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<title>Document</title></head><body><div id="i15349b956198436ca89e54c90c36e30b_1"></div><div style="min-height:49.5pt;width:100%"><div style="text-align:center"><font><br></font></div></div><div style="text-align:center"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:120%">As filed with the Securities and Exchange Commission on May 20, 2025</font></div><div style="text-align:center"><font><br></font></div><div style="text-align:right"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:120%">Registration No.&#160;333-   </font></div><div><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:4pt;font-weight:400;line-height:120%">&#160;</font></div><div style="margin-bottom:1pt;text-align:center"><table style="border-collapse:collapse;display:inline-table;margin-bottom:5pt;vertical-align:text-bottom;width:99.882%"><tr><td style="width:1.0%"></td><td style="width:98.900%"></td><td style="width:0.1%"></td></tr><tr><td colspan="3" style="border-bottom:1pt solid #000;padding:2px 1pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:120%">&#160;&#160;</font></td></tr></table></div><div style="text-align:center"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:18pt;font-weight:700;line-height:120%">UNITED STATES </font></div><div style="text-align:center"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:18pt;font-weight:700;line-height:120%">SECURITIES AND EXCHANGE COMMISSION </font></div><div style="text-align:center"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:700;line-height:120%">Washington, D.C. 20549 </font></div><div style="margin-bottom:1pt;text-align:center"><font><br></font></div><div style="text-align:center"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:18pt;font-weight:700;line-height:120%">FORM S-8 </font></div><div style="text-align:center"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:700;line-height:120%">REGISTRATION STATEMENT UNDER </font></div><div style="text-align:center"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:700;line-height:120%">THE SECURITIES ACT OF 1933 </font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:120%">&#160;</font></div><div style="margin-top:7pt;text-align:center"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:18pt;font-weight:700;line-height:120%">EXAGEN INC. </font></div><div style="text-align:center"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">(Exact name of registrant as specified in its charter) </font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:120%">&#160;</font></div><div style="margin-bottom:1pt;text-align:center"><table style="border-collapse:collapse;display:inline-table;margin-bottom:5pt;vertical-align:text-bottom;width:89.630%"><tr><td style="width:1.0%"></td><td style="width:32.886%"></td><td style="width:0.1%"></td><td style="width:0.1%"></td><td style="width:0.780%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:30.926%"></td><td style="width:0.1%"></td><td style="width:0.1%"></td><td style="width:0.780%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:30.928%"></td><td style="width:0.1%"></td></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:middle"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:120%">&#160;</font></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:120%">Delaware</font></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">&#160;</font></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">&#160;</font></td><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:120%">20-0434866</font></td></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:top"><div style="text-align:center"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:120%">(State or other jurisdiction of</font></div><div style="margin-bottom:1pt;text-align:center"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:120%">incorporation or organization)</font></div></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">&#160;</font></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">&#160;</font></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:top"><div style="text-align:center"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:120%">(I.R.S. Employer</font></div><div style="margin-bottom:1pt;text-align:center"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:120%">Identification No.)</font></div></td></tr></table></div><div style="margin-top:7pt;text-align:center"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:120%">1261 Liberty Way </font></div><div style="text-align:center"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:120%">Vista, California 92081 </font></div><div style="margin-top:4pt;text-align:center"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">(Address of principal executive offices) (Zip code) </font></div><div style="margin-top:7pt;text-align:center"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:120%">Exagen Inc. 2019 Incentive Award Plan</font></div><div style="text-align:center"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:120%">Exagen Inc. 2019 Employee Stock Purchase Plan</font></div><div style="text-align:center"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">(Full title of the plans)</font></div><div style="text-align:center"><table style="border-collapse:collapse;display:inline-table;margin-bottom:5pt;vertical-align:text-bottom;width:99.882%"><tr><td style="width:1.0%"></td><td style="width:98.900%"></td><td style="width:0.1%"></td></tr><tr><td colspan="3" style="border-bottom:1pt solid #000000;padding:2px 1pt;text-align:center;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:120%">&#160;</font></td></tr></table></div><div style="text-align:center"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:120%">John Aballi </font></div><div style="text-align:center"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:120%">President and Chief Executive Officer </font></div><div style="text-align:center"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:120%">Exagen Inc. </font></div><div style="text-align:center"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:120%">1261 Liberty Way </font></div><div style="text-align:center"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:120%">Vista, California 92081 </font></div><div style="text-align:center"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:120%">(760) 560-1501 </font></div><div style="text-align:center"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">(Name, address, and telephone number, including area code, of agent for service) &#160;</font></div><div style="margin-bottom:1pt;margin-top:8pt"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company or an emerging growth company. See the definitions of &#8220;large accelerated filer,&#8221; &#8220;accelerated filer,&#8221; &#8220;smaller reporting company,&#8221; and &#8220;emerging growth company&#8221; in Rule 12b-2 of the Exchange Act. </font></div><div><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:120%">&#160;</font></div><div style="margin-bottom:1pt;margin-top:6pt;text-align:center"><table style="border-collapse:collapse;display:inline-table;margin-bottom:5pt;vertical-align:text-bottom;width:92.120%"><tr><td style="width:1.0%"></td><td style="width:20.521%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:20.521%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:7.962%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:24.973%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:20.523%"></td><td style="width:0.1%"></td></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">Large accelerated filer</font></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">&#9744;</font></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">Accelerated filer</font></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">&#9744;</font></td></tr><tr style="height:5pt"><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">Non-accelerated filer</font></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">&#9746;</font></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">Smaller reporting company</font></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">&#9746;</font></td></tr><tr style="height:5pt"><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td></tr><tr><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">Emerging growth company</font></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">&#9744;</font></td></tr></table></div><div style="margin-top:8pt"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">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 7(a)(2)(B) of the Securities Act. </font><font style="color:#000000;font-family:'Wingdings',sans-serif;font-size:10pt;font-weight:400;line-height:120%">&#9744;</font></div><div><font><br></font></div><div style="margin-top:2pt;text-align:center"><font><br></font></div><div><font><br></font></div><div style="height:43pt;position:relative;width:100%"><div style="bottom:0;position:absolute;width:100%"><div><font><br></font></div></div></div><div id="i15349b956198436ca89e54c90c36e30b_4"></div><hr style="page-break-after:always"><div style="min-height:72pt;width:100%"><div style="text-align:center"><font><br></font></div></div><div style="text-align:center"><font><br></font></div><div style="text-align:center"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:120%">EXPLANATORY NOTE</font></div><div style="margin-top:12pt;text-indent:18pt"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">This Registration Statement on Form S-8 is being filed with the Securities and Exchange Commission (the &#34;SEC&#34;) for the purpose of registering an additional 882,016 shares of common stock of Exagen Inc. (the &#34;Registrant&#34;) issuable or which may become issuable under the Exagen Inc. 2019 Incentive Award Plan (the &#34;2019 Plan&#34;) and the Exagen Inc. 2019 Employee Stock Purchase Plan (the &#34;2019 ESPP&#34;) pursuant to the evergreen provision of such plans.</font></div><div style="margin-top:12pt;text-indent:18pt"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">Pursuant to General Instruction E on Form S-8, the contents of the prior registration statements on Form S-8, File Nos. 333-233878, 333-256014, 333-264867, 333-272038 and 333-279356, previously filed with respect to the 2019 Plan and 2019 ESPP, are incorporated into this Registration Statement by reference to the extent not modified or superseded hereby or by any subsequently filed document, which is incorporated by reference herein or therein. </font></div><div id="i15349b956198436ca89e54c90c36e30b_7"></div><div style="margin-top:12pt;text-align:center;text-indent:18pt"><font><br></font></div><div style="text-align:center"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:120%">PART I</font></div><div style="margin-top:12pt;text-align:center;text-indent:18pt"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:120%">INFORMATION REQUIRED IN THE SECTION 10(a) PROSPECTUS</font></div><div style="margin-top:12pt;text-indent:18pt"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">The documents containing the information specified in Part I of Form S-8 will be sent or given to participants as specified by Rule 428(b)(1) of the Securities Act of 1933, as amended (the &#34;Securities Act&#34;). These documents and the documents incorporated by reference into this Registration Statement pursuant to Item 3 of Part II of this Registration Statement, taken together, constitute a prospectus that meets the requirements of Section 10(a) of the Securities Act.</font></div><div id="i15349b956198436ca89e54c90c36e30b_10"></div><div style="margin-top:12pt;text-align:center;text-indent:18pt"><font><br></font></div><div style="text-align:center"><font><br></font></div><div style="text-align:center"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:120%">PART II</font></div><div style="margin-top:12pt;text-align:center;text-indent:18pt"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:120%">INFORMATION REQUIRED IN THE REGISTRATION STATEMENT</font></div><div style="margin-top:12pt;text-indent:18pt"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:400;line-height:120%">In this Registration Statement, Exagen Inc. is sometimes referred to as &#34;Registrant,&#34; &#34;we,&#34; &#34;us&#34; or &#34;our.&#34;</font></div><div style="margin-top:12pt"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:120%">Item 3. Incorporation of Documents by Reference</font></div><div style="margin-top:12pt;text-indent:18pt"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">The Securities and Exchange Commission allows us to &#34;incorporate by reference&#34; the information we file with them, which means that we can disclose important information to you by referring you to those documents. The information incorporated by reference is considered to be part of this Registration Statement, and later information filed with the SEC will update and supersede this information. We hereby incorporate by reference into this Registration Statement the following documents previously filed with the SEC&#58;</font></div><div style="margin-top:6pt;padding-left:36pt;text-indent:-18pt"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">&#8226;</font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;padding-left:14.5pt">The Registrant's Annual Report on Form 10-K for the year ended December 31, 2024, filed with the SEC on </font><font style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;text-decoration:underline"><a href="https://www.sec.gov/ix?doc=/Archives/edgar/data/0001274737/000127473725000019/exdx-20241231.htm" style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;text-decoration:underline">March 11, 2025</a></font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">, including the information incorporated by reference into our Annual Report on Form 10-K from our definitive proxy statement for our 2025 Annual Meeting of Stockholders, filed with the SEC on </font><font style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;text-decoration:underline"><a href="https://www.sec.gov/ix?doc=/Archives/edgar/data/0001274737/000119312525105576/d920432ddef14a.htm" style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;text-decoration:underline">April 30, 2025</a></font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">&#59;</font></div><div style="margin-top:6pt;padding-left:36pt;text-indent:-18pt"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">&#8226;</font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;padding-left:14.5pt">The Registrant's Quarterly Report on Form 10-Q for the quarter ended March 31, 2025, filed with the SEC on </font><font style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;text-decoration:underline"><a href="https://www.sec.gov/ix?doc=/Archives/edgar/data/0001274737/000127473725000026/exdx-20250331.htm" style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;text-decoration:underline">May 5, 2025</a></font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">&#59;</font></div><div style="margin-top:6pt;padding-left:36pt;text-indent:-18pt"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">&#8226;</font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;padding-left:14.5pt">The Registrant's Current Reports on Form 8-K filed with the SEC on </font><font style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;text-decoration:underline"><a href="https://www.sec.gov/ix?doc=/Archives/edgar/data/0001274737/000127473725000003/exdx-20250112.htm" style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;text-decoration:underline">January 13, 2025</a></font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">, </font><font style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;text-decoration:underline"><a href="https://www.sec.gov/ix?doc=/Archives/edgar/data/0001274737/000127473725000018/exdx-20250311.htm" style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;text-decoration:underline">March 11, 2025</a></font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">, </font><font style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;text-decoration:underline"><a href="https://www.sec.gov/ix?doc=/Archives/edgar/data/0001274737/000119312525100447/d811854d8k.htm" style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;text-decoration:underline">April 28, 2025</a></font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">, </font><font style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;text-decoration:underline"><a href="https://www.sec.gov/ix?doc=/Archives/edgar/data/0001274737/000127473725000023/exdx-20250505.htm" style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;text-decoration:underline">May 5, 2025</a></font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">, </font><font style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;text-decoration:underline"><a href="https://www.sec.gov/ix?doc=/Archives/edgar/data/0001274737/000119312525115946/d788679d8k.htm" style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;text-decoration:underline">May 8, 2025</a></font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> and </font><font style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;text-decoration:underline"><a href="https://www.sec.gov/ix?doc=/Archives/edgar/data/0001274737/000119312525116881/d916977d8k.htm" style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;text-decoration:underline">M</a><a href="https://www.sec.gov/ix?doc=/Archives/edgar/data/0001274737/000119312525116881/d916977d8k.htm" style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;text-decoration:underline">ay 9, 2025</a></font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">&#59; and</font></div><div style="margin-top:6pt;padding-left:36pt;text-indent:-18pt"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">&#8226;</font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;padding-left:14.5pt">The description of the Registrant's common stock set forth in the Registrant's registration statement on Form 8-A12B (Registration No. 001-39049), filed by the Registrant with the SEC under Section 12(b) of the Securities Exchange Act of 1934, as amended (the &#34;Exchange Act&#34;), on </font><font style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;text-decoration:underline"><a href="https://www.sec.gov/Archives/edgar/data/1274737/000119312519244881/d756255d8a12b.htm" style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;text-decoration:underline">September 13, 2019</a></font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">, including any amendments or reports filed for the purpose of updating such description.</font></div><div style="height:72pt;position:relative;width:100%"><div style="bottom:0;position:absolute;width:100%"><div><font><br></font></div></div></div><hr style="page-break-after:always"><div style="min-height:72pt;width:100%"><div style="text-align:center"><font><br></font></div></div><div style="margin-top:12pt;text-indent:18pt"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">In addition, all documents filed by the Registrant pursuant to Section 13(a), 13(c), 14 or 15(d) of the Exchange Act subsequent to the filing of this registration statement and prior to the filing of a post-effective amendment which indicates that all securities offered hereby have been sold or which de-registers all securities then remaining unsold shall be deemed to be incorporated by reference into this registration statement and to be a part hereof from the date of filing such documents, except as to specific sections of such statements as set forth therein. Any statement contained in a document incorporated or deemed to be incorporated by reference herein shall be deemed to be modified or superseded for purposes of this registration statement to the extent that a statement contained herein or in any other subsequently filed document which also is incorporated or deemed to be incorporated by reference herein modifies or supersedes such statement. Any statement contained herein shall be deemed to be modified or superseded for purposes of this registration statement to the extent that a statement contained in any subsequently filed document which also is incorporated or deemed to be incorporated by reference herein modifies or supersedes such statement. Any such statement so modified or superseded shall not be deemed, except as so modified or superseded, to constitute a part of this registration statement.</font></div><div style="margin-top:12pt;text-indent:18pt"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">Under no circumstances shall any information furnished under Item 2.02 or 7.01 of Form 8-K be deemed incorporated herein by reference unless such Form 8-K expressly provides to the contrary.</font></div><div style="margin-top:12pt;text-indent:18pt"><font><br></font></div><div style="height:72pt;position:relative;width:100%"><div style="bottom:0;position:absolute;width:100%"><div><font><br></font></div></div></div><div id="i15349b956198436ca89e54c90c36e30b_13"></div><hr style="page-break-after:always"><div style="min-height:72pt;width:100%"><div style="text-align:center"><font><br></font></div></div><div style="text-align:center"><font><br></font></div><div style="-sec-extract:summary;text-align:center"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:120%">EXHIBIT INDEX</font></div><div style="text-align:center"><font><br></font></div><div style="text-align:center"><table style="border-collapse:collapse;display:inline-table;margin-bottom:5pt;vertical-align:text-bottom;width:100.000%"><tr><td style="width:1.0%"></td><td style="width:7.393%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:32.393%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:8.675%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:12.521%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:8.034%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:10.278%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:13.006%"></td><td style="width:0.1%"></td></tr><tr><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="12" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:120%">Incorporated by Reference</font></td><td colspan="3" style="padding:0 1pt"></td></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:120%">Exhibit Number</font></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:120%">Exhibit Description</font></td><td colspan="3" style="border-top:1pt solid #000;padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:120%">Form</font></td><td colspan="3" style="border-top:1pt solid #000;padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:120%">File No.</font></td><td colspan="3" style="border-top:1pt solid #000;padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:120%">Exhibit</font></td><td colspan="3" style="border-top:1pt solid #000;padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:120%">Exhibit Filing Date</font></td><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:120%">Filed&#47;Furnished Herewith</font></td></tr><tr><td colspan="3" style="border-top:1pt solid #000;padding:2px 1pt;text-align:left;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">4.1</font></td><td colspan="3" style="border-top:1pt solid #000;padding:2px 1pt;text-align:left;vertical-align:bottom"><div><font style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%;text-decoration:underline"><a href="https://www.sec.gov/Archives/edgar/data/1274737/000119312519252366/d769261dex31.htm" style="-sec-extract:exhibit;color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%;text-decoration:underline">Amended and Restated Certificate of Incorporation.</a></font></div></td><td colspan="3" style="border-top:1pt solid #000;padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">8-K</font></td><td colspan="3" style="border-top:1pt solid #000;padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">001-39049</font></td><td colspan="3" style="border-top:1pt solid #000;padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">3.1</font></td><td colspan="3" style="border-top:1pt solid #000;padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">9&#47;23&#47;2019</font></td><td colspan="3" style="border-top:1pt solid #000;padding:0 1pt"></td></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">4.2</font></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><div><font style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%;text-decoration:underline"><a href="https://www.sec.gov/Archives/edgar/data/1274737/000127473721000017/ex31-amendedandrestatedbyl.htm" style="-sec-extract:exhibit;color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%;text-decoration:underline">Amended Restated Bylaws.</a></font></div></td><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">8-K</font></td><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">001-39049</font></td><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">3.1</font></td><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">3&#47;22&#47;2021</font></td><td colspan="3" style="padding:0 1pt"></td></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">4.3</font></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><div><font style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%;text-decoration:underline"><a href="https://www.sec.gov/Archives/edgar/data/1274737/000127473723000004/exhibit-exagenxamendmentto.htm" style="-sec-extract:exhibit;color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%;text-decoration:underline">Amendment to Amended and Restated Bylaws, dated January 19, 2023.</a></font></div></td><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">8-K</font></td><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">001-39049</font></td><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">3.1</font></td><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">1&#47;23&#47;2023</font></td><td colspan="3" style="padding:0 1pt"></td></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">4.4</font></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><div><font style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%;text-decoration:underline"><a href="https://www.sec.gov/Archives/edgar/data/1274737/000119312519240403/d692844dex41.htm" style="-sec-extract:exhibit;color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%;text-decoration:underline">Specimen stock certificate evidencing the shares of common stock.</a></font></div></td><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">S-1&#47;A</font></td><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">333-233446</font></td><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">4.1</font></td><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">9&#47;9&#47;2019</font></td><td colspan="3" style="padding:0 1pt"></td></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">5.1</font></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><div><font style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%;text-decoration:underline"><a href="exhibit51-formsx8xopinionm.htm" style="-sec-extract:exhibit;color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%;text-decoration:underline">Opinion of Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C.</a></font></div></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">X</font></td></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">23.1</font></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><div><font style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%;text-decoration:underline"><a href="ex231-bdosx82025consent.htm" style="-sec-extract:exhibit;color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%;text-decoration:underline">Consent of BDO USA, P.C., independent registered public accounting firm.</a></font></div></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">X</font></td></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">23.2</font></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><div><font style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%;text-decoration:underline"><a href="exhibit51-formsx8xopinionm.htm" style="-sec-extract:exhibit;color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%;text-decoration:underline">Consent of Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C. (included in Exhibit 5.1).</a></font></div></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">X</font></td></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">24.1</font></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><div><font style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%;text-decoration:underline"><a href="#i15349b956198436ca89e54c90c36e30b_16" style="-sec-extract:exhibit;color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%;text-decoration:underline">Power of Attorney (see signature page)</a></font></div></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">X</font></td></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">99.1</font></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><div><font style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%;text-decoration:underline"><a href="https://www.sec.gov/Archives/edgar/data/1274737/000119312519240403/d692844dex103.htm" style="-sec-extract:exhibit;color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%;text-decoration:underline">Exagen Inc. 2019 Incentive Award Plan.</a></font></div></td><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">S-1&#47;A</font></td><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">333-233446</font></td><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">10.3</font></td><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">9&#47;9&#47;2019</font></td><td colspan="3" style="padding:0 1pt"></td></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">99.2</font></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><div><font style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%;text-decoration:underline"><a href="https://www.sec.gov/Archives/edgar/data/1274737/000119312519240403/d692844dex104.htm" style="-sec-extract:exhibit;color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%;text-decoration:underline">Form of Option Agreement under Exagen Inc. 2019 Incentive Award Plan.</a></font></div></td><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">S-1&#47;A</font></td><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">333-233446</font></td><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">10.4</font></td><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">9&#47;9&#47;2019</font></td><td colspan="3" style="padding:0 1pt"></td></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">99.3</font></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><div><font style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%;text-decoration:underline"><a href="https://www.sec.gov/Archives/edgar/data/1274737/000127473721000015/ex105-formofrsuagreement20.htm" style="-sec-extract:exhibit;color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%;text-decoration:underline">Form of Restricted Stock Unit Agreement under Exagen Inc. 2019 Incentive Award Plan.</a></font></div></td><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">10-K</font></td><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">001-39049</font></td><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">10.5</font></td><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">3&#47;16&#47;2021</font></td><td colspan="3" style="padding:0 1pt"></td></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">99.4</font></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><div><font style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%;text-decoration:underline"><a href="https://www.sec.gov/Archives/edgar/data/1274737/000119312519240403/d692844dex105.htm" style="-sec-extract:exhibit;color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%;text-decoration:underline">Exagen Inc. 2019 Employee Stock Purchase Plan.</a></font></div></td><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">S-1&#47;A</font></td><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">333-233446</font></td><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">10.5</font></td><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">9&#47;9&#47;2019</font></td><td colspan="3" style="padding:0 1pt"></td></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">107</font></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><div><font style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%;text-decoration:underline"><a href="exhibit107-formsx8calculat.htm" style="-sec-extract:exhibit;color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%;text-decoration:underline">Filing Fee Table.</a></font></div></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">X</font></td></tr></table></div><div style="height:72pt;position:relative;width:100%"><div style="bottom:0;position:absolute;width:100%"><div><font><br></font></div></div></div><div id="i15349b956198436ca89e54c90c36e30b_16"></div><hr style="page-break-after:always"><div style="min-height:72pt;width:100%"><div style="text-align:center"><font><br></font></div></div><div style="text-align:center"><font><br></font></div><div style="text-align:center"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:120%">SIGNATURES</font></div><div style="text-align:center"><font><br></font></div><div style="text-indent:18pt"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">Pursuant to the requirements of the Securities Act of 1933, the Registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-8 and has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Vista, State of California, on May 20, 2025.</font></div><div><font><br></font></div><div><table style="border-collapse:collapse;display:inline-table;margin-bottom:5pt;vertical-align:text-bottom;width:100.000%"><tr><td style="width:1.0%"></td><td style="width:56.762%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:4.854%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:35.084%"></td><td style="width:0.1%"></td></tr><tr><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:120%">EXAGEN INC.</font></td></tr><tr style="height:15pt"><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td></tr><tr><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">by&#58;</font></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">&#47;s&#47; John Aballi</font></td></tr><tr><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="border-top:1pt solid #000;padding:2px 1pt;text-align:left;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">John Aballi</font></td></tr><tr><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">President and Chief Executive Officer</font></td></tr><tr><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">(Principal Executive Officer)</font></td></tr></table></div><div style="text-align:center"><font><br></font></div><div style="text-align:center"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:120%">POWER OF ATTORNEY</font></div><div style="text-align:center"><font><br></font></div><div style="text-indent:18pt"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">Each person whose signature appears below hereby constitutes and appoints John Aballi and Jeffrey G. Black, and each of them singly (with full power to each of them to act alone), his attorneys-in-fact, each with the full power of substitution, for him in any and all capacities, to sign this registration statement, and any amendments thereto (including post-effective amendments), and to file the same, with all exhibits thereto and other documents in connection therewith, with the SEC, hereby ratifying and confirming all that each of said attorneys-in-fact, or his substitute or substitutes, may do or cause to be done by virtue hereof. Pursuant to the requirements of the Securities Act, this registration statement has been signed below by the following persons on behalf of the Registrant and in the capacities and on the dates indicated.</font></div><div style="text-indent:18pt"><font><br></font></div><div style="height:72pt;position:relative;width:100%"><div style="bottom:0;position:absolute;width:100%"><div><font><br></font></div></div></div><hr style="page-break-after:always"><div style="min-height:72pt;width:100%"><div style="text-align:center"><font><br></font></div></div><div style="text-align:center;text-indent:18pt"><table style="border-collapse:collapse;display:inline-table;margin-bottom:5pt;vertical-align:text-bottom;width:100.000%"><tr><td style="width:1.0%"></td><td style="width:4.829%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:20.534%"></td><td style="width:0.1%"></td><td style="width:0.1%"></td><td style="width:0.441%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:48.739%"></td><td style="width:0.1%"></td><td style="width:0.1%"></td><td style="width:0.601%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:20.056%"></td><td style="width:0.1%"></td></tr><tr><td colspan="6" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:120%">Signature</font></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:120%">Title</font></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:120%">Date</font></td></tr><tr style="height:9pt"><td colspan="3" style="border-top:1pt solid #000;padding:0 1pt"></td><td colspan="3" style="border-top:1pt solid #000;padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="border-top:1pt solid #000;padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="border-top:1pt solid #000;padding:0 1pt"></td></tr><tr><td colspan="6" style="border-bottom:1pt solid #000;padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">&#47;s&#47; John Aballi</font></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">President, Chief Executive Officer and Director</font></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">May 20, 2025</font></td></tr><tr><td colspan="6" style="border-top:1pt solid #000;padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">John Aballi</font></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">(Principal Executive Officer)</font></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td></tr><tr style="height:9pt"><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td></tr><tr><td colspan="6" style="border-bottom:1pt solid #000;padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">&#47;s&#47; Jeffrey G. Black</font></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">Chief Financial Officer and Corporate Secretary</font></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">May 20, 2025</font></td></tr><tr><td colspan="6" style="border-top:1pt solid #000;padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">Jeffrey G. Black</font></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">(Principal Financial and Accounting Officer)</font></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td></tr><tr style="height:9pt"><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td></tr><tr><td colspan="6" style="border-bottom:1pt solid #000;padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">&#47;s&#47; Tina S. Nova, Ph.D.</font></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">Executive Chairman of the Board of Directors</font></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">May 20, 2025</font></td></tr><tr><td colspan="6" style="border-top:1pt solid #000;padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">Tina S. Nova, Ph.D.</font></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td></tr><tr style="height:9pt"><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td></tr><tr><td colspan="6" style="border-bottom:1pt solid #000;padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">&#47;s&#47; Ana Hooker</font></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">Director</font></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">May 20, 2025</font></td></tr><tr><td colspan="6" style="border-top:1pt solid #000;padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">Ana Hooker</font></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td></tr><tr style="height:9pt"><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td></tr><tr><td colspan="6" style="border-bottom:1pt solid #000;padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">&#47;s&#47; Scott Kahn, Ph.D.</font></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">Director</font></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">May 20, 2025</font></td></tr><tr><td colspan="6" style="border-top:1pt solid #000;padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">Scott Kahn, Ph.D.</font></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td></tr><tr style="height:9pt"><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td></tr><tr><td colspan="6" style="border-bottom:1pt solid #000;padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">&#47;s&#47; 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Document
As filed with the Securities and Exchange Commission on May 20, 2025
Registration No. 333-
UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
FORM S-8
REGISTRATION STATEMENT UNDER
THE SECURITIES ACT OF 1933
EXAGEN INC.
(Exact name of registrant as specified in its charter)
Delaware
20-0434866
(State or other jurisdiction of
incorporation or organization)
(I.R.S. Employer
Identification No.)
1261 Liberty Way
Vista, California 92081
(Address of principal executive offices) (Zip code)
Exagen Inc. 2019 Incentive Award Plan
Exagen Inc. 2019 Employee Stock Purchase Plan
(Full title of the plans)
John Aballi
President and Chief Executive Officer
Exagen Inc.
1261 Liberty Way
Vista, California 92081
(760) 560-1501
(Name, address, and telephone number, including area code, of agent for service)
Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company or an emerging growth company. See the definitions of "large accelerated filer," "accelerated filer," "smaller reporting company," and "emerging growth company" in Rule 12b-2 of the Exchange Act.
Large accelerated filer
☐
Accelerated filer
☐
Non-accelerated filer
☒
Smaller reporting company
☒
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 7(a)(2)(B) of the Securities Act.
☐
EXPLANATORY NOTE
This Registration Statement on Form S-8 is being filed with the Securities and Exchange Commission (the "SEC") for the purpose of registering an additional 882,016 shares of common stock of Exagen Inc. (the "Registrant") issuable or which may become issuable under the Exagen Inc. 2019 Incentive Award Plan (the "2019 Plan") and the Exagen Inc. 2019 Employee Stock Purchase Plan (the "2019 ESPP") pursuant to the evergreen provision of such plans.
Pursuant to General Instruction E on Form S-8, the contents of the prior registration statements on Form S-8, File Nos. 333-233878, 333-256014, 333-264867, 333-272038 and 333-279356, previously filed with respect to the 2019 Plan and 2019 ESPP, are incorporated into this Registration Statement by reference to the extent not modified or superseded hereby or by any subsequently filed document, which is incorporated by reference herein or therein.
PART I
INFORMATION REQUIRED IN THE SECTION 10(a) PROSPECTUS
The documents containing the information specified in Part I of Form S-8 will be sent or given to participants as specified by Rule 428(b)(1) of the Securities Act of 1933, as amended (the "Securities Act"). These documents and the documents incorporated by reference into this Registration Statement pursuant to Item 3 of Part II of this Registration Statement, taken together, constitute a prospectus that meets the requirements of Section 10(a) of the Securities Act.
PART II
INFORMATION REQUIRED IN THE REGISTRATION STATEMENT
In this Registration Statement, Exagen Inc. is sometimes referred to as "Registrant," "we," "us" or "our."
Item 3. Incorporation of Documents by Reference
The Securities and Exchange Commission allows us to "incorporate by reference" the information we file with them, which means that we can disclose important information to you by referring you to those documents. The information incorporated by reference is considered to be part of this Registration Statement, and later information filed with the SEC will update and supersede this information. We hereby incorporate by reference into this Registration Statement the following documents previously filed with the SEC:
•
The Registrant's Annual Report on Form 10-K for the year ended December 31, 2024, filed with the SEC on
March 11, 2025
, including the information incorporated by reference into our Annual Report on Form 10-K from our definitive proxy statement for our 2025 Annual Meeting of Stockholders, filed with the SEC on
April 30, 2025
;
•
The Registrant's Quarterly Report on Form 10-Q for the quarter ended March 31, 2025, filed with the SEC on
May 5, 2025
;
•
The Registrant's Current Reports on Form 8-K filed with the SEC on
January 13, 2025
,
March 11, 2025
,
April 28, 2025
,
May 5, 2025
,
May 8, 2025
and
M
ay 9, 2025
; and
•
The description of the Registrant's common stock set forth in the Registrant's registration statement on Form 8-A12B (Registration No. 001-39049), filed by the Registrant with the SEC under Section 12(b) of the Securities Exchange Act of 1934, as amended (the "Exchange Act"), on
September 13, 2019
, including any amendments or reports filed for the purpose of updating such description.
In addition, all documents filed by the Registrant pursuant to Section 13(a), 13(c), 14 or 15(d) of the Exchange Act subsequent to the filing of this registration statement and prior to the filing of a post-effective amendment which indicates that all securities offered hereby have been sold or which de-registers all securities then remaining unsold shall be deemed to be incorporated by reference into this registration statement and to be a part hereof from the date of filing such documents, except as to specific sections of such statements as set forth therein. Any statement contained in a document incorporated or deemed to be incorporated by reference herein shall be deemed to be modified or superseded for purposes of this registration statement to the extent that a statement contained herein or in any other subsequently filed document which also is incorporated or deemed to be incorporated by reference herein modifies or supersedes such statement. Any statement contained herein shall be deemed to be modified or superseded for purposes of this registration statement to the extent that a statement contained in any subsequently filed document which also is incorporated or deemed to be incorporated by reference herein modifies or supersedes such statement. Any such statement so modified or superseded shall not be deemed, except as so modified or superseded, to constitute a part of this registration statement.
Under no circumstances shall any information furnished under Item 2.02 or 7.01 of Form 8-K be deemed incorporated herein by reference unless such Form 8-K expressly provides to the contrary.
EXHIBIT INDEX
Incorporated by Reference
Exhibit Number
Exhibit Description
Form
File No.
Exhibit
Exhibit Filing Date
Filed/Furnished Herewith
4.1
Amended and Restated Certificate of Incorporation.
8-K
001-39049
3.1
9/23/2019
4.2
Amended Restated Bylaws.
8-K
001-39049
3.1
3/22/2021
4.3
Amendment to Amended and Restated Bylaws, dated January 19, 2023.
8-K
001-39049
3.1
1/23/2023
4.4
Specimen stock certificate evidencing the shares of common stock.
S-1/A
333-233446
4.1
9/9/2019
5.1
Opinion of Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C.
X
23.1
Consent of BDO USA, P.C., independent registered public accounting firm.
X
23.2
Consent of Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C. (included in Exhibit 5.1).
X
24.1
Power of Attorney (see signature page)
X
99.1
Exagen Inc. 2019 Incentive Award Plan.
S-1/A
333-233446
10.3
9/9/2019
99.2
Form of Option Agreement under Exagen Inc. 2019 Incentive Award Plan.
S-1/A
333-233446
10.4
9/9/2019
99.3
Form of Restricted Stock Unit Agreement under Exagen Inc. 2019 Incentive Award Plan.
10-K
001-39049
10.5
3/16/2021
99.4
Exagen Inc. 2019 Employee Stock Purchase Plan.
S-1/A
333-233446
10.5
9/9/2019
107
Filing Fee Table.
X
SIGNATURES
Pursuant to the requirements of the Securities Act of 1933, the Registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-8 and has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Vista, State of California, on May 20, 2025.
EXAGEN INC.
by:
/s/ John Aballi
John Aballi
President and Chief Executive Officer
(Principal Executive Officer)
POWER OF ATTORNEY
Each person whose signature appears below hereby constitutes and appoints John Aballi and Jeffrey G. Black, and each of them singly (with full power to each of them to act alone), his attorneys-in-fact, each with the full power of substitution, for him in any and all capacities, to sign this registration statement, and any amendments thereto (including post-effective amendments), and to file the same, with all exhibits thereto and other documents in connection therewith, with the SEC, hereby ratifying and confirming all that each of said attorneys-in-fact, or his substitute or substitutes, may do or cause to be done by virtue hereof. Pursuant to the requirements of the Securities Act, this registration statement has been signed below by the following persons on behalf of the Registrant and in the capacities and on the dates indicated.
Signature
Title
Date
/s/ John Aballi
President, Chief Executive Officer and Director
May 20, 2025
John Aballi
(Principal Executive Officer)
/s/ Jeffrey G. Black
Chief Financial Officer and Corporate Secretary
May 20, 2025
Jeffrey G. Black
(Principal Financial and Accounting Officer)
/s/ Tina S. Nova, Ph.D.
Executive Chairman of the Board of Directors
May 20, 2025
Tina S. Nova, Ph.D.
/s/ Ana Hooker
Director
May 20, 2025
Ana Hooker
/s/ Scott Kahn, Ph.D.
Director
May 20, 2025
Scott Kahn, Ph.D.
/s/ Paul Kim
Director
May 20, 2025
Paul Kim
/s/ Bruce C. Robertson, Ph.D.
Director
May 20, 2025
Bruce C. Robertson, Ph.D.
/s/ Frank Stokes
Director
May 20, 2025
Frank Stokes