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      id="t_3_571fa421_0514_f563_5cb2_2e8ac5e68c33">&lt;div style="margin-top:0pt;margin-bottom:0pt;font-size:11pt;font-family:times new roman;font-weight:bold;text-align:center;"&gt;BRIDGE BUILDER TRUST &lt;/div&gt;&lt;div style="margin-top:12pt;margin-bottom:0pt;font-size:11pt;font-family:times new roman;font-weight:bold;text-align:center;"&gt;Bridge Builder Small/Mid Cap Growth Fund (the &#x201c;Fund&#x201d;) &lt;/div&gt;&lt;div style="margin-top:12pt;margin-bottom:0pt;font-size:11pt;font-family:times new roman;font-weight:bold;text-align:center;"&gt;Supplement dated September&#160;21, 2026 &lt;/div&gt;&lt;div style="margin-top:0pt;margin-bottom:0pt;font-size:11pt;font-family:times new roman;font-weight:bold;text-align:center;"&gt;to the Summary Prospectus dated October&#160;27, 2025, &lt;/div&gt;&lt;div style="margin-top:0pt;margin-bottom:0pt;font-size:11pt;font-family:times new roman;font-weight:bold;text-align:center;"&gt;as amended and restated June&#160;18, 2026 and as supplemented, and the &lt;/div&gt;&lt;div style="margin-top:0pt;margin-bottom:0pt;font-size:11pt;font-family:times new roman;font-weight:bold;text-align:center;"&gt;Prospectus dated October&#160;27, 2025, as supplemented &lt;/div&gt;&lt;div style="margin-top:12pt;margin-bottom:0pt;font-size:11pt;font-family:times new roman;font-weight:bold;text-align:center;"&gt;This supplement provides new and additional information beyond that contained in the &lt;/div&gt;&lt;div style="margin-top:0pt;margin-bottom:0pt;font-size:11pt;font-family:times new roman;font-weight:bold;text-align:center;"&gt;Summary Prospectus and Prospectus and should be read in conjunction with the Summary Prospectus and Prospectus. &lt;/div&gt;&lt;div style="margin-top:12pt;margin-bottom:0pt;font-size:11pt;font-family:times new roman;text-align:justify;"&gt;At a meeting held on August 19&#x2011;20, 2026, the Board of Trustees of Bridge Builder Trust (the &#x201c;Trust&#x201d;), upon the recommendation of Olive Street Investment Advisers, LLC, approved certain changes to the Fund, including (i)&#160;a change to the Fund&#x2019;s name to &#x201c;Bridge Builder Mid Cap Fund,&#x201d; (ii) changes to the Fund&#x2019;s principal investment strategy pursuant to which the Fund will invest primarily in mid&#x2011;capitalization companies and no longer invest primarily in both small- and mid&#x2011;capitalization companies or follow a growth-oriented investment style, and (iii)&#160;a new 80% investment policy to invest in securities of mid&#x2011;capitalization companies (collectively, the &#x201c;Repositioning&#x201d;). The Trust provided shareholders with notice of the Repositioning, including advance notice of the Fund&#x2019;s new 80% investment policy pursuant to Rule 35d&#x2011;1 under the Investment Company Act of 1940, in a supplement dated August&#160;24, 2026 (the &#x201c;August Supplement&#x201d;). The Repositioning is expected to be completed by October&#160;28, 2026. &lt;/div&gt;&lt;div style="margin-top:12pt;margin-bottom:0pt;font-size:11pt;font-family:times new roman;text-align:justify;"&gt;In connection with the Repositioning, the Board also approved the appointment of certain new sub&#x2011;advisers and the termination of certain existing sub&#x2011;advisory agreements, as previously disclosed in the August Supplement. The Fund is now beginning to implement changes in connection with the Repositioning on a phased basis. &lt;/div&gt;&lt;div style="margin-top:12pt;margin-bottom:0pt;font-size:11pt;font-family:times new roman;text-align:justify;"&gt;The changes described in this supplement are expected to be implemented in accordance with the approximate dates set forth below: &lt;/div&gt;
&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;font-family:times new roman;font-size:11pt;border-spacing:0px;width:100%"&gt; 
&lt;tr style="page-break-inside:avoid"&gt; 
&lt;td style="width:4%;"&gt;&#160;&lt;/td&gt; 
&lt;td style="width:3%;vertical-align:top;text-align:left;"&gt;&#x2022;&lt;/td&gt; 
&lt;td style="width:1%;vertical-align:top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align:top;text-align:left;"&gt; &lt;div style="margin-top:0pt;margin-bottom:0pt;font-family:times new roman;font-size:11pt;text-align:justify;"&gt;Effective on or about September&#160;25, 2026, Eagle Asset Management, Inc. (&#x201c;Eagle&#x201d;) and Federated MDTA LLC (&#x201c;Federated MDT&#x201d;) will no longer serve as subadvisers to each of their respective allocated portions of the Fund. &lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt;&lt;div style="margin-top:12pt;margin-bottom:0pt;margin-left:7%;font-size:11pt;font-family:times new roman;text-align:justify;"&gt;Effective on or about the same date, LSV Asset Management (&#x201c;LSV&#x201d;) and Vaughan Nelson Investment Management, L.P. (&#x201c;Vaughan Nelson&#x201d;) will each begin serving as a subadviser to an allocated portion of the Fund. Accordingly, the revisions described below relating to Eagle, Federated MDT, LSV and Vaughan Nelson will become effective on or about September&#160;25, 2026. &lt;/div&gt;
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&lt;tr style="page-break-inside:avoid"&gt; 
&lt;td style="width:4%;"&gt;&#160;&lt;/td&gt; 
&lt;td style="width:3%;vertical-align:top;text-align:left;"&gt;&#x2022;&lt;/td&gt; 
&lt;td style="width:1%;vertical-align:top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align:top;text-align:left;"&gt; &lt;div style="margin-top:0pt;margin-bottom:0pt;font-family:times new roman;font-size:11pt;text-align:justify;"&gt;Effective on or about October&#160;2, 2026, Boston Partners Global Investors, Inc. (&#x201c;Boston Partners&#x201d;) will begin serving as a subadviser to an allocated portion of the Fund. Accordingly, the revisions described below relating to Boston Partners will become effective on or about October&#160;2, 2026. &lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt;&lt;div style="margin-top:0pt;margin-bottom:0pt;font-size:11pt;font-family:times new roman;text-align:justify;"&gt;Artisan Partners Limited Partnership, Driehaus Capital Management LLC, Los Angeles Capital Management LLC, Russell Investment Management, LLC and Stephens Investment Management Group, LLC will continue to serve as subadvisers to the Fund. &lt;/div&gt;&lt;div style="margin-top:12pt;margin-bottom:0pt;font-size:11pt;font-family:times new roman;text-align:justify;"&gt;Accordingly, the Summary Prospectus and Prospectus are hereby supplemented and revised as follows: &lt;/div&gt;
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&lt;td style="width:4%;vertical-align:top;text-align:left;"&gt;1.&lt;/td&gt; 
&lt;td style="vertical-align:top;text-align:left;"&gt; &lt;div style="margin-top:0pt;margin-bottom:0pt;font-size:11pt;font-family:times new roman;text-align:justify;"&gt;&lt;span style="font-style:italic"&gt;All references and information related to Eagle and Federated MDT, with respect to the Fund, are hereby deleted in their entirety.&lt;/span&gt; &lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt;
&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;font-family:times new roman;font-size:11pt;border-spacing:0px;width:100%"&gt; 
&lt;tr style="page-break-inside:avoid"&gt; 
&lt;td style="width:1%;"&gt;&#160;&lt;/td&gt; 
&lt;td style="width:4%;vertical-align:top;text-align:left;"&gt;2.&lt;/td&gt; 
&lt;td style="vertical-align:top;text-align:left;"&gt; &lt;div style="margin-top:0pt;margin-bottom:0pt;font-size:11pt;font-family:times new roman;text-align:justify;"&gt;&lt;span style="font-style:italic"&gt;The fifth paragraph under the sub&#x2011;section of the Prospectus entitled &#x201c;Principal Investment Strategies&#x201d; under the section entitled &#x201c;Summary Section &#x2013; Bridge Builder Small/Mid Cap Growth Fund&#x201d; and the fifth paragraph under the corresponding sub&#x2011;section of the Summary Prospectus are hereby deleted and replaced with the following:&lt;/span&gt; &lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt;&lt;div style="margin-top:12pt;margin-bottom:0pt;margin-left:5%;font-size:11pt;font-family:times new roman;text-align:justify;"&gt;The Adviser is responsible for determining the amount of Fund assets to allocate to each Sub&#x2011;adviser. The Adviser allocates Fund assets for each investment strategy to the following Sub&#x2011;advisers: Artisan Partners Limited Partnership (&#x201c;Artisan Partners&#x201d;), Boston Partners Global Investors, Inc. (&#x201c;Boston Partners&#x201d;), Driehaus Capital Management LLC (&#x201c;Driehaus&#x201d;), Los Angeles Capital Management LLC (&#x201c;LA Capital&#x201d;), LSV Asset Management (&#x201c;LSV&#x201d;), Russell Investment Management, LLC (&#x201c;RIM&#x201d;), Stephens Investment Management Group, LLC (&#x201c;SIMG&#x201d;) and Vaughan Nelson Investment Management, L.P. (&#x201c;Vaughan Nelson&#x201d;). The Adviser may adjust allocations to the Sub&#x2011;advisers at any time or make recommendations to the Board with respect to the hiring, termination, or replacement of the Sub&#x2011;advisers. Below is a summary of each Sub&#x2011;adviser&#x2019;s principal investment strategies. &lt;/div&gt;
&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;font-family:times new roman;font-size:11pt;border-spacing:0px;width:100%"&gt; 
&lt;tr style="page-break-inside:avoid"&gt; 
&lt;td style="width:1%;"&gt;&#160;&lt;/td&gt; 
&lt;td style="width:4%;vertical-align:top;text-align:left;"&gt;3.&lt;/td&gt; 
&lt;td style="vertical-align:top;text-align:left;"&gt; &lt;div style="margin-top:0pt;margin-bottom:0pt;font-size:11pt;font-family:times new roman;text-align:justify;"&gt;&lt;span style="font-style:italic"&gt;The following paragraphs are hereby added to the sub&#x2011;section of the Prospectus entitled &#x201c;Principal Investment Strategies&#x201d; under the section entitled &#x201c;Summary Section &#x2013; Bridge Builder Small/Mid Cap Growth Fund&#x201d; and to the corresponding sub&#x2011;section of the Summary Prospectus:&lt;/span&gt; &lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt;&lt;div style="margin-top:12pt;margin-bottom:0pt;margin-left:5%;font-size:11pt;font-family:times new roman;font-weight:bold;"&gt;Boston Partners&#x2019; Principal Investment Strategies &lt;/div&gt;&lt;div style="margin-top:12pt;margin-bottom:0pt;margin-left:5%;font-size:11pt;font-family:times new roman;text-align:justify;"&gt;Boston Partners primarily invests in mid&#x2011;capitalization companies. Boston Partners uses bottom&#x2011;up fundamental analysis to make investment decisions. Boston Partners&#x2019; strategy is designed to identify companies with attractive valuations, sound business fundamentals, and improving business momentum. Boston Partners&#x2019; strategy seeks to add value through bottom&#x2011;up stock selection.&lt;span style="font-weight:bold"&gt; &lt;/span&gt; &lt;/div&gt;&lt;div style="margin-top:12pt;margin-bottom:0pt;margin-left:5%;font-size:11pt;font-family:times new roman;font-weight:bold;"&gt;LSV&#x2019;s Principal Investment Strategies &lt;/div&gt;&lt;div style="margin-top:12pt;margin-bottom:0pt;margin-left:5%;font-size:11pt;font-family:times new roman;text-align:justify;"&gt;LSV primarily invests in mid&#x2011;capitalization companies. LSV uses a bottom&#x2011;up investment style, seeking to identify companies that are trading at prices substantially below their intrinsic value. LSV follows an active investment strategy, focusing on using data and financial information and combining such information with the rigor of a quantitative model. &lt;/div&gt;&lt;div style="margin-top:0pt;margin-bottom:0pt;margin-left:5%;font-size:11pt;font-family:times new roman;font-weight:bold;"&gt;Vaughan Nelson&#x2019;s Principal Investment Strategies &lt;/div&gt;&lt;div style="margin-top:12pt;margin-bottom:0pt;margin-left:5%;font-size:11pt;font-family:times new roman;text-align:justify;"&gt;Vaughan Nelson primarily invests in mid&#x2011;capitalization companies with a focus on those companies meeting Vaughan Nelson&#x2019;s return expectations. Vaughan Nelson uses a bottom&#x2011;up value-oriented investment process in constructing its allocated portion of the Fund&#x2019;s portfolio. Vaughan Nelson seeks companies with the following characteristics, although not all of the companies selected will have these attributes: &lt;/div&gt;
&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;font-family:times new roman;font-size:11pt;border-spacing:0px;width:100%"&gt; 
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&lt;td style="width:16%;"&gt;&#160;&lt;/td&gt; 
&lt;td style="width:3%;vertical-align:top;text-align:left;"&gt;&#x2022;&lt;/td&gt; 
&lt;td style="width:1%;vertical-align:top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align:top;text-align:left;"&gt; &lt;div style="margin-top:0pt;margin-bottom:0pt;font-family:times new roman;font-size:11pt;text-align:justify;"&gt;Companies earning a positive return on capital with stable&#x2011;to&#x2011;improving returns; &lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt;
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&lt;td style="width:16%;"&gt;&#160;&lt;/td&gt; 
&lt;td style="width:3%;vertical-align:top;text-align:left;"&gt;&#x2022;&lt;/td&gt; 
&lt;td style="width:1%;vertical-align:top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align:top;text-align:left;"&gt; &lt;div style="margin-top:0pt;margin-bottom:0pt;font-family:times new roman;font-size:11pt;text-align:justify;"&gt;Companies valued at a discount to their asset value; and &lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt;
&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;font-family:times new roman;font-size:11pt;border-spacing:0px;width:100%"&gt; 
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&lt;td style="width:16%;"&gt;&#160;&lt;/td&gt; 
&lt;td style="width:3%;vertical-align:top;text-align:left;"&gt;&#x2022;&lt;/td&gt; 
&lt;td style="width:1%;vertical-align:top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align:top;text-align:left;"&gt; &lt;div style="margin-top:0pt;margin-bottom:0pt;font-family:times new roman;font-size:11pt;text-align:justify;"&gt;Companies with an attractive and sustainable dividend level. &lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt;</oef:SupplementToProspectusTextBlock>
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      id="t_4_31cea6fb_9774_a967_b99c_3df16f6d860e">&lt;div style="margin-top:0pt;margin-bottom:0pt;font-size:11pt;font-family:times new roman;font-weight:bold;text-align:center;"&gt;BRIDGE BUILDER TRUST &lt;/div&gt;&lt;div style="margin-top:12pt;margin-bottom:0pt;font-size:11pt;font-family:times new roman;font-weight:bold;text-align:center;"&gt;Bridge Builder Small/Mid Cap Growth Fund (the &#x201c;Fund&#x201d;) &lt;/div&gt;&lt;div style="margin-top:12pt;margin-bottom:0pt;font-size:11pt;font-family:times new roman;font-weight:bold;text-align:center;"&gt;Supplement dated September&#160;21, 2026 &lt;/div&gt;&lt;div style="margin-top:0pt;margin-bottom:0pt;font-size:11pt;font-family:times new roman;font-weight:bold;text-align:center;"&gt;to the Summary Prospectus dated October&#160;27, 2025, &lt;/div&gt;&lt;div style="margin-top:0pt;margin-bottom:0pt;font-size:11pt;font-family:times new roman;font-weight:bold;text-align:center;"&gt;as amended and restated June&#160;18, 2026 and as supplemented, and the &lt;/div&gt;&lt;div style="margin-top:0pt;margin-bottom:0pt;font-size:11pt;font-family:times new roman;font-weight:bold;text-align:center;"&gt;Prospectus dated October&#160;27, 2025, as supplemented &lt;/div&gt;&lt;div style="margin-top:12pt;margin-bottom:0pt;font-size:11pt;font-family:times new roman;font-weight:bold;text-align:center;"&gt;This supplement provides new and additional information beyond that contained in the &lt;/div&gt;&lt;div style="margin-top:0pt;margin-bottom:0pt;font-size:11pt;font-family:times new roman;font-weight:bold;text-align:center;"&gt;Summary Prospectus and Prospectus and should be read in conjunction with the Summary Prospectus and Prospectus. &lt;/div&gt;&lt;div style="margin-top:12pt;margin-bottom:0pt;font-size:11pt;font-family:times new roman;text-align:justify;"&gt;At a meeting held on August 19&#x2011;20, 2026, the Board of Trustees of Bridge Builder Trust (the &#x201c;Trust&#x201d;), upon the recommendation of Olive Street Investment Advisers, LLC, approved certain changes to the Fund, including (i)&#160;a change to the Fund&#x2019;s name to &#x201c;Bridge Builder Mid Cap Fund,&#x201d; (ii) changes to the Fund&#x2019;s principal investment strategy pursuant to which the Fund will invest primarily in mid&#x2011;capitalization companies and no longer invest primarily in both small- and mid&#x2011;capitalization companies or follow a growth-oriented investment style, and (iii)&#160;a new 80% investment policy to invest in securities of mid&#x2011;capitalization companies (collectively, the &#x201c;Repositioning&#x201d;). The Trust provided shareholders with notice of the Repositioning, including advance notice of the Fund&#x2019;s new 80% investment policy pursuant to Rule 35d&#x2011;1 under the Investment Company Act of 1940, in a supplement dated August&#160;24, 2026 (the &#x201c;August Supplement&#x201d;). The Repositioning is expected to be completed by October&#160;28, 2026. &lt;/div&gt;&lt;div style="margin-top:12pt;margin-bottom:0pt;font-size:11pt;font-family:times new roman;text-align:justify;"&gt;In connection with the Repositioning, the Board also approved the appointment of certain new sub&#x2011;advisers and the termination of certain existing sub&#x2011;advisory agreements, as previously disclosed in the August Supplement. The Fund is now beginning to implement changes in connection with the Repositioning on a phased basis. &lt;/div&gt;&lt;div style="margin-top:12pt;margin-bottom:0pt;font-size:11pt;font-family:times new roman;text-align:justify;"&gt;The changes described in this supplement are expected to be implemented in accordance with the approximate dates set forth below: &lt;/div&gt;
&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;font-family:times new roman;font-size:11pt;border-spacing:0px;width:100%"&gt; 
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&lt;td style="width:4%;"&gt;&#160;&lt;/td&gt; 
&lt;td style="width:3%;vertical-align:top;text-align:left;"&gt;&#x2022;&lt;/td&gt; 
&lt;td style="width:1%;vertical-align:top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align:top;text-align:left;"&gt; &lt;div style="margin-top:0pt;margin-bottom:0pt;font-family:times new roman;font-size:11pt;text-align:justify;"&gt;Effective on or about September&#160;25, 2026, Eagle Asset Management, Inc. (&#x201c;Eagle&#x201d;) and Federated MDTA LLC (&#x201c;Federated MDT&#x201d;) will no longer serve as subadvisers to each of their respective allocated portions of the Fund. &lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt;&lt;div style="margin-top:12pt;margin-bottom:0pt;margin-left:7%;font-size:11pt;font-family:times new roman;text-align:justify;"&gt;Effective on or about the same date, LSV Asset Management (&#x201c;LSV&#x201d;) and Vaughan Nelson Investment Management, L.P. (&#x201c;Vaughan Nelson&#x201d;) will each begin serving as a subadviser to an allocated portion of the Fund. Accordingly, the revisions described below relating to Eagle, Federated MDT, LSV and Vaughan Nelson will become effective on or about September&#160;25, 2026. &lt;/div&gt;
&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;font-family:times new roman;font-size:11pt;border-spacing:0px;width:100%"&gt; 
&lt;tr style="page-break-inside:avoid"&gt; 
&lt;td style="width:4%;"&gt;&#160;&lt;/td&gt; 
&lt;td style="width:3%;vertical-align:top;text-align:left;"&gt;&#x2022;&lt;/td&gt; 
&lt;td style="width:1%;vertical-align:top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align:top;text-align:left;"&gt; &lt;div style="margin-top:0pt;margin-bottom:0pt;font-family:times new roman;font-size:11pt;text-align:justify;"&gt;Effective on or about October&#160;2, 2026, Boston Partners Global Investors, Inc. (&#x201c;Boston Partners&#x201d;) will begin serving as a subadviser to an allocated portion of the Fund. Accordingly, the revisions described below relating to Boston Partners will become effective on or about October&#160;2, 2026. &lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt;&lt;div style="margin-top:0pt;margin-bottom:0pt;font-size:11pt;font-family:times new roman;text-align:justify;"&gt;Artisan Partners Limited Partnership, Driehaus Capital Management LLC, Los Angeles Capital Management LLC, Russell Investment Management, LLC and Stephens Investment Management Group, LLC will continue to serve as subadvisers to the Fund. &lt;/div&gt;&lt;div style="margin-top:12pt;margin-bottom:0pt;font-size:11pt;font-family:times new roman;text-align:justify;"&gt;Accordingly, the Summary Prospectus and Prospectus are hereby supplemented and revised as follows: &lt;/div&gt;
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&lt;tr style="page-break-inside:avoid"&gt; 
&lt;td style="width:1%;"&gt;&#160;&lt;/td&gt; 
&lt;td style="width:4%;vertical-align:top;text-align:left;"&gt;1.&lt;/td&gt; 
&lt;td style="vertical-align:top;text-align:left;"&gt; &lt;div style="margin-top:0pt;margin-bottom:0pt;font-size:11pt;font-family:times new roman;text-align:justify;"&gt;&lt;span style="font-style:italic"&gt;All references and information related to Eagle and Federated MDT, with respect to the Fund, are hereby deleted in their entirety.&lt;/span&gt; &lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt;
&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;font-family:times new roman;font-size:11pt;border-spacing:0px;width:100%"&gt; 
&lt;tr style="page-break-inside:avoid"&gt; 
&lt;td style="width:1%;"&gt;&#160;&lt;/td&gt; 
&lt;td style="width:4%;vertical-align:top;text-align:left;"&gt;2.&lt;/td&gt; 
&lt;td style="vertical-align:top;text-align:left;"&gt; &lt;div style="margin-top:0pt;margin-bottom:0pt;font-size:11pt;font-family:times new roman;text-align:justify;"&gt;&lt;span style="font-style:italic"&gt;The fifth paragraph under the sub&#x2011;section of the Prospectus entitled &#x201c;Principal Investment Strategies&#x201d; under the section entitled &#x201c;Summary Section &#x2013; Bridge Builder Small/Mid Cap Growth Fund&#x201d; and the fifth paragraph under the corresponding sub&#x2011;section of the Summary Prospectus are hereby deleted and replaced with the following:&lt;/span&gt; &lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt;&lt;div style="margin-top:12pt;margin-bottom:0pt;margin-left:5%;font-size:11pt;font-family:times new roman;text-align:justify;"&gt;The Adviser is responsible for determining the amount of Fund assets to allocate to each Sub&#x2011;adviser. The Adviser allocates Fund assets for each investment strategy to the following Sub&#x2011;advisers: Artisan Partners Limited Partnership (&#x201c;Artisan Partners&#x201d;), Boston Partners Global Investors, Inc. (&#x201c;Boston Partners&#x201d;), Driehaus Capital Management LLC (&#x201c;Driehaus&#x201d;), Los Angeles Capital Management LLC (&#x201c;LA Capital&#x201d;), LSV Asset Management (&#x201c;LSV&#x201d;), Russell Investment Management, LLC (&#x201c;RIM&#x201d;), Stephens Investment Management Group, LLC (&#x201c;SIMG&#x201d;) and Vaughan Nelson Investment Management, L.P. (&#x201c;Vaughan Nelson&#x201d;). The Adviser may adjust allocations to the Sub&#x2011;advisers at any time or make recommendations to the Board with respect to the hiring, termination, or replacement of the Sub&#x2011;advisers. Below is a summary of each Sub&#x2011;adviser&#x2019;s principal investment strategies. &lt;/div&gt;
&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;font-family:times new roman;font-size:11pt;border-spacing:0px;width:100%"&gt; 
&lt;tr style="page-break-inside:avoid"&gt; 
&lt;td style="width:1%;"&gt;&#160;&lt;/td&gt; 
&lt;td style="width:4%;vertical-align:top;text-align:left;"&gt;3.&lt;/td&gt; 
&lt;td style="vertical-align:top;text-align:left;"&gt; &lt;div style="margin-top:0pt;margin-bottom:0pt;font-size:11pt;font-family:times new roman;text-align:justify;"&gt;&lt;span style="font-style:italic"&gt;The following paragraphs are hereby added to the sub&#x2011;section of the Prospectus entitled &#x201c;Principal Investment Strategies&#x201d; under the section entitled &#x201c;Summary Section &#x2013; Bridge Builder Small/Mid Cap Growth Fund&#x201d; and to the corresponding sub&#x2011;section of the Summary Prospectus:&lt;/span&gt; &lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt;&lt;div style="margin-top:12pt;margin-bottom:0pt;margin-left:5%;font-size:11pt;font-family:times new roman;font-weight:bold;"&gt;Boston Partners&#x2019; Principal Investment Strategies &lt;/div&gt;&lt;div style="margin-top:12pt;margin-bottom:0pt;margin-left:5%;font-size:11pt;font-family:times new roman;text-align:justify;"&gt;Boston Partners primarily invests in mid&#x2011;capitalization companies. Boston Partners uses bottom&#x2011;up fundamental analysis to make investment decisions. Boston Partners&#x2019; strategy is designed to identify companies with attractive valuations, sound business fundamentals, and improving business momentum. Boston Partners&#x2019; strategy seeks to add value through bottom&#x2011;up stock selection.&lt;span style="font-weight:bold"&gt; &lt;/span&gt; &lt;/div&gt;&lt;div style="margin-top:12pt;margin-bottom:0pt;margin-left:5%;font-size:11pt;font-family:times new roman;font-weight:bold;"&gt;LSV&#x2019;s Principal Investment Strategies &lt;/div&gt;&lt;div style="margin-top:12pt;margin-bottom:0pt;margin-left:5%;font-size:11pt;font-family:times new roman;text-align:justify;"&gt;LSV primarily invests in mid&#x2011;capitalization companies. LSV uses a bottom&#x2011;up investment style, seeking to identify companies that are trading at prices substantially below their intrinsic value. LSV follows an active investment strategy, focusing on using data and financial information and combining such information with the rigor of a quantitative model. &lt;/div&gt;&lt;div style="margin-top:0pt;margin-bottom:0pt;margin-left:5%;font-size:11pt;font-family:times new roman;font-weight:bold;"&gt;Vaughan Nelson&#x2019;s Principal Investment Strategies &lt;/div&gt;&lt;div style="margin-top:12pt;margin-bottom:0pt;margin-left:5%;font-size:11pt;font-family:times new roman;text-align:justify;"&gt;Vaughan Nelson primarily invests in mid&#x2011;capitalization companies with a focus on those companies meeting Vaughan Nelson&#x2019;s return expectations. Vaughan Nelson uses a bottom&#x2011;up value-oriented investment process in constructing its allocated portion of the Fund&#x2019;s portfolio. Vaughan Nelson seeks companies with the following characteristics, although not all of the companies selected will have these attributes: &lt;/div&gt;
&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;font-family:times new roman;font-size:11pt;border-spacing:0px;width:100%"&gt; 
&lt;tr style="page-break-inside:avoid"&gt; 
&lt;td style="width:16%;"&gt;&#160;&lt;/td&gt; 
&lt;td style="width:3%;vertical-align:top;text-align:left;"&gt;&#x2022;&lt;/td&gt; 
&lt;td style="width:1%;vertical-align:top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align:top;text-align:left;"&gt; &lt;div style="margin-top:0pt;margin-bottom:0pt;font-family:times new roman;font-size:11pt;text-align:justify;"&gt;Companies earning a positive return on capital with stable&#x2011;to&#x2011;improving returns; &lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt;
&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;font-family:times new roman;font-size:11pt;border-spacing:0px;width:100%"&gt; 
&lt;tr style="page-break-inside:avoid"&gt; 
&lt;td style="width:16%;"&gt;&#160;&lt;/td&gt; 
&lt;td style="width:3%;vertical-align:top;text-align:left;"&gt;&#x2022;&lt;/td&gt; 
&lt;td style="width:1%;vertical-align:top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align:top;text-align:left;"&gt; &lt;div style="margin-top:0pt;margin-bottom:0pt;font-family:times new roman;font-size:11pt;text-align:justify;"&gt;Companies valued at a discount to their asset value; and &lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt;
&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;font-family:times new roman;font-size:11pt;border-spacing:0px;width:100%"&gt; 
&lt;tr style="page-break-inside:avoid"&gt; 
&lt;td style="width:16%;"&gt;&#160;&lt;/td&gt; 
&lt;td style="width:3%;vertical-align:top;text-align:left;"&gt;&#x2022;&lt;/td&gt; 
&lt;td style="width:1%;vertical-align:top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align:top;text-align:left;"&gt; &lt;div style="margin-top:0pt;margin-bottom:0pt;font-family:times new roman;font-size:11pt;text-align:justify;"&gt;Companies with an attractive and sustainable dividend level. &lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt;</oef:SupplementToProspectusTextBlock>
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    <oef:ProspectusDate
      contextRef="DefaultContext"
      id="t_2_7da54cf8_a2d3_34b5_6fd7_be218c4f40b7">2025-10-27</oef:ProspectusDate>
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