SIGMA LABS, INC.
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<TYPE>EX-10.28
<SEQUENCE>4
<FILENAME>ex10-28.htm
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<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: right; text-indent: 0.5in"><FONT STYLE="font-family: Times New Roman, Times, Serif; font-size: 10pt"><B>Exhibit
10.28</B></FONT></P>

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<P STYLE="font: 10pt Times New Roman, Times, Serif; margin-top: 0; margin-bottom: 0; text-align: center"><FONT STYLE="font-family: Times New Roman, Times, Serif; font-size: 10pt; font-weight: normal"><U>AMENDMENT
TO EMPLOYMENT AGREEMENT</U></FONT></P>

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<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify; text-indent: 0.5in"><FONT STYLE="font-family: Times New Roman, Times, Serif; font-size: 10pt">This
Amendment (&ldquo;Amendment&rdquo;) to the employment letter agreement by and between Sigma Labs, Inc. (the &ldquo;Company&rdquo;) and
Jacob Brunsberg (&ldquo;Brunsberg&rdquo; or &ldquo;you&rdquo;), effective as of September 20, 2021 (the &ldquo;Agreement&rdquo;), is
made effective as of February 16, 2022 (the &ldquo;Effective Date&rdquo;).</FONT></P>

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<P STYLE="font: 10pt Times New Roman, Times, Serif; margin-top: 0; margin-bottom: 0; text-align: center"><FONT STYLE="font-family: Times New Roman, Times, Serif; font-size: 10pt">RECITAL</FONT></P>

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<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify; text-indent: 0.5in"><FONT STYLE="font-family: Times New Roman, Times, Serif; font-size: 10pt">The
Company and you desire to amend the Agreement upon the terms set forth in this Amendment.</FONT></P>

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<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify; text-indent: 0.5in"><FONT STYLE="font-family: Times New Roman, Times, Serif; font-size: 10pt">NOW,
THEREFORE, in consideration of the foregoing and other good and valuable consideration, the receipt and sufficiency of which hereby are
acknowledged, the Company and Brunsberg hereby agree as follows:</FONT></P>

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<P STYLE="font: 10pt Times New Roman, Times, Serif; margin-top: 0; margin-bottom: 0; text-align: center"><FONT STYLE="font-family: Times New Roman, Times, Serif; font-size: 10pt">AMENDMENT</FONT></P>

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<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"><FONT STYLE="font-family: Times New Roman, Times, Serif; font-size: 10pt">1.
<U>Definitions</U>. Terms not otherwise defined in this Amendment shall have the meanings attributed to such terms in the Agreement.
References in the Agreement and in this Amendment to this &ldquo;Agreement&rdquo; mean the Agreement as amended by this Amendment and
as further amended from time to time as provided in the Agreement.</FONT></P>

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<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"><FONT STYLE="font-family: Times New Roman, Times, Serif; font-size: 10pt">2.
<U>Amendments</U>.</FONT></P>

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<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify; text-indent: 0.5in"><FONT STYLE="font-family: Times New Roman, Times, Serif; font-size: 10pt">2.1
Section 1 of the Agreement shall be deleted and replaced in its entirety with the following:</FONT></P>

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<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify; text-indent: 1in"><FONT STYLE="font-family: Times New Roman, Times, Serif; font-size: 10pt">&ldquo;1.
<U>Position; Reporting; Duties, Responsibilities and Authority; Principal Business Office</U>: Effective as the Effective Date, you shall
serve as President and Chief Operating Officer of the Company. You shall report on a day-to-day basis directly to and shall be subject
to the supervision and direction of, the Company&rsquo;s Chief Executive Officer.</FONT></P>

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<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify; text-indent: 0.5in"><FONT STYLE="font-family: Times New Roman, Times, Serif; font-size: 10pt">You
shall perform your duties hereunder during normal business hours and at all other times and locations necessary for you to carry out
your duties. You shall devote substantially all of your business time to the Company and shall perform such duties as are customarily
performed by individuals acting as President and Chief Operating Officer of a public company of a similar size as the Company, and other
such duties as you may be assigned from time to time by the Chief Executive Officer or the Board of Directors of the Company. You shall
at all times be subject to, observe and carry out such reasonable employment-related rules, regulations and policies as the Company&rsquo;s
Board of Directors or Chief Executive Officer may from time to time establish for the Company&rsquo;s employees, including, without limitation,
the Company&rsquo;s Employee Handbook, Insider Trading Policy and Code of Ethics and Business Conduct.</FONT></P>

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<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify; text-indent: 0.5in"><FONT STYLE="font-family: Times New Roman, Times, Serif; font-size: 10pt">Without
limiting the foregoing, your responsibilities shall include those matters set forth on Exhibit A hereto. Without restricting any requirement
that you engage in reasonable business-related travel, including travel to the Company&rsquo;s principal business office located in Santa
Fe, NM, the principal location in which you shall be required to perform your duties and responsibilities shall be your home-based office
located at 2724 Ewing Ave S., Minneapolis, MN 55416.&rdquo;</FONT></P>

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<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify; text-indent: 0.5in"><FONT STYLE="font-family: Times New Roman, Times, Serif; font-size: 10pt">2.2
The Base Salary referenced in Section 3(a) of the Agreement shall be changed from $200,000 to $250,000 effective as of the Effective
Date.</FONT></P>

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<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"><FONT STYLE="font-family: Times New Roman, Times, Serif; font-size: 10pt">3.
<U>No Other Changes to the Agreement; Miscellaneous</U>. Except as expressly amended by this Amendment, the terms and conditions of the
Agreement shall remain in full force and effect. This Amendment may be executed in counterparts, each of which shall be deemed an original
document, and all of which, taken together, shall be deemed and all constitute one and the same instrument.</FONT></P>

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<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify; text-indent: 0.5in"><FONT STYLE="font-family: Times New Roman, Times, Serif; font-size: 10pt">IN
WITNESS WHEREOF, the Company and Brunsberg have executed and delivered this Amendment as of the Effective Date.</FONT></P>

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    <TD COLSPAN="2" STYLE="font: 10pt Times New Roman, Times, Serif"><FONT STYLE="font-family: Times New Roman, Times, Serif; font-size: 10pt">Sigma Labs, Inc.</FONT></TD>
    <TD STYLE="font: 10pt Times New Roman, Times, Serif"><FONT STYLE="font-family: Times New Roman, Times, Serif; font-size: 10pt">&nbsp;</FONT></TD>
    <TD COLSPAN="2" STYLE="font: 10pt Times New Roman, Times, Serif"><FONT STYLE="font-family: Times New Roman, Times, Serif; font-size: 10pt">Brunsberg</FONT></TD></TR>
  <TR STYLE="font: 10pt Times New Roman, Times, Serif; vertical-align: top">
    <TD STYLE="font: 10pt Times New Roman, Times, Serif; width: 5%"><FONT STYLE="font-family: Times New Roman, Times, Serif; font-size: 10pt">&nbsp;</FONT></TD>
    <TD STYLE="font: 10pt Times New Roman, Times, Serif; width: 44%; text-align: justify"><FONT STYLE="font-family: Times New Roman, Times, Serif; font-size: 10pt">&nbsp;</FONT></TD>
    <TD STYLE="font: 10pt Times New Roman, Times, Serif; width: 2%"><FONT STYLE="font-family: Times New Roman, Times, Serif; font-size: 10pt">&nbsp;</FONT></TD>
    <TD STYLE="font: 10pt Times New Roman, Times, Serif; width: 5%"><FONT STYLE="font-family: Times New Roman, Times, Serif; font-size: 10pt">&nbsp;</FONT></TD>
    <TD STYLE="font: 10pt Times New Roman, Times, Serif; width: 44%"><FONT STYLE="font-family: Times New Roman, Times, Serif; font-size: 10pt">&nbsp;</FONT></TD></TR>
  <TR STYLE="font: 10pt Times New Roman, Times, Serif; vertical-align: top">
    <TD STYLE="font: 10pt Times New Roman, Times, Serif"><FONT STYLE="font-family: Times New Roman, Times, Serif; font-size: 10pt">By:</FONT></TD>
    <TD STYLE="border-bottom: black 1.5pt solid; font: 10pt Times New Roman, Times, Serif"><FONT STYLE="font-family: Times New Roman, Times, Serif; font-size: 10pt"><I>/s/
    Mark K. Ruport</I></FONT></TD>
    <TD STYLE="font: 10pt Times New Roman, Times, Serif"><FONT STYLE="font-family: Times New Roman, Times, Serif; font-size: 10pt">&nbsp;</FONT></TD>
    <TD STYLE="font: 10pt Times New Roman, Times, Serif"><FONT STYLE="font-family: Times New Roman, Times, Serif; font-size: 10pt">By</FONT></TD>
    <TD STYLE="border-bottom: black 1.5pt solid; font: 10pt Times New Roman, Times, Serif"><FONT STYLE="font-family: Times New Roman, Times, Serif; font-size: 10pt"><I>/s/
    Jacob Brunsberg</I></FONT></TD></TR>
  <TR STYLE="font: 10pt Times New Roman, Times, Serif; vertical-align: top">
    <TD STYLE="font: 10pt Times New Roman, Times, Serif"><P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"><FONT STYLE="font-family: Times New Roman, Times, Serif; font-size: 10pt">Name:</FONT></P>
    <P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0"><FONT STYLE="font-family: Times New Roman, Times, Serif; font-size: 10pt">Title:</FONT></P></TD>
    <TD STYLE="font: 10pt Times New Roman, Times, Serif"><P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"><FONT STYLE="font-family: Times New Roman, Times, Serif; font-size: 10pt">Mark
                                            K. Ruport</FONT></P>
    <P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0"><FONT STYLE="font-family: Times New Roman, Times, Serif; font-size: 10pt">Chief
    Executive Officer</FONT></P></TD>
    <TD STYLE="font: 10pt Times New Roman, Times, Serif"><FONT STYLE="font-family: Times New Roman, Times, Serif; font-size: 10pt">&nbsp;</FONT></TD>
    <TD STYLE="font: 10pt Times New Roman, Times, Serif"><FONT STYLE="font-family: Times New Roman, Times, Serif; font-size: 10pt">Name:</FONT></TD>
    <TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: justify"><FONT STYLE="font-family: Times New Roman, Times, Serif; font-size: 10pt">Jacob Brunsberg</FONT></TD></TR>
  </TABLE>
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