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style="font-size:14pt;font-weight:bold;text-transform:uppercase;">Securities And Exchange Commission</b><span style="font-size:14pt;font-variant:small-caps;"><br /></span><b style="font-weight:bold;">Washington, D.C. 20549</b></p><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;text-align:center;margin:0pt;"><span style="font-weight:bold;visibility:hidden;">&#8203;</span></p><p style="font-family:'Times New Roman','Times','serif';font-size:14pt;text-align:center;margin:0pt;"><b style="font-weight:bold;">FORM </b><ix:nonNumeric contextRef="Duration_7_25_2021_To_7_25_2021_TtN_GpbpV0KdM-m6njGDYA" name="dei:DocumentType" id="Narr_NhvxWHkxu06EHCfgQCjA2A"><b style="font-weight:bold;">8-K</b></ix:nonNumeric></p><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;text-align:center;margin:0pt;"><span style="font-size:14pt;font-variant:small-caps;font-weight:bold;visibility:hidden;">&#8203;</span></p><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;text-align:center;margin:0pt;"><b style="font-weight:bold;">Current Report</b></p><p style="font-family:'Times';font-size:12pt;font-variant:small-caps;font-weight:bold;line-height:1.19;text-align:center;margin:0pt 0pt 12pt 0pt;"><b style="font-family:'Times New Roman','Times','serif';font-weight:bold;">Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934</b></p><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;text-align:center;margin:0pt 0pt 12pt 0pt;"><span style="white-space:pre-wrap;">Date of Report (Date of earliest event reported):  </span><b style="font-weight:bold;">July 26, 2021 (</b><ix:nonNumeric contextRef="Duration_7_25_2021_To_7_25_2021_TtN_GpbpV0KdM-m6njGDYA" format="ixt:datemonthdayyearen" name="dei:DocumentPeriodEndDate" id="Narr_NspNN2inekWB_8xpvSzenQ"><b style="font-weight:bold;">July 25, 2021</b></ix:nonNumeric><b style="font-weight:bold;">)</b></p><p style="font-family:'Times New 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style="font-family:'Times';font-size:9pt;line-height:14pt;text-align:justify;text-indent:0pt;margin:0pt -9pt 10pt 0pt;"><span style="font-family:'Times New Roman','Times','serif';font-size:10pt;">If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. &#160;</span><b style="font-family:'Segoe UI Symbol';font-weight:bold;">&#9744;</b></p><p style="font-family:'Times';font-size:10pt;line-height:14pt;text-align:justify;text-indent:0pt;margin:0pt 0pt 10pt 0pt;"><span style="font-family:'Times New Roman','Times','serif';">Securities registered pursuant to Section 12(b) of the Act:</span></p><a id="_f25d6eed_7629_4afa_a308_081eec847f61"></a><a id="Tc_GewtlOKYqUaZWPoIuqWluQ_1_0"></a><a id="Tc_MkCFFMIrvkehoO_h2m_CMw_1_1"></a><a id="Tc_WBraV6ZRFECmXpXtWnhSRg_1_2"></a><table 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style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:center;margin:0pt 8.65pt 0pt 0pt;"><b style="font-weight:bold;">Trading Symbol(s)</b></p></td><td style="vertical-align:top;width:35.58%;border-bottom:1px solid #000000;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:center;margin:0pt -13.5pt 0pt 0pt;"><b style="font-weight:bold;white-space:pre-wrap;">Name of each exchange on  which registered</b></p></td></tr><tr><td style="vertical-align:top;width:40.38%;border-top:1px solid #000000;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;text-align:center;margin:0pt 8.65pt 0pt 0pt;"><ix:nonNumeric contextRef="Duration_7_25_2021_To_7_25_2021_TtN_GpbpV0KdM-m6njGDYA" name="dei:Security12bTitle" id="Tc_5Tbmm24ya0GxD_Og4-ghnw_2_0"><span style="font-size:10pt;">Common Stock</span></ix:nonNumeric></p></td><td style="vertical-align:bottom;width:24.03%;border-top:1px 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Roman','Times','serif';font-size:12pt;text-align:center;margin:0pt 8.65pt 0pt 0pt;"><span style="font-size:10pt;margin-right:0pt;visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:24.03%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;text-align:center;margin:0pt 8.65pt 0pt 0pt;"><span style="font-size:10pt;margin-right:0pt;visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:35.58%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;text-align:center;margin:0pt 8.65pt 0pt 0pt;"><span style="font-size:10pt;margin-right:0pt;visibility:hidden;">&#8203;</span></p></td></tr></table><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;padding-bottom:1pt;padding-top:1pt;border-bottom:3.0pt solid #000000;border-top:1.0pt solid #000000;margin:0pt;"><span style="font-size:1pt;font-weight:bold;visibility:hidden;">&#8203;</span></p><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p><p style="display:none;font-size:12pt;line-height:0pt;margin:0pt;"><span style="font-family:'Times New Roman','Times','serif';font-size:0pt;visibility:hidden;">&#8203;</span></p></div></div>
<div style="background-color:#000000;clear:both;height:2pt;page-break-after:always;width:91.06%;border:0;margin:30pt 4.47% 30pt 4.47%;"></div><div style="max-width:100%;padding-left:10.35%;padding-right:10.35%;position:relative;"><div style="clear:both;max-width:100%;position:relative;"><a id="_d62c3aeb_c0fe_4663_929c_d7ddd04d7490"></a><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;text-align:justify;margin:0pt;"><span style="font-size:1pt;visibility:hidden;">&#8203;</span></p><p style="background-color:#ffffff;font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;"><b style="font-weight:bold;">Item 1.01. Entry into a Definitive Material Agreement.</b></p><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;text-align:justify;text-indent:36pt;margin:0pt;"><span style="font-size:10pt;margin-bottom:5pt;margin-top:5pt;visibility:hidden;">&#8203;</span></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:justify;text-indent:36pt;margin:0pt;">On July 25, 2021, Old Second Bancorp, Inc. (&#8220;<span style="font-style:italic;font-weight:bold;">Old Second</span>&#8221;) and West Suburban Bancorp, Inc. (&#8220;<span style="font-style:italic;font-weight:bold;">West Suburba</span>n&#8221;) entered into an Agreement and Plan of Merger and Reorganization (the &#8220;<span style="font-style:italic;font-weight:bold;">Merger Agreement</span>&#8221;). &#160;The Merger Agreement provides that, upon the terms and subject to the conditions set forth therein, West Suburban will merge with and into Old Second, with Old Second continuing as the surviving entity (the &#8220;<span style="font-style:italic;font-weight:bold;">Merger</span>&#8221;). &#160;Immediately following the Merger, or at such later time as the parties may mutually agree, West Suburban Bank, an Illinois-chartered banking corporation and wholly-owned subsidiary of West Suburban, will merge with and into Old Second National Bank, a national banking association and wholly-owned subsidiary of Old Second, with Old Second National Bank continuing as the surviving bank (the &#8220;<span style="font-style:italic;font-weight:bold;">Bank Merger</span>&#8221;). &#160;The Merger Agreement was unanimously approved by the boards of directors of Old Second and West Suburban.</p><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;text-align:justify;text-indent:36pt;margin:0pt;"><span style="font-size:10pt;margin-bottom:5pt;margin-top:5pt;visibility:hidden;">&#8203;</span></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:justify;text-indent:36pt;margin:0pt;">Subject to the terms and conditions of the Merger Agreement, at the effective time of the Merger (the &#8220;<span style="font-style:italic;font-weight:bold;">Effective Time</span>&#8221;), each West Suburban shareholder will receive 42.413<span style="font-size:12pt;"> </span>shares (the &#8220;<span style="font-style:italic;font-weight:bold;">Exchange Ratio</span>&#8221;) of Old Second common stock and $271.15 in cash for each share of West Suburban common stock owned by the shareholder. &#160;</p><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;text-align:justify;text-indent:36pt;margin:0pt;"><span style="font-size:10pt;margin-bottom:5pt;margin-top:5pt;visibility:hidden;">&#8203;</span></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:justify;text-indent:36pt;margin:0pt;">The Merger Agreement provides that, effective immediately after the Effective Time, the respective boards of directors of Old Second and Old Second National Bank will each be increased in size by three, and three current members of the board of directors of West Suburban, which members will be mutually agreed to by Old Second and West Suburban, will be appointed to fill the resulting vacancies (which, with respect to Old Second, will include one new director in each of Class I, Class II and Class III). &#160;</p><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;text-align:justify;text-indent:36pt;margin:0pt;"><span style="font-size:10pt;visibility:hidden;">&#8203;</span></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:justify;text-indent:36pt;margin:0pt;">The Merger Agreement contains customary representations and warranties from both Old Second and West Suburban and each party has agreed to customary covenants, including, among others, covenants relating to the conduct of Old Second&#8217;s and West Suburban&#8217;s businesses during the interim period between the execution of the Merger Agreement and the Effective Time, and Old Second&#8217;s and West Suburban&#8217;s obligations to call meetings of their respective shareholders to adopt or approve the Merger Agreement and, subject to certain exceptions with respect to West Suburban, to recommend that their respective shareholders adopt or approve the Merger Agreement. &#160;West Suburban has also agreed not to solicit, initiate or knowingly encourage, induce or facilitate, inquiries or proposals with respect to, or, subject to certain exceptions generally related to its board of directors&#8217; exercise of its fiduciary duties (as set forth in the Merger Agreement), engage in any negotiations concerning, or provide any confidential information relating to, any alternative acquisition proposals.</p><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;text-align:justify;text-indent:36pt;margin:0pt;"><span style="font-size:10pt;margin-bottom:5pt;margin-top:5pt;visibility:hidden;">&#8203;</span></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:justify;text-indent:36pt;margin:0pt;">The completion of the Merger is subject to customary conditions, including, among others, (a) the adoption of the Merger Agreement and the transactions contemplated thereby by the holders of Old Second common stock, (b) the approval of the Merger Agreement and the transactions contemplated thereby by the holders of &#160;West Suburban common stock, (c) the receipt of required regulatory approvals including the approval of the Board of Governors of the Federal Reserve System (in connection with the Merger) and the Office of the Comptroller of the Currency (in connection with the Bank Merger), (d) the effectiveness under the Securities Act of 1933, as amended, of the Registration Statement on Form S-4 for the Old Second common stock to be issued in the Merger, (e) the absence of any order, injunction or other legal restraint preventing the completion of the Merger or making the consummation of the Merger illegal, (f) authorization for listing on the Nasdaq Stock Market of the shares of Old Second common stock to be issued in the Merger, and (g) receipt by such party of an opinion from its tax advisor or counsel, as applicable, to the effect that the Merger will qualify as a reorganization within the meaning of Section 368(a) of the Internal Revenue Code of 1986, as amended. Each party&#8217;s obligation to complete the Merger is also subject to certain additional customary conditions, including (i) subject to certain exceptions, the accuracy of the representations and warranties of the other party, generally subject to a material adverse effect qualification, (ii) performance in all material respects by the other party of its obligations under the Merger Agreement, and (iii) the absence of a material adverse effect with respect to the other party during a specified period of time prior to the consummation of the Merger.</p><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;text-align:justify;text-indent:36pt;margin:0pt;"><span style="font-size:10pt;margin-bottom:5pt;margin-top:5pt;visibility:hidden;">&#8203;</span></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:justify;text-indent:36pt;margin:0pt 0pt 12pt 0pt;">The Merger Agreement provides certain termination rights for both Old Second and West Suburban and further provides that a termination fee of $11,875,000 will be payable by West Suburban to Old Second upon termination of the Merger Agreement under certain circumstances.</p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:justify;text-indent:36pt;margin:0pt;">In connection with the Merger Agreement, certain shareholders of West Suburban, including each director of West Suburban and West Suburban Bank, and certain other officers and shareholders of West Suburban, entered into </p></div><div style="clear:both;margin-bottom:30pt;width:100%;"><p style="font-family:'Courier';font-size:12pt;text-align:center;margin:0pt;"><span style="font-family:'Times New Roman','Times','serif';font-size:10pt;visibility:hidden;">&#8203;</span></p></div></div>
<div style="background-color:#000000;clear:both;height:2pt;page-break-after:always;width:79.3%;border:0;margin:30pt 10.35% 30pt 10.35%;"></div><div style="max-width:100%;padding-left:10.35%;padding-right:10.35%;position:relative;"><div style="clear:both;max-width:100%;position:relative;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:justify;margin:0pt;">voting and support agreements with Old Second (the &#8220;<span style="font-style:italic;font-weight:bold;">Support Agreements</span>&#8221;) in which he or she has agreed, among other things, to vote the shares of West Suburban common stock owned beneficially or of record by such shareholder in favor of the Merger Agreement and the Merger at the special meeting of West Suburban shareholders at which these matters are to be considered.</p><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;text-align:justify;margin:0pt;"><span style="font-size:10pt;visibility:hidden;">&#8203;</span></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:justify;text-indent:36pt;margin:0pt 0pt 12pt 0pt;">The foregoing description of the Merger Agreement and Support Agreements does not purport to be complete and is qualified in its entirety by reference to the full text of the Merger Agreement, which is filed as <span style="text-decoration:underline;text-decoration-color:#000000;">Exhibit 2.1</span> hereto, and the forms of Support Agreements, which are exhibits to the Merger Agreement, each of which are incorporated herein by reference. &#160;</p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:justify;text-indent:36pt;margin:0pt 0pt 12pt 0pt;">The representations, warranties and covenants of each party set forth in the Merger Agreement have been made only for purposes of, and were and are solely for the benefit of the parties to, the Merger Agreement, may be subject to limitations agreed upon by the contracting parties, including being qualified by confidential disclosures made for the purposes of allocating contractual risk between Old Second and West Suburban instead of establishing these matters as facts, and may be subject to standards of materiality applicable to the contracting parties that differ from those applicable to investors. &#160;Accordingly, the representations and warranties may not describe the actual state of affairs at the date they were made or at any other time, and investors should not rely on them as statements of fact. In addition, such representations and warranties (a)&#160;will not survive consummation of the Merger, unless otherwise specified therein, and (b)&#160;were made only as of the date of the Merger Agreement or such other date as is specified in the Merger Agreement. &#160;Moreover, information concerning the subject matter of the representations and warranties may change after the date of the Merger Agreement, which subsequent information may or may not be fully reflected in the parties&#8217; public disclosures. &#160;Accordingly, the Merger Agreement is included with this filing only to provide investors with information regarding the terms of the Merger Agreement, and not to provide investors with any other factual information regarding Old Second or West Suburban, their respective affiliates or their respective businesses. The Merger Agreement should not be read alone, but should instead be read in conjunction with the other information regarding Old Second, West Suburban, their respective affiliates or their respective businesses, the Merger Agreement and the Merger that will be contained in, or incorporated by reference into, the Registration Statement on Form S-4 to be filed by Old Second under the Securities Act of 1933, as amended, that will include a Joint Proxy Statement of Old Second and West Suburban and a Prospectus of Old Second, as well as in the Form 10-K, Forms 10-Q and other filings that Old Second makes with the Securities and Exchange Commission (&#8220;<span style="font-style:italic;font-weight:bold;">SEC</span>&#8221;).</p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;"><b style="font-weight:bold;">Item 8.01. Other Events.</b></p><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;margin:0pt;"><b style="font-weight:bold;">&#160;</b></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:justify;text-indent:36pt;margin:0pt;">On July 26, 2021, Old Second and West Suburban issued a joint press release announcing the execution of the Merger Agreement. &#160;A copy of the press release is filed as <span style="text-decoration:underline;text-decoration-color:#000000;">Exhibit 99.1</span> hereto and is incorporated herein by reference. &#160;</p><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;text-align:justify;text-indent:36pt;margin:0pt;"><span style="font-size:10pt;visibility:hidden;">&#8203;</span></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:justify;text-indent:36pt;margin:0pt;">Old Second will conduct a live conference call to discuss the proposed transaction today, July 26, 2021, at 10:30&#160;a.m. Eastern Time (9:30&#160;a.m.&#160;Central Time). To listen to the live call, please dial 877-407-9124. Investors should call into the dial-in number set forth above at least 10 minutes prior to the scheduled start of the call. </p><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;text-align:justify;text-indent:36pt;margin:0pt;"><span style="font-size:10pt;visibility:hidden;">&#8203;</span></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:justify;text-indent:36pt;margin:0pt;">A copy of the investor presentation to be used on the call is attached as <span style="text-decoration:underline;text-decoration-color:#000000;">Exhibit 99.2</span> to this Current Report on Form 8-K and is incorporated herein by reference. &#160;The investor presentation will also be available on the Old Second website (www.oldsecond.com). &#160;</p><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;text-align:justify;text-indent:36pt;margin:0pt;"><span style="font-size:10pt;visibility:hidden;">&#8203;</span></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:justify;text-indent:36pt;margin:0pt;">An audio replay of the call will be available until 11:00&#160;a.m. Eastern Time (10:00&#160;a.m. Central Time) on August 2, 2021, by dialing 877-481-4010, using Conference ID: 42334.</p><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;text-align:justify;text-indent:36pt;margin:0pt;"><span style="font-size:10pt;visibility:hidden;">&#8203;</span></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:center;margin:0pt 0pt 12pt 0pt;">****</p></div></div>
<div style="background-color:#000000;clear:both;height:2pt;page-break-after:always;width:79.3%;border:0;margin:30pt 10.35% 30pt 10.35%;"></div><div style="max-width:100%;padding-left:10.35%;padding-right:10.35%;position:relative;"><div style="clear:both;max-width:100%;position:relative;"><p style="font-family:'Arial','Helvetica','sans-serif';font-size:10pt;line-height:1.19;text-align:justify;margin:0pt;"><b style="font-family:'Times New Roman','Times','serif';font-weight:bold;">Cautionary Note Regarding Forward-Looking Statements</b></p><p style="font-family:'Arial','Helvetica','sans-serif';font-size:11pt;line-height:1.19;text-align:justify;margin:0pt;"><span style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.27;margin-bottom:8pt;visibility:hidden;">&#8203;</span></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:justify;text-indent:36pt;margin:0pt;">Statements included in this Form 8-K, or incorporated herein by reference, which are not historical in nature are intended to be, and hereby are identified as, forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. &#160;Examples of forward-looking statements include, but are not limited to, statements regarding the outlook and expectations of Old Second and West Suburban with respect to their planned merger, the strategic and financial benefits of the merger and the timing of the closing of the transaction. &#160;Words such as &#8220;may,&#8221; &#8220;anticipate,&#8221; &#8220;plan,&#8221; &#8220;estimate,&#8221; &#8220;expect,&#8221; &#8220;project,&#8221; &#8220;assume,&#8221; &#8220;approximately,&#8221; &#8220;continue,&#8221; &#8220;should,&#8221; &#8220;could,&#8221; &#8220;will,&#8221; &#8220;poised,&#8221; &#8220;focused,&#8221; &#8220;targeted,&#8221; &#8220;opportunity,&#8221; &#8220;plans&#8221; and variations of such words and similar expressions are intended to identify such forward-looking statements. </p><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;text-align:justify;text-indent:36pt;margin:0pt;"><span style="font-size:10pt;visibility:hidden;">&#8203;</span></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:justify;text-indent:36pt;margin:0pt;">Forward-looking statements are subject to risks, uncertainties and assumptions that are difficult to predict with regard to timing, extent, likelihood and degree of occurrence, which could cause actual results to differ materially from anticipated results. Such risks, uncertainties and assumptions, include, among others, the following: </p><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;text-align:justify;margin:0pt;"><span style="font-size:10pt;visibility:hidden;">&#8203;</span></p><table style="border-collapse:collapse;font-family:'Calibri','Helvetica','sans-serif';font-size:11pt;margin-bottom:0pt;margin-top:0pt;table-layout:fixed;text-align:justify;width:100%;border:0pt;"><tr><td style="width:18pt;"></td><td style="font-family:'Times New Roman';font-size:10pt;vertical-align:text-top;white-space:nowrap;width:18pt;padding:0pt;">&#9679;</td><td style="padding:0pt;"><span style="font-family:'Times New Roman','Times','serif';font-size:10pt;font-style:normal;font-weight:normal;text-align:justify;">the failure to obtain necessary regulatory approvals when expected or at all (and the risk that such approvals may result in the imposition of conditions that could adversely affect the combined company or the expected benefits of the transaction);</span></td></tr></table><table style="border-collapse:collapse;font-family:'Calibri','Helvetica','sans-serif';font-size:11pt;margin-bottom:0pt;margin-top:0pt;table-layout:fixed;text-align:justify;width:100%;border:0pt;"><tr><td style="width:18pt;"></td><td style="font-family:'Times New Roman';font-size:10pt;vertical-align:text-top;white-space:nowrap;width:18pt;padding:0pt;">&#9679;</td><td style="padding:0pt;"><span style="font-family:'Times New Roman','Times','serif';font-size:10pt;font-style:normal;font-weight:normal;text-align:justify;">the failure of either company to obtain shareholder approval, or the failure of either company to satisfy any of the other closing conditions to the transaction on a timely basis or at all;</span></td></tr></table><table style="border-collapse:collapse;font-family:'Calibri','Helvetica','sans-serif';font-size:11pt;margin-bottom:0pt;margin-top:0pt;table-layout:fixed;text-align:justify;width:100%;border:0pt;"><tr><td style="width:18pt;"></td><td style="font-family:'Times New Roman';font-size:10pt;vertical-align:text-top;white-space:nowrap;width:18pt;padding:0pt;">&#9679;</td><td style="padding:0pt;"><span style="font-family:'Times New Roman','Times','serif';font-size:10pt;font-style:normal;font-weight:normal;text-align:justify;">the occurrence of any event, change or other circumstances that could give rise to the right of one or both of the parties to terminate the merger agreement;</span></td></tr></table><table style="border-collapse:collapse;font-family:'Calibri','Helvetica','sans-serif';font-size:11pt;margin-bottom:0pt;margin-top:0pt;table-layout:fixed;text-align:justify;width:100%;border:0pt;"><tr><td style="width:18pt;"></td><td style="font-family:'Times New Roman';font-size:10pt;vertical-align:text-top;white-space:nowrap;width:18pt;padding:0pt;">&#9679;</td><td style="padding:0pt;"><span style="font-family:'Times New Roman','Times','serif';font-size:10pt;font-style:normal;font-weight:normal;text-align:justify;">the possibility that the anticipated benefits of the transaction, including anticipated cost savings and strategic gains, are not realized when expected or at all, including as a result of the impact of, or problems arising from, the integration of the two companies or as a result of the strength of the economy, competitive factors in the areas where Old Second and West Suburban do business, or as a result of other unexpected factors or events; </span></td></tr></table><table style="border-collapse:collapse;font-family:'Calibri','Helvetica','sans-serif';font-size:11pt;margin-bottom:0pt;margin-top:0pt;table-layout:fixed;text-align:justify;width:100%;border:0pt;"><tr><td style="width:18pt;"></td><td style="font-family:'Times New Roman';font-size:10pt;vertical-align:text-top;white-space:nowrap;width:18pt;padding:0pt;">&#9679;</td><td style="padding:0pt;"><span style="font-family:'Times New Roman','Times','serif';font-size:10pt;font-style:normal;font-weight:normal;text-align:justify;">the impact of purchase accounting with respect to the transaction, or any change in the assumptions used regarding the assets purchased and liabilities assumed to determine their fair value;</span></td></tr></table><table style="border-collapse:collapse;font-family:'Calibri','Helvetica','sans-serif';font-size:11pt;margin-bottom:0pt;margin-top:0pt;table-layout:fixed;text-align:justify;width:100%;border:0pt;"><tr><td style="width:18pt;"></td><td style="font-family:'Times New Roman';font-size:10pt;vertical-align:text-top;white-space:nowrap;width:18pt;padding:0pt;">&#9679;</td><td style="padding:0pt;"><span style="font-family:'Times New Roman','Times','serif';font-size:10pt;font-style:normal;font-weight:normal;text-align:justify;">diversion of management&#8217;s attention from ongoing business operations and opportunities; </span></td></tr></table><table style="border-collapse:collapse;font-family:'Calibri','Helvetica','sans-serif';font-size:11pt;margin-bottom:0pt;margin-top:0pt;table-layout:fixed;text-align:justify;width:100%;border:0pt;"><tr><td style="width:18pt;"></td><td style="font-family:'Times New Roman';font-size:10pt;vertical-align:text-top;white-space:nowrap;width:18pt;padding:0pt;">&#9679;</td><td style="padding:0pt;"><span style="font-family:'Times New Roman','Times','serif';font-size:10pt;font-style:normal;font-weight:normal;text-align:justify;">potential adverse reactions or changes to business or employee relationships, including those resulting from the announcement or completion of the transaction; </span></td></tr></table><table style="border-collapse:collapse;font-family:'Calibri','Helvetica','sans-serif';font-size:11pt;margin-bottom:0pt;margin-top:0pt;table-layout:fixed;text-align:justify;width:100%;border:0pt;"><tr><td style="width:18pt;"></td><td style="font-family:'Times New Roman';font-size:10pt;vertical-align:text-top;white-space:nowrap;width:18pt;padding:0pt;">&#9679;</td><td style="padding:0pt;"><span style="font-family:'Times New Roman','Times','serif';font-size:10pt;font-style:normal;font-weight:normal;text-align:justify;">the outcome of any legal proceedings that may be instituted against Old Second or West Suburban;</span></td></tr></table><table style="border-collapse:collapse;font-family:'Calibri','Helvetica','sans-serif';font-size:11pt;margin-bottom:0pt;margin-top:0pt;table-layout:fixed;text-align:justify;width:100%;border:0pt;"><tr><td style="width:18pt;"></td><td style="font-family:'Times New Roman';font-size:10pt;vertical-align:text-top;white-space:nowrap;width:18pt;padding:0pt;">&#9679;</td><td style="padding:0pt;"><span style="font-family:'Times New Roman','Times','serif';font-size:10pt;font-style:normal;font-weight:normal;text-align:justify;">the integration of the businesses and operations of Old Second and West Suburban, which may take longer than anticipated or be more costly than anticipated or have unanticipated adverse results relating to Old Second&#8217;s and West Suburban&#8217;s existing businesses; </span></td></tr></table><table style="border-collapse:collapse;font-family:'Calibri','Helvetica','sans-serif';font-size:11pt;margin-bottom:0pt;margin-top:0pt;table-layout:fixed;text-align:justify;width:100%;border:0pt;"><tr><td style="width:18pt;"></td><td style="font-family:'Times New Roman';font-size:10pt;vertical-align:text-top;white-space:nowrap;width:18pt;padding:0pt;">&#9679;</td><td style="padding:0pt;"><span style="font-family:'Times New Roman','Times','serif';font-size:10pt;font-style:normal;font-weight:normal;text-align:justify;">business disruptions following the merger; and </span></td></tr></table><table style="border-collapse:collapse;font-family:'Calibri','Helvetica','sans-serif';font-size:11pt;margin-bottom:0pt;margin-top:0pt;table-layout:fixed;text-align:justify;width:100%;border:0pt;"><tr><td style="width:18pt;"></td><td style="font-family:'Times New Roman';font-size:10pt;vertical-align:text-top;white-space:nowrap;width:18pt;padding:0pt;">&#9679;</td><td style="padding:0pt;"><span style="font-family:'Times New Roman','Times','serif';font-size:10pt;font-style:normal;font-weight:normal;text-align:justify;">other factors that may affect future results of Old Second and West Suburban including changes in asset quality and credit risk; the inability to sustain revenue and earnings growth; changes in interest rates and capital markets; inflation; customer borrowing, repayment, investment and deposit practices; changes in general economic conditions, including due to the COVID-19 pandemic; the impact, extent and timing of technological changes; capital management activities; and other actions of the Federal Reserve Board and legislative and regulatory actions and reforms.</span></td></tr></table><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;text-align:justify;text-indent:36pt;margin:0pt;"><span style="font-size:10pt;visibility:hidden;">&#8203;</span></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:justify;text-indent:36pt;margin:0pt;">Annualized, pro forma, projected and estimated numbers are used for illustrative purpose only, are not forecasts and may not reflect actual results. Old Second disclaims any obligation to update or revise any forward-looking statements contained in this Form 8-K, which speak only as of the date hereof, whether as a result of new information, future events or otherwise, except as required by law. &#160;Additional factors that could cause results to differ materially from those described above can be found in Old Second&#8217;s Annual Report on Form 10-K for the year ended December 31, 2020, which is on file with the SEC and available on Old Second&#8217;s investor relations website, https://investors.oldsecond.com, under the heading &#8220;SEC Filings,&#8221; and in other documents Old Second files with the SEC. </p><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;text-align:justify;margin:0pt;"><span style="font-size:10pt;visibility:hidden;">&#8203;</span></p><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;text-align:justify;margin:0pt;"><span style="font-size:10pt;visibility:hidden;">&#8203;</span></p></div></div>
<div style="background-color:#000000;clear:both;height:2pt;page-break-after:always;width:79.3%;border:0;margin:30pt 10.35% 30pt 10.35%;"></div><div style="max-width:100%;padding-left:10.35%;padding-right:10.35%;position:relative;"><div style="clear:both;max-width:100%;position:relative;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;font-weight:bold;text-align:justify;margin:0pt;"><b style="font-weight:bold;letter-spacing:-0.05pt;">Additional Information About the Merger and Where to Find It</b></p><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;text-align:justify;margin:0pt;"><span style="font-size:10pt;visibility:hidden;">&#8203;</span></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:justify;text-indent:36pt;margin:0pt;">This communication is being made in respect of the proposed merger transaction between Old Second and West Suburban. In connection with the proposed merger, Old Second will file with the SEC a Registration Statement on Form S-4 that will include the Joint Proxy Statement of Old Second and West Suburban and a Prospectus of Old Second, as well as other relevant documents regarding the proposed transaction. A definitive Joint Proxy Statement/Prospectus will also be sent to Old Second stockholders and West Suburban shareholders. </p><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;text-align:justify;margin:0pt;"><span style="font-size:10pt;visibility:hidden;">&#8203;</span></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:justify;text-indent:36pt;margin:0pt;">INVESTORS ARE URGED TO READ THE REGISTRATION STATEMENT AND THE JOINT PROXY STATEMENT/PROSPECTUS REGARDING THE MERGER WHEN IT BECOMES AVAILABLE AND ANY OTHER RELEVANT DOCUMENTS FILED WITH THE SEC, AS WELL AS ANY AMENDMENTS OR SUPPLEMENTS TO THOSE DOCUMENTS, BECAUSE THEY WILL CONTAIN IMPORTANT INFORMATION.</p><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;text-align:justify;margin:0pt;"><span style="font-size:10pt;visibility:hidden;">&#8203;</span></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:justify;text-indent:36pt;margin:0pt;">This communication does not constitute an offer to sell or the solicitation of an offer to buy any securities or a solicitation of any vote or approval, nor shall there be any sale of securities in any jurisdiction in which such offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of such jurisdiction.</p><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;text-align:justify;text-indent:36pt;margin:0pt;"><span style="font-size:10pt;visibility:hidden;">&#8203;</span></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:justify;text-indent:36pt;margin:0pt;">A free copy of the Joint Proxy Statement/Prospectus (when it becomes available), as well as other filings containing information about Old Second, may be obtained at the SEC&#8217;s Internet site (http://www.sec.gov). You will also be able to obtain these documents, free of charge, from Old Second by accessing Old Second&#8217;s investor relations website, https://investors.oldsecond.com, under the heading &#8220;SEC Filings&#8221; or by directing a request to Old Second Shareholder Relations Manager, Shirley Cantrell, at Old Second Bancorp, Inc., 37 S. River St., Aurora, Illinois 60507, by calling 630-906-2303 or by sending an e-mail to scantrell@oldsecond.com.</p><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;text-align:justify;margin:0pt;"><span style="font-size:10pt;visibility:hidden;">&#8203;</span></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:justify;margin:0pt;"><b style="font-weight:bold;">Participants in the Solicitation</b></p><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;text-align:justify;margin:0pt;"><span style="font-size:10pt;visibility:hidden;">&#8203;</span></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:justify;text-indent:36pt;margin:0pt;">Old Second and West Suburban and certain of their respective directors and executive officers may be deemed to be participants in the solicitation of proxies from Old Second&#8217;s stockholders and West Suburban&#8217;s shareholders in connection with the proposed merger. Information regarding Old Second&#8217;s directors and executive officers is contained in Old Second&#8217;s definitive proxy statement on Schedule 14A, dated April 16, 2021 and in certain of its Current Reports on Form 8-K, which are filed with the SEC. Additional information regarding the interests of those participants and other persons who may be deemed participants in the transaction may be obtained by reading the Joint Proxy Statement/Prospectus regarding the proposed merger when it becomes available. Free copies of these documents may be obtained as described in the preceding paragraph.</p><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;text-align:justify;margin:0pt;"><span style="font-size:10pt;font-weight:bold;visibility:hidden;">&#8203;</span></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;"><b style="font-weight:bold;">Item 9.01&#160;Financial Statements and Exhibits.</b></p><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p><table style="border-collapse:collapse;font-size:16pt;height:max-content;margin-left:auto;margin-right:auto;width:100%;"><tr><td style="vertical-align:bottom;width:10.38%;border-bottom:1px solid #000000;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:center;margin:0pt;"><b style="font-weight:bold;">Exhibit No.</b></p></td><td style="vertical-align:bottom;width:2.59%;border-bottom:1px solid transparent;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;"><b style="font-weight:bold;">&#160;&#160;&#160;&#160;</b></p></td><td style="vertical-align:bottom;width:87.01%;border-bottom:1px solid #000000;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:center;margin:0pt;"><b style="font-weight:bold;">Exhibit</b></p></td></tr><tr><td style="vertical-align:top;width:10.38%;border-top:1px solid #000000;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;margin:0pt;"><span style="font-size:10pt;visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:2.59%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;margin:0pt;"><span style="font-size:10pt;visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:87.01%;border-top:1px solid #000000;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;margin:0pt;"><span style="font-size:10pt;visibility:hidden;">&#8203;</span></p></td></tr><tr><td style="vertical-align:top;width:10.38%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;">2.1</p></td><td style="vertical-align:top;width:2.59%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;margin:0pt;"><span style="font-size:10pt;visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:87.01%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;margin:0pt;"><a style="-sec-extract:exhibit;" href="tmb-20210725xex2d1.htm"><span style="font-family:'Times New Roman','Times','serif';font-size:10pt;font-style:normal;font-weight:normal;text-align:left;">Agreement and Plan of Merger between Old Second Bancorp, Inc. and West Suburban Bancorp, Inc. dated as of July 25, 2021+</span></a></p><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;margin:0pt;"><span style="font-size:10pt;visibility:hidden;">&#8203;</span></p></td></tr><tr><td style="vertical-align:top;width:10.38%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;">99.1</p></td><td style="vertical-align:top;width:2.59%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:87.01%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;margin:0pt;"><a style="-sec-extract:exhibit;" href="tmb-20210725xex99d1.htm"><span style="font-family:'Times New Roman','Times','serif';font-size:10pt;font-style:normal;font-weight:normal;text-align:left;">Joint Press Release dated July 26, 2021</span></a></p></td></tr><tr><td style="vertical-align:top;width:10.38%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;margin:0pt;"><span style="font-size:10pt;visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:2.59%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;margin:0pt;"><span style="font-size:10pt;visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:87.01%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;margin:0pt;"><span style="font-size:10pt;visibility:hidden;">&#8203;</span></p></td></tr><tr><td style="vertical-align:top;width:10.38%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;">99.2</p></td><td style="vertical-align:top;width:2.59%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:87.01%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;margin:0pt;"><a style="-sec-extract:exhibit;" href="tmb-20210725xex99d2.htm"><span style="font-family:'Times New Roman','Times','serif';font-size:10pt;font-style:normal;font-weight:normal;text-align:left;">Investor Presentation</span></a></p><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;margin:0pt;"><span style="font-size:10pt;visibility:hidden;">&#8203;</span></p></td></tr><tr><td style="vertical-align:top;width:10.38%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;">104</p></td><td style="vertical-align:top;width:2.59%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;margin:0pt;"><span style="font-size:10pt;visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:87.01%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;">Cover Page Interactive Data File (the cover page XBRL tags are embedded within the Inline XBRL document).</p></td></tr><tr><td style="vertical-align:top;width:10.38%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;margin:0pt;"><span style="font-size:10pt;visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:2.59%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;margin:0pt;"><span style="font-size:10pt;visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:87.01%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;margin:0pt;"><span style="font-size:10pt;visibility:hidden;">&#8203;</span></p></td></tr><tr><td style="vertical-align:top;width:10.38%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;">+</p></td><td style="vertical-align:top;width:2.59%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;margin:0pt;"><span style="font-size:10pt;visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:87.01%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;">Schedules and similar attachments have been omitted pursuant to Item 601(b)(2) of Regulation S-K. The registrant will furnish supplementally a copy of any omitted schedules or similar attachment to the SEC upon request.</p></td></tr></table><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;text-align:justify;margin:0pt 8.65pt 12pt 0pt;"><span style="font-size:10pt;font-weight:bold;margin-right:0pt;visibility:hidden;">&#8203;</span></p><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;margin:0pt;"><span style="font-size:10pt;font-weight:bold;visibility:hidden;">&#8203;</span></p></div></div>
<div style="background-color:#000000;clear:both;height:2pt;page-break-after:always;width:79.3%;border:0;margin:30pt 10.35% 30pt 10.35%;"></div><div style="max-width:100%;padding-left:10.35%;padding-right:10.35%;position:relative;"><div style="clear:both;max-width:100%;position:relative;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:center;margin:0pt 8.65pt 12pt 0pt;"><b style="font-weight:bold;">Signature</b></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-indent:36pt;margin:0pt 8.65pt 0pt 0pt;">Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.</p><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;text-indent:36pt;margin:0pt 8.65pt 0pt 0pt;"><span style="font-size:10pt;margin-right:0pt;visibility:hidden;">&#8203;</span></p><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;text-indent:36pt;margin:0pt 8.65pt 0pt 0pt;"><span style="font-size:10pt;margin-right:0pt;visibility:hidden;">&#8203;</span></p><table style="border-collapse:collapse;font-size:16pt;height:max-content;padding-left:0pt;padding-right:0pt;width:100%;"><tr style="height:1pt;"><td style="vertical-align:top;width:50.28%;margin:0pt;padding:0pt;"><div style="height:1pt;overflow:hidden;overflow-wrap:break-word;position:relative;"><div style="position:absolute;top:0pt;width:100%;"><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;line-height:1.25;margin:0pt 8.65pt 0pt 0pt;"><span style="font-family:'CG Times';font-size:1pt;margin-right:0pt;visibility:hidden;">&#8203;</span></p></div></div></td><td style="vertical-align:top;width:4.75%;margin:0pt;padding:0pt;"><div style="height:1pt;overflow:hidden;overflow-wrap:break-word;position:relative;"><div style="position:absolute;top:0pt;width:100%;"><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;line-height:1.25;margin:0pt 8.65pt 0pt 0pt;"><span style="font-family:'CG Times';font-size:1pt;margin-right:0pt;visibility:hidden;">&#8203;</span></p></div></div></td><td style="vertical-align:top;width:44.95%;margin:0pt;padding:0pt;"><div style="height:1pt;overflow:hidden;overflow-wrap:break-word;position:relative;"><div style="position:absolute;top:0pt;width:100%;"><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;line-height:1.25;margin:0pt 8.65pt 0pt 0pt;"><span style="font-family:'CG Times';font-size:1pt;margin-right:0pt;visibility:hidden;">&#8203;</span></p></div></div></td></tr><tr><td style="vertical-align:top;width:50.28%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;line-height:1.25;margin:0pt 8.65pt 0pt 0pt;"><span style="font-family:'CG Times';font-size:10pt;margin-right:0pt;visibility:hidden;">&#8203;</span></p></td><td colspan="2" 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Roman','Times','serif';font-size:12pt;line-height:1.25;margin:0pt 8.65pt 0pt 0pt;"><span style="font-family:'CG Times';font-size:10pt;margin-right:0pt;visibility:hidden;">&#8203;</span></p></td></tr><tr><td style="vertical-align:top;width:50.28%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;line-height:1.25;margin:0pt 8.65pt 0pt 0pt;"><span style="font-family:'CG Times';font-size:10pt;margin-right:0pt;visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:4.75%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;line-height:1.25;margin:0pt 8.65pt 0pt 0pt;"><span style="font-family:'CG Times';font-size:10pt;margin-right:0pt;visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:44.95%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;line-height:1.25;margin:0pt 8.65pt 0pt 0pt;"><span style="font-family:'CG Times';font-size:10pt;margin-right:0pt;visibility:hidden;">&#8203;</span></p></td></tr><tr><td style="vertical-align:top;width:50.28%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.25;margin:0pt 8.65pt 0pt 0pt;">Dated: July 26, 2021</p></td><td style="vertical-align:top;width:4.75%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.25;margin:0pt 8.65pt 0pt 0pt;">By:</p></td><td style="vertical-align:top;width:44.95%;border-bottom:1px solid #000000;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.25;margin:0pt 8.65pt 0pt 0pt;"><span style="font-family:'CG Times';">/s/ Bradley S. Adams</span></p></td></tr><tr><td style="vertical-align:top;width:50.28%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;line-height:1.25;margin:0pt 8.65pt 0pt 0pt;"><span style="font-family:'CG Times';font-size:10pt;margin-right:0pt;visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:4.75%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;line-height:1.25;margin:0pt 8.65pt 0pt 0pt;"><span style="font-family:'CG Times';font-size:10pt;margin-right:0pt;visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:44.95%;border-top:1px solid #000000;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.25;margin:0pt 8.65pt 0pt 0pt;"><span style="font-family:'CG Times';">Bradley S. Adams</span></p></td></tr><tr><td style="vertical-align:top;width:50.28%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;line-height:1.25;margin:0pt 8.65pt 0pt 0pt;"><span style="font-family:'CG Times';font-size:10pt;margin-right:0pt;visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:4.75%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;line-height:1.25;margin:0pt 8.65pt 0pt 0pt;"><span style="font-family:'CG Times';font-size:10pt;margin-right:0pt;visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:44.95%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.25;margin:0pt 8.65pt 0pt 0pt;">Executive Vice President and</p></td></tr><tr><td style="vertical-align:top;width:50.28%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;line-height:1.25;margin:0pt 8.65pt 0pt 0pt;"><span style="font-family:'CG Times';font-size:10pt;margin-right:0pt;visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:4.75%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;line-height:1.25;margin:0pt 8.65pt 0pt 0pt;"><span style="font-family:'CG Times';font-size:10pt;margin-right:0pt;visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:44.95%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.25;margin:0pt 8.65pt 0pt 0pt;">Chief Financial Officer</p></td></tr></table><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;margin:0pt;"><span style="font-size:10pt;visibility:hidden;">&#8203;</span></p><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;margin:0pt;"><span style="font-size:10pt;visibility:hidden;">&#8203;</span></p></div></div>
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{"company-data": {"conformed-name": "OLD SECOND BANCORP INC", "cik": "0000357173", "assigned-sic": "6022", "irs-number": "363143493", "state-of-incorporation": "DE", "fiscal-year-end": "1231"}, "filing-values": {"form-type": "8-K", "act": "34", "file-number": "000-10537", "film-number": "211112308"}, "business-address": {"street1": "37 S RIVER ST", "city": "AURORA", "state": "IL", "zip": "60507", "phone": "6308920202"}, "mail-address": {"street1": "37 SOUTH RIVER STREET", "city": "AURORA", "state": "IL", "zip": "60507"}}
Old Second Bancorp, Inc
​
I
​
United States
Securities And Exchange Commission
Washington, D.C. 20549
​
FORM
8-K
​
Current Report
Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934
Date of Report (Date of earliest event reported):
July 26, 2021 (
July 25, 2021
)
(Exact
name of registrant
as specified in its charter)
​
​
​
Delaware
000-10537
36-3143493
(State or other jurisdiction of incorporation)
(Commission File Number)
(I.R.S. Employer Identification No.)
​
37 South River Street
Aurora
,
Illinois
60507
(Address of principal executive offices) (Zip code)
(
630
)
892-0202
(Registrant's telephone number, including area code)
N/A
(Former name or former address, if changed since last report)
Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (
see
General Instruction A.2. below):
☒
Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)
☐
Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)
☐
Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))
☐
Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))
Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 under the Securities Act (17 CFR 230.405) or Rule 12b-2 under the Exchange Act (17 CFR 240.12b-2).
Emerging growth company
☐
If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.
☐
Securities registered pursuant to Section 12(b) of the Act:
​
​
​
​
Title of each class
Trading Symbol(s)
Name of each exchange on  which registered
Common Stock
OSBC
The Nasdaq Stock Market
​
​
​
​
​
​
Item 1.01. Entry into a Definitive Material Agreement.
​
On July 25, 2021, Old Second Bancorp, Inc. ("
Old Second
") and West Suburban Bancorp, Inc. ("
West Suburba
n") entered into an Agreement and Plan of Merger and Reorganization (the "
Merger Agreement
").  The Merger Agreement provides that, upon the terms and subject to the conditions set forth therein, West Suburban will merge with and into Old Second, with Old Second continuing as the surviving entity (the "
Merger
").  Immediately following the Merger, or at such later time as the parties may mutually agree, West Suburban Bank, an Illinois-chartered banking corporation and wholly-owned subsidiary of West Suburban, will merge with and into Old Second National Bank, a national banking association and wholly-owned subsidiary of Old Second, with Old Second National Bank continuing as the surviving bank (the "
Bank Merger
").  The Merger Agreement was unanimously approved by the boards of directors of Old Second and West Suburban.
​
Subject to the terms and conditions of the Merger Agreement, at the effective time of the Merger (the "
Effective Time
"), each West Suburban shareholder will receive 42.413
shares (the "
Exchange Ratio
") of Old Second common stock and $271.15 in cash for each share of West Suburban common stock owned by the shareholder.
​
The Merger Agreement provides that, effective immediately after the Effective Time, the respective boards of directors of Old Second and Old Second National Bank will each be increased in size by three, and three current members of the board of directors of West Suburban, which members will be mutually agreed to by Old Second and West Suburban, will be appointed to fill the resulting vacancies (which, with respect to Old Second, will include one new director in each of Class I, Class II and Class III).
​
The Merger Agreement contains customary representations and warranties from both Old Second and West Suburban and each party has agreed to customary covenants, including, among others, covenants relating to the conduct of Old Second's and West Suburban's businesses during the interim period between the execution of the Merger Agreement and the Effective Time, and Old Second's and West Suburban's obligations to call meetings of their respective shareholders to adopt or approve the Merger Agreement and, subject to certain exceptions with respect to West Suburban, to recommend that their respective shareholders adopt or approve the Merger Agreement.  West Suburban has also agreed not to solicit, initiate or knowingly encourage, induce or facilitate, inquiries or proposals with respect to, or, subject to certain exceptions generally related to its board of directors' exercise of its fiduciary duties (as set forth in the Merger Agreement), engage in any negotiations concerning, or provide any confidential information relating to, any alternative acquisition proposals.
​
The completion of the Merger is subject to customary conditions, including, among others, (a) the adoption of the Merger Agreement and the transactions contemplated thereby by the holders of Old Second common stock, (b) the approval of the Merger Agreement and the transactions contemplated thereby by the holders of  West Suburban common stock, (c) the receipt of required regulatory approvals including the approval of the Board of Governors of the Federal Reserve System (in connection with the Merger) and the Office of the Comptroller of the Currency (in connection with the Bank Merger), (d) the effectiveness under the Securities Act of 1933, as amended, of the Registration Statement on Form S-4 for the Old Second common stock to be issued in the Merger, (e) the absence of any order, injunction or other legal restraint preventing the completion of the Merger or making the consummation of the Merger illegal, (f) authorization for listing on the Nasdaq Stock Market of the shares of Old Second common stock to be issued in the Merger, and (g) receipt by such party of an opinion from its tax advisor or counsel, as applicable, to the effect that the Merger will qualify as a reorganization within the meaning of Section 368(a) of the Internal Revenue Code of 1986, as amended. Each party's obligation to complete the Merger is also subject to certain additional customary conditions, including (i) subject to certain exceptions, the accuracy of the representations and warranties of the other party, generally subject to a material adverse effect qualification, (ii) performance in all material respects by the other party of its obligations under the Merger Agreement, and (iii) the absence of a material adverse effect with respect to the other party during a specified period of time prior to the consummation of the Merger.
​
The Merger Agreement provides certain termination rights for both Old Second and West Suburban and further provides that a termination fee of $11,875,000 will be payable by West Suburban to Old Second upon termination of the Merger Agreement under certain circumstances.
In connection with the Merger Agreement, certain shareholders of West Suburban, including each director of West Suburban and West Suburban Bank, and certain other officers and shareholders of West Suburban, entered into
​
voting and support agreements with Old Second (the "
Support Agreements
") in which he or she has agreed, among other things, to vote the shares of West Suburban common stock owned beneficially or of record by such shareholder in favor of the Merger Agreement and the Merger at the special meeting of West Suburban shareholders at which these matters are to be considered.
​
The foregoing description of the Merger Agreement and Support Agreements does not purport to be complete and is qualified in its entirety by reference to the full text of the Merger Agreement, which is filed as
Exhibit 2.1
hereto, and the forms of Support Agreements, which are exhibits to the Merger Agreement, each of which are incorporated herein by reference.
The representations, warranties and covenants of each party set forth in the Merger Agreement have been made only for purposes of, and were and are solely for the benefit of the parties to, the Merger Agreement, may be subject to limitations agreed upon by the contracting parties, including being qualified by confidential disclosures made for the purposes of allocating contractual risk between Old Second and West Suburban instead of establishing these matters as facts, and may be subject to standards of materiality applicable to the contracting parties that differ from those applicable to investors.  Accordingly, the representations and warranties may not describe the actual state of affairs at the date they were made or at any other time, and investors should not rely on them as statements of fact. In addition, such representations and warranties (a) will not survive consummation of the Merger, unless otherwise specified therein, and (b) were made only as of the date of the Merger Agreement or such other date as is specified in the Merger Agreement.  Moreover, information concerning the subject matter of the representations and warranties may change after the date of the Merger Agreement, which subsequent information may or may not be fully reflected in the parties' public disclosures.  Accordingly, the Merger Agreement is included with this filing only to provide investors with information regarding the terms of the Merger Agreement, and not to provide investors with any other factual information regarding Old Second or West Suburban, their respective affiliates or their respective businesses. The Merger Agreement should not be read alone, but should instead be read in conjunction with the other information regarding Old Second, West Suburban, their respective affiliates or their respective businesses, the Merger Agreement and the Merger that will be contained in, or incorporated by reference into, the Registration Statement on Form S-4 to be filed by Old Second under the Securities Act of 1933, as amended, that will include a Joint Proxy Statement of Old Second and West Suburban and a Prospectus of Old Second, as well as in the Form 10-K, Forms 10-Q and other filings that Old Second makes with the Securities and Exchange Commission ("
SEC
").
Item 8.01. Other Events.
On July 26, 2021, Old Second and West Suburban issued a joint press release announcing the execution of the Merger Agreement.  A copy of the press release is filed as
Exhibit 99.1
hereto and is incorporated herein by reference.
​
Old Second will conduct a live conference call to discuss the proposed transaction today, July 26, 2021, at 10:30 a.m. Eastern Time (9:30 a.m. Central Time). To listen to the live call, please dial 877-407-9124. Investors should call into the dial-in number set forth above at least 10 minutes prior to the scheduled start of the call.
​
A copy of the investor presentation to be used on the call is attached as
Exhibit 99.2
to this Current Report on Form 8-K and is incorporated herein by reference.  The investor presentation will also be available on the Old Second website (www.oldsecond.com).
​
An audio replay of the call will be available until 11:00 a.m. Eastern Time (10:00 a.m. Central Time) on August 2, 2021, by dialing 877-481-4010, using Conference ID: 42334.
​
****
Cautionary Note Regarding Forward-Looking Statements
​
Statements included in this Form 8-K, or incorporated herein by reference, which are not historical in nature are intended to be, and hereby are identified as, forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995.  Examples of forward-looking statements include, but are not limited to, statements regarding the outlook and expectations of Old Second and West Suburban with respect to their planned merger, the strategic and financial benefits of the merger and the timing of the closing of the transaction.  Words such as "may," "anticipate," "plan," "estimate," "expect," "project," "assume," "approximately," "continue," "should," "could," "will," "poised," "focused," "targeted," "opportunity," "plans" and variations of such words and similar expressions are intended to identify such forward-looking statements.
​
Forward-looking statements are subject to risks, uncertainties and assumptions that are difficult to predict with regard to timing, extent, likelihood and degree of occurrence, which could cause actual results to differ materially from anticipated results. Such risks, uncertainties and assumptions, include, among others, the following:
​
●
the failure to obtain necessary regulatory approvals when expected or at all (and the risk that such approvals may result in the imposition of conditions that could adversely affect the combined company or the expected benefits of the transaction);
●
the failure of either company to obtain shareholder approval, or the failure of either company to satisfy any of the other closing conditions to the transaction on a timely basis or at all;
●
the occurrence of any event, change or other circumstances that could give rise to the right of one or both of the parties to terminate the merger agreement;
●
the possibility that the anticipated benefits of the transaction, including anticipated cost savings and strategic gains, are not realized when expected or at all, including as a result of the impact of, or problems arising from, the integration of the two companies or as a result of the strength of the economy, competitive factors in the areas where Old Second and West Suburban do business, or as a result of other unexpected factors or events;
●
the impact of purchase accounting with respect to the transaction, or any change in the assumptions used regarding the assets purchased and liabilities assumed to determine their fair value;
●
diversion of management's attention from ongoing business operations and opportunities;
●
potential adverse reactions or changes to business or employee relationships, including those resulting from the announcement or completion of the transaction;
●
the outcome of any legal proceedings that may be instituted against Old Second or West Suburban;
●
the integration of the businesses and operations of Old Second and West Suburban, which may take longer than anticipated or be more costly than anticipated or have unanticipated adverse results relating to Old Second's and West Suburban's existing businesses;
●
business disruptions following the merger; and
●
other factors that may affect future results of Old Second and West Suburban including changes in asset quality and credit risk; the inability to sustain revenue and earnings growth; changes in interest rates and capital markets; inflation; customer borrowing, repayment, investment and deposit practices; changes in general economic conditions, including due to the COVID-19 pandemic; the impact, extent and timing of technological changes; capital management activities; and other actions of the Federal Reserve Board and legislative and regulatory actions and reforms.
​
Annualized, pro forma, projected and estimated numbers are used for illustrative purpose only, are not forecasts and may not reflect actual results. Old Second disclaims any obligation to update or revise any forward-looking statements contained in this Form 8-K, which speak only as of the date hereof, whether as a result of new information, future events or otherwise, except as required by law.  Additional factors that could cause results to differ materially from those described above can be found in Old Second's Annual Report on Form 10-K for the year ended December 31, 2020, which is on file with the SEC and available on Old Second's investor relations website, https://investors.oldsecond.com, under the heading "SEC Filings," and in other documents Old Second files with the SEC.
​
​
Additional Information About the Merger and Where to Find It
​
This communication is being made in respect of the proposed merger transaction between Old Second and West Suburban. In connection with the proposed merger, Old Second will file with the SEC a Registration Statement on Form S-4 that will include the Joint Proxy Statement of Old Second and West Suburban and a Prospectus of Old Second, as well as other relevant documents regarding the proposed transaction. A definitive Joint Proxy Statement/Prospectus will also be sent to Old Second stockholders and West Suburban shareholders.
​
INVESTORS ARE URGED TO READ THE REGISTRATION STATEMENT AND THE JOINT PROXY STATEMENT/PROSPECTUS REGARDING THE MERGER WHEN IT BECOMES AVAILABLE AND ANY OTHER RELEVANT DOCUMENTS FILED WITH THE SEC, AS WELL AS ANY AMENDMENTS OR SUPPLEMENTS TO THOSE DOCUMENTS, BECAUSE THEY WILL CONTAIN IMPORTANT INFORMATION.
​
This communication does not constitute an offer to sell or the solicitation of an offer to buy any securities or a solicitation of any vote or approval, nor shall there be any sale of securities in any jurisdiction in which such offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of such jurisdiction.
​
A free copy of the Joint Proxy Statement/Prospectus (when it becomes available), as well as other filings containing information about Old Second, may be obtained at the SEC's Internet site (http://www.sec.gov). You will also be able to obtain these documents, free of charge, from Old Second by accessing Old Second's investor relations website, https://investors.oldsecond.com, under the heading "SEC Filings" or by directing a request to Old Second Shareholder Relations Manager, Shirley Cantrell, at Old Second Bancorp, Inc., 37 S. River St., Aurora, Illinois 60507, by calling 630-906-2303 or by sending an e-mail to scantrell@oldsecond.com.
​
Participants in the Solicitation
​
Old Second and West Suburban and certain of their respective directors and executive officers may be deemed to be participants in the solicitation of proxies from Old Second's stockholders and West Suburban's shareholders in connection with the proposed merger. Information regarding Old Second's directors and executive officers is contained in Old Second's definitive proxy statement on Schedule 14A, dated April 16, 2021 and in certain of its Current Reports on Form 8-K, which are filed with the SEC. Additional information regarding the interests of those participants and other persons who may be deemed participants in the transaction may be obtained by reading the Joint Proxy Statement/Prospectus regarding the proposed merger when it becomes available. Free copies of these documents may be obtained as described in the preceding paragraph.
​
Item 9.01 Financial Statements and Exhibits.
​
Exhibit No.
Exhibit
​
​
​
2.1
​
Agreement and Plan of Merger between Old Second Bancorp, Inc. and West Suburban Bancorp, Inc. dated as of July 25, 2021+
​
99.1
​
Joint Press Release dated July 26, 2021
​
​
​
99.2
​
Investor Presentation
​
104
​
Cover Page Interactive Data File (the cover page XBRL tags are embedded within the Inline XBRL document).
​
​
​
+
​
Schedules and similar attachments have been omitted pursuant to Item 601(b)(2) of Regulation S-K. The registrant will furnish supplementally a copy of any omitted schedules or similar attachment to the SEC upon request.
​
​
Signature
Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.
​
​
​
​
​
​
OLD SECOND BANCORP, INC.
​
​
​
​
​
​
Dated: July 26, 2021
By:
/s/ Bradley S. Adams
​
​
Bradley S. Adams
​
​
Executive Vice President and
​
​
Chief Financial Officer
​
​