>
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