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  <title>8-K</title>
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  <div style="display:none;"><ix:header><ix:hidden><ix:nonNumeric id="F_3bf6d5ad-8ef1-4236-aa7a-57050140cfb2" name="dei:AmendmentFlag" contextRef="C_0b02fbbc-b6dd-4e8a-8fd8-6ba51a222673">false</ix:nonNumeric><ix:nonNumeric id="F_19e01a19-2086-4df2-bba8-48e34a0bfd36" name="dei:EntityCentralIndexKey" contextRef="C_0b02fbbc-b6dd-4e8a-8fd8-6ba51a222673">0000926282</ix:nonNumeric></ix:hidden><ix:references><link:schemaRef xlink:type="simple" xlink:href="adtn-20240506.xsd"/></ix:references><ix:resources><xbrli:context id="C_0b02fbbc-b6dd-4e8a-8fd8-6ba51a222673"><xbrli:entity><xbrli:identifier scheme="http://www.sec.gov/CIK">0000926282</xbrli:identifier></xbrli:entity><xbrli:period><xbrli:startDate>2024-05-06</xbrli:startDate><xbrli:endDate>2024-05-06</xbrli:endDate></xbrli:period></xbrli:context></ix:resources></ix:header></div>
  <div style="padding-top:0.5in;min-height:0.5in;box-sizing:border-box;"><p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:0;text-align:left;"><span style="white-space:pre-wrap;font-size:11pt;font-family:'Calibri',sans-serif;min-width:fit-content;">&#160;</span></p></div>
  <p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:12pt;text-align:center;"><span style="color:#000000;white-space:pre-wrap;font-weight:bold;font-size:10pt;font-family:Times New Roman;min-width:fit-content;"> </span><span style="color:#000000;white-space:pre-wrap;font-weight:bold;font-size:18pt;font-family:Times New Roman;min-width:fit-content;">UNITED STATES</span></p>
  <p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:0;text-align:center;"><span style="color:#000000;white-space:pre-wrap;font-weight:bold;font-size:18pt;font-family:Times New Roman;min-width:fit-content;">SECURITIES AND EXCHANGE COMMISSION</span></p>
  <p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:0;text-align:center;"><span style="color:#000000;white-space:pre-wrap;font-weight:bold;font-size:12pt;font-family:Times New Roman;min-width:fit-content;">WASHINGTON, D.C. 20549</span><span style="color:#000000;white-space:pre-wrap;font-weight:bold;font-size:12pt;font-family:Times New Roman;min-width:fit-content;"> </span></p>
  <p style="margin-left:40%;padding-bottom:1pt;font-size:10pt;margin-top:9pt;font-family:Times New Roman;margin-bottom:0;border-bottom:1pt solid;margin-right:40%;text-align:center;"><span style="color:#000000;white-space:pre-wrap;font-size:6pt;font-family:Times New Roman;min-width:fit-content;"> </span></p>
  <p style="font-size:10pt;margin-top:9pt;font-family:Times New Roman;margin-bottom:0;text-align:center;"><span style="color:#000000;white-space:pre-wrap;font-weight:bold;font-size:18pt;font-family:Times New Roman;min-width:fit-content;">FORM </span><span style="font-size:18pt;font-family:Times New Roman;"><ix:nonNumeric id="F_ea74d1f9-6335-4798-abfe-9f0c8c4da8fc" contextRef="C_0b02fbbc-b6dd-4e8a-8fd8-6ba51a222673" name="dei:DocumentType"><span style="color:#000000;white-space:pre-wrap;font-weight:bold;font-size:18pt;font-family:Times New Roman;min-width:fit-content;">8-K</span></ix:nonNumeric></span><span style="color:#000000;white-space:pre-wrap;font-weight:bold;font-size:18pt;font-family:Times New Roman;min-width:fit-content;"> </span></p>
  <p style="margin-left:40%;padding-bottom:1pt;font-size:10pt;margin-top:9pt;font-family:Times New Roman;margin-bottom:0;border-bottom:1pt solid;margin-right:40%;text-align:center;"><span style="color:#000000;white-space:pre-wrap;font-size:6pt;font-family:Times New Roman;min-width:fit-content;"> </span></p>
  <p style="font-size:10pt;margin-top:9pt;font-family:Times New Roman;margin-bottom:0;text-align:center;"><span style="color:#000000;white-space:pre-wrap;font-weight:bold;font-size:12pt;font-family:Times New Roman;min-width:fit-content;">CURRENT REPORT</span><span style="color:#000000;white-space:pre-wrap;font-weight:bold;font-size:12pt;font-family:Times New Roman;min-width:fit-content;"> </span></p>
  <p style="font-size:10pt;margin-top:9pt;font-family:Times New Roman;margin-bottom:0;text-align:center;"><span style="color:#000000;white-space:pre-wrap;font-weight:bold;font-size:12pt;font-family:Times New Roman;min-width:fit-content;">Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934</span><span style="color:#000000;white-space:pre-wrap;font-weight:bold;font-size:12pt;font-family:Times New Roman;min-width:fit-content;"> </span></p>
  <p style="font-size:10pt;margin-top:9pt;font-family:Times New Roman;margin-bottom:0;text-align:center;"><span style="color:#000000;white-space:pre-wrap;font-weight:bold;font-size:10pt;font-family:Times New Roman;min-width:fit-content;">Date of Report (Date of earliest event reported): </span><span style="font-size:10pt;font-family:Times New Roman;"><ix:nonNumeric id="F_2fc1e4e8-c5ba-4f67-8534-89e9929038f2" contextRef="C_0b02fbbc-b6dd-4e8a-8fd8-6ba51a222673" name="dei:DocumentPeriodEndDate" format="ixt:date-monthname-day-year-en"><span style="color:#000000;white-space:pre-wrap;font-weight:bold;font-size:10pt;font-family:Times New Roman;min-width:fit-content;">May 6, 2024</span></ix:nonNumeric></span><span style="color:#000000;white-space:pre-wrap;font-weight:bold;font-size:10pt;font-family:Times New Roman;min-width:fit-content;"> </span></p>
  <p style="margin-left:40%;padding-bottom:1pt;font-size:10pt;margin-top:9pt;font-family:Times New Roman;margin-bottom:0;border-bottom:1pt solid;margin-right:40%;text-align:center;"><span style="color:#000000;white-space:pre-wrap;font-size:6pt;font-family:Times New Roman;min-width:fit-content;"> </span></p>
  <p style="font-size:10pt;margin-top:9pt;font-family:Times New Roman;margin-bottom:0;text-align:center;"><span style="font-size:24pt;font-family:Times New Roman;"><ix:nonNumeric id="F_f292f4c5-a2d4-4916-a94e-2326b2fa690a" contextRef="C_0b02fbbc-b6dd-4e8a-8fd8-6ba51a222673" name="dei:EntityRegistrantName"><span style="color:#000000;white-space:pre-wrap;font-weight:bold;font-size:24pt;font-family:Times New Roman;min-width:fit-content;">ADTRAN Holdings, Inc.</span></ix:nonNumeric></span><span style="color:#000000;white-space:pre-wrap;font-weight:bold;font-size:24pt;font-family:Times New Roman;min-width:fit-content;"> </span></p>
  <p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:0;text-align:center;"><span style="color:#000000;white-space:pre-wrap;font-weight:bold;font-size:8pt;font-family:Times New Roman;min-width:fit-content;">(Exact name of Registrant as Specified in Its Charter)</span><span style="color:#000000;white-space:pre-wrap;font-weight:bold;font-size:8pt;font-family:Times New Roman;min-width:fit-content;"> </span></p>
  <p style="margin-left:40%;padding-bottom:1pt;font-size:10pt;margin-top:9pt;font-family:Times New Roman;margin-bottom:0;border-bottom:1pt solid;margin-right:40%;text-align:center;"><span style="color:#000000;white-space:pre-wrap;font-size:6pt;font-family:Times New Roman;min-width:fit-content;"> </span></p>
  <p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:0;text-align:justify;"><span style="color:#000000;white-space:pre-wrap;font-size:9pt;font-family:Times New Roman;min-width:fit-content;"> </span></p>
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    <td style="vertical-align:bottom;padding-right:0.01in;"><p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:0;text-align:center;"><span><ix:nonNumeric id="F_5cf0c475-2bb9-4cc4-bdfc-b3ece726402d" contextRef="C_0b02fbbc-b6dd-4e8a-8fd8-6ba51a222673" name="dei:EntityIncorporationStateCountryCode" format="ixt-sec:stateprovnameen"><span style="color:#000000;white-space:pre-wrap;font-weight:bold;min-width:fit-content;">Delaware</span></ix:nonNumeric></span></p></td>
    <td style="vertical-align:bottom;padding-right:0.01in;"><p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:0;text-align:center;"><span><ix:nonNumeric id="F_d75607b6-442a-43f9-bab3-6c24a8bab12e" contextRef="C_0b02fbbc-b6dd-4e8a-8fd8-6ba51a222673" name="dei:EntityFileNumber"><span style="color:#000000;white-space:pre-wrap;font-weight:bold;min-width:fit-content;">001-41446</span></ix:nonNumeric></span></p></td>
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    <td style="vertical-align:bottom;padding-right:0.01in;"><p style="font-size:8pt;margin-top:0;font-family:Times New Roman;margin-bottom:0;text-align:center;"><span style="color:#000000;white-space:pre-wrap;font-weight:bold;min-width:fit-content;">(State or Other Jurisdiction</span></p><p style="font-size:8pt;margin-top:0;font-family:Times New Roman;margin-bottom:0.75pt;text-align:center;"><span style="color:#000000;white-space:pre-wrap;font-weight:bold;min-width:fit-content;">of Incorporation)</span></p></td>
    <td style="vertical-align:bottom;padding-right:0.01in;"><p style="font-size:8pt;margin-top:0;font-family:Times New Roman;margin-bottom:0;text-align:center;"><span style="color:#000000;white-space:pre-wrap;font-weight:bold;min-width:fit-content;">(Commission File Number)</span></p></td>
    <td style="vertical-align:bottom;padding-right:0.01in;"><p style="font-size:8pt;margin-top:0;font-family:Times New Roman;margin-bottom:0;text-align:center;"><span style="color:#000000;white-space:pre-wrap;font-weight:bold;min-width:fit-content;">(IRS Employer</span></p><p style="font-size:8pt;margin-top:0;font-family:Times New Roman;margin-bottom:0.75pt;text-align:center;"><span style="color:#000000;white-space:pre-wrap;font-weight:bold;min-width:fit-content;">Identification No.)</span></p></td>
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    <td style="vertical-align:bottom;padding-right:0.01in;"><p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:0;text-align:justify;"><span style="white-space:pre-wrap;min-width:fit-content;">&#160;</span></p></td>
    <td style="vertical-align:bottom;padding-right:0.01in;"><p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:0;text-align:justify;"><span style="white-space:pre-wrap;min-width:fit-content;">&#160;</span></p></td>
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    <td style="vertical-align:bottom;padding-right:0.01in;text-align:left;"><p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:0.75pt;text-align:center;"><span><ix:nonNumeric id="F_f6ff6966-e69a-4e5b-86f0-6045b61e2688" contextRef="C_0b02fbbc-b6dd-4e8a-8fd8-6ba51a222673" name="dei:EntityAddressAddressLine1"><span style="color:#000000;white-space:pre-wrap;font-weight:bold;min-width:fit-content;">901 Explorer Boulevard</span></ix:nonNumeric></span></p><p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:0.75pt;text-align:center;"><span><ix:nonNumeric id="F_3d639862-987f-40d0-a2dc-604051658d86" contextRef="C_0b02fbbc-b6dd-4e8a-8fd8-6ba51a222673" name="dei:EntityAddressCityOrTown"><span style="color:#000000;white-space:pre-wrap;font-weight:bold;min-width:fit-content;">Huntsville</span></ix:nonNumeric></span><span style="color:#000000;white-space:pre-wrap;font-weight:bold;min-width:fit-content;">, </span><span><ix:nonNumeric id="F_7e017f82-d451-431a-80bc-b1b7048aabf5" contextRef="C_0b02fbbc-b6dd-4e8a-8fd8-6ba51a222673" name="dei:EntityAddressStateOrProvince" format="ixt-sec:stateprovnameen"><span style="color:#000000;white-space:pre-wrap;font-weight:bold;min-width:fit-content;">Alabama</span></ix:nonNumeric></span></p></td>
    <td style="padding-left:0.1in;vertical-align:bottom;text-align:right;"><p style="font-size:4pt;margin-top:0;font-family:Times New Roman;margin-bottom:0;text-align:justify;"><span style="color:#000000;white-space:pre-wrap;min-width:fit-content;"> </span></p></td>
    <td style="vertical-align:bottom;padding-right:0.01in;text-align:left;"><p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:0;text-align:center;"><span><ix:nonNumeric id="F_6cf254c6-e04c-46c2-ad0c-731a8184c1fa" contextRef="C_0b02fbbc-b6dd-4e8a-8fd8-6ba51a222673" name="dei:EntityAddressPostalZipCode"><span style="color:#000000;white-space:pre-wrap;font-weight:bold;min-width:fit-content;">35806-2807</span></ix:nonNumeric></span></p></td>
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    <td style="vertical-align:bottom;padding-right:0.01in;text-align:left;"><p style="font-size:8pt;margin-top:0;font-family:Times New Roman;margin-bottom:0;text-align:center;"><span style="color:#000000;white-space:pre-wrap;font-weight:bold;min-width:fit-content;">(Address of Principal Executive Offices)</span></p></td>
    <td style="padding-left:0.1in;vertical-align:bottom;text-align:right;"><p style="font-size:4pt;margin-top:0;font-family:Times New Roman;margin-bottom:0;text-align:justify;"><span style="color:#000000;white-space:pre-wrap;min-width:fit-content;"> </span></p></td>
    <td style="vertical-align:bottom;padding-right:0.01in;text-align:left;"><p style="font-size:8pt;margin-top:0;font-family:Times New Roman;margin-bottom:0;text-align:center;"><span style="color:#000000;white-space:pre-wrap;font-weight:bold;min-width:fit-content;">(Zip Code)</span></p></td>
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  <p style="font-size:10pt;margin-top:9pt;font-family:Times New Roman;margin-bottom:0;text-align:center;"><span style="color:#000000;white-space:pre-wrap;font-weight:bold;font-size:10pt;font-family:Times New Roman;min-width:fit-content;">Registrant&#8217;s Telephone Number, Including Area Code: </span><span style="font-size:10pt;font-family:Times New Roman;"><ix:nonNumeric id="F_d3712b64-11a7-4676-b139-62c19bba92fa" contextRef="C_0b02fbbc-b6dd-4e8a-8fd8-6ba51a222673" name="dei:CityAreaCode"><span style="color:#000000;white-space:pre-wrap;font-weight:bold;font-size:10pt;font-family:Times New Roman;min-width:fit-content;">(256)</span></ix:nonNumeric></span><span style="color:#000000;white-space:pre-wrap;font-weight:bold;font-size:10pt;font-family:Times New Roman;min-width:fit-content;"> </span><span style="font-size:10pt;font-family:Times New Roman;"><ix:nonNumeric id="F_bffa5592-0be0-41e3-b0e4-a64622c45e96" contextRef="C_0b02fbbc-b6dd-4e8a-8fd8-6ba51a222673" name="dei:LocalPhoneNumber"><span style="color:#000000;white-space:pre-wrap;font-weight:bold;font-size:10pt;font-family:Times New Roman;min-width:fit-content;">963-8000</span></ix:nonNumeric></span><span style="color:#000000;white-space:pre-wrap;font-weight:bold;font-size:10pt;font-family:Times New Roman;min-width:fit-content;"> </span></p>
  <p style="font-size:10pt;margin-top:9pt;font-family:Times New Roman;margin-bottom:0;text-align:center;"><span style="color:#000000;white-space:pre-wrap;font-weight:bold;font-size:10pt;font-family:Times New Roman;min-width:fit-content;">Not Applicable</span></p>
  <p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:0;text-align:center;"><span style="color:#000000;white-space:pre-wrap;font-weight:bold;font-size:8pt;font-family:Times New Roman;min-width:fit-content;">(Former Name or Former Address, if Changed Since Last Report)</span><span style="color:#000000;white-space:pre-wrap;font-weight:bold;font-size:8pt;font-family:Times New Roman;min-width:fit-content;"> </span></p>
  <p style="margin-left:40%;padding-bottom:1pt;font-size:10pt;margin-top:9pt;font-family:Times New Roman;margin-bottom:0;border-bottom:1pt solid;margin-right:40%;text-align:center;"><span style="color:#000000;white-space:pre-wrap;font-size:6pt;font-family:Times New Roman;min-width:fit-content;"> </span></p>
  <p style="font-size:10pt;margin-top:8pt;font-family:Times New Roman;margin-bottom:0;text-align:justify;"><span style="color:#000000;white-space:pre-wrap;font-size:10pt;font-family:Times New Roman;min-width:fit-content;">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 Instructions A.2. below):</span><span style="color:#000000;white-space:pre-wrap;font-size:10pt;font-family:Times New Roman;min-width:fit-content;"> </span></p>
  <p style="text-indent:-4.749%;padding-left:4.533%;font-size:10pt;margin-top:8pt;font-family:Times New Roman;margin-bottom:0;text-align:justify;"><span style="font-size:10pt;font-family:Times New Roman;"><ix:nonNumeric id="F_91819eed-53d4-483e-bb1c-1f2cee15086f" contextRef="C_0b02fbbc-b6dd-4e8a-8fd8-6ba51a222673" name="dei:WrittenCommunications" format="ixt:fixed-false"><span style="color:#000000;white-space:pre-wrap;font-size:10pt;font-family:Times New Roman;min-width:fit-content;">&#9744;</span></ix:nonNumeric></span><span style="color:#000000;white-space:pre-wrap;font-size:10pt;font-family:Times New Roman;min-width:fit-content;">	Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)</span><span style="color:#000000;white-space:pre-wrap;font-size:10pt;font-family:Times New Roman;min-width:fit-content;"> </span></p>
  <p style="text-indent:-4.749%;padding-left:4.533%;font-size:10pt;margin-top:8pt;font-family:Times New Roman;margin-bottom:0;text-align:justify;"><span style="font-size:10pt;font-family:Times New Roman;"><ix:nonNumeric id="F_aeee2dab-e6aa-4b26-8b6b-5259de282337" contextRef="C_0b02fbbc-b6dd-4e8a-8fd8-6ba51a222673" name="dei:SolicitingMaterial" format="ixt:fixed-false"><span style="color:#000000;white-space:pre-wrap;font-size:10pt;font-family:Times New Roman;min-width:fit-content;">&#9744;</span></ix:nonNumeric></span><span style="color:#000000;white-space:pre-wrap;font-size:10pt;font-family:Times New Roman;min-width:fit-content;">	Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)</span><span style="color:#000000;white-space:pre-wrap;font-size:10pt;font-family:Times New Roman;min-width:fit-content;"> </span></p>
  <p style="text-indent:-4.749%;padding-left:4.533%;font-size:10pt;margin-top:8pt;font-family:Times New Roman;margin-bottom:0;text-align:justify;"><span style="font-size:10pt;font-family:Times New Roman;"><ix:nonNumeric id="F_33a16a67-6c22-4633-a0ea-1a23ac77e176" contextRef="C_0b02fbbc-b6dd-4e8a-8fd8-6ba51a222673" name="dei:PreCommencementTenderOffer" format="ixt:fixed-false"><span style="color:#000000;white-space:pre-wrap;font-size:10pt;font-family:Times New Roman;min-width:fit-content;">&#9744;</span></ix:nonNumeric></span><span style="color:#000000;white-space:pre-wrap;font-size:10pt;font-family:Times New Roman;min-width:fit-content;">	Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))</span><span style="color:#000000;white-space:pre-wrap;font-size:10pt;font-family:Times New Roman;min-width:fit-content;"> </span></p>
  <p style="text-indent:-4.749%;padding-left:4.533%;font-size:10pt;margin-top:8pt;font-family:Times New Roman;margin-bottom:0;text-align:justify;"><span style="font-size:10pt;font-family:Times New Roman;"><ix:nonNumeric id="F_7669c720-373c-4df2-bef8-814b99a1cf2b" contextRef="C_0b02fbbc-b6dd-4e8a-8fd8-6ba51a222673" name="dei:PreCommencementIssuerTenderOffer" format="ixt:fixed-false"><span style="color:#000000;white-space:pre-wrap;font-size:10pt;font-family:Times New Roman;min-width:fit-content;">&#9744;</span></ix:nonNumeric></span><span style="color:#000000;white-space:pre-wrap;font-size:10pt;font-family:Times New Roman;min-width:fit-content;">	Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))</span><span style="color:#000000;white-space:pre-wrap;font-size:10pt;font-family:Times New Roman;min-width:fit-content;"> </span></p>
  <p style="font-size:10pt;margin-top:6pt;font-family:Times New Roman;margin-bottom:0;text-align:justify;"><span style="color:#000000;white-space:pre-wrap;font-size:10pt;font-family:Times New Roman;min-width:fit-content;">Securities registered pursuant to Section 12(b) of the Act:</span></p>
  <p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:0;text-align:justify;"><span style="white-space:pre-wrap;font-size:9pt;font-family:Times New Roman;min-width:fit-content;">&#160;</span></p>
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    <td style="width:38.78%;"/>
    <td style="width:1%;"/>
    <td style="width:20.22%;"/>
    <td style="width:1.12%;"/>
    <td style="width:38.88%;"/>
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    <td style="vertical-align:top;text-align:right;"><p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:0;text-align:justify;"><span style="color:#000000;white-space:pre-wrap;text-decoration:underline;min-width:fit-content;">Title of each class</span></p></td>
    <td style="vertical-align:top;text-align:right;"><p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:0;text-align:justify;"><span style="white-space:pre-wrap;min-width:fit-content;">&#160;</span></p></td>
    <td style="vertical-align:top;text-align:left;"><p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:0;text-align:center;"><span style="color:#000000;white-space:pre-wrap;text-decoration:underline;min-width:fit-content;">Trading Symbol</span></p></td>
    <td style="vertical-align:top;text-align:right;"><p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:0;text-align:justify;"><span style="white-space:pre-wrap;min-width:fit-content;">&#160;</span></p></td>
    <td style="vertical-align:top;text-align:left;"><p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:0;text-align:center;"><span style="color:#000000;white-space:pre-wrap;text-decoration:underline;min-width:fit-content;">Name of exchange on which registered</span></p></td>
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    <td style="vertical-align:top;text-align:right;"><p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:0;text-align:justify;"><span><ix:nonNumeric id="F_441ba35c-52e9-442d-a32b-a182111dce7c" contextRef="C_0b02fbbc-b6dd-4e8a-8fd8-6ba51a222673" name="dei:Security12bTitle"><span style="color:#000000;white-space:pre-wrap;min-width:fit-content;">Common Stock, Par Value $0.01</span></ix:nonNumeric></span></p></td>
    <td style="vertical-align:top;text-align:right;"><p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:0;text-align:justify;"><span style="white-space:pre-wrap;min-width:fit-content;">&#160;</span></p></td>
    <td style="vertical-align:top;text-align:left;"><p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:0;text-align:center;"><span><ix:nonNumeric id="F_3d39e703-b5a8-4422-bc52-628baf91d7f5" contextRef="C_0b02fbbc-b6dd-4e8a-8fd8-6ba51a222673" name="dei:TradingSymbol"><span style="color:#000000;white-space:pre-wrap;min-width:fit-content;">ADTN</span></ix:nonNumeric></span></p></td>
    <td style="vertical-align:top;text-align:right;"><p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:0;text-align:justify;"><span style="white-space:pre-wrap;min-width:fit-content;">&#160;</span></p></td>
    <td style="vertical-align:top;text-align:left;"><p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:0;text-align:center;"><span><ix:nonNumeric id="F_252b49f6-097f-42a7-8b9f-4e4849e4579e" contextRef="C_0b02fbbc-b6dd-4e8a-8fd8-6ba51a222673" name="dei:SecurityExchangeName" format="ixt-sec:exchnameen"><span style="color:#000000;white-space:pre-wrap;min-width:fit-content;">The NASDAQ Global Select Market</span></ix:nonNumeric></span></p></td>
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  <p style="font-size:10pt;margin-top:6pt;font-family:Times New Roman;margin-bottom:0;text-align:justify;"><span style="color:#000000;white-space:pre-wrap;font-size:10pt;font-family:Times New Roman;min-width:fit-content;">Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (&#167;&#8201;230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (&#167;&#8201;240.12b-2 of this chapter).</span></p>
  <p style="font-size:10pt;margin-top:6pt;font-family:Times New Roman;margin-bottom:0;text-align:justify;"><span style="color:#000000;white-space:pre-wrap;font-size:10pt;font-family:Times New Roman;min-width:fit-content;">Emerging growth company </span><span style="font-size:10pt;font-family:Times New Roman;"><ix:nonNumeric id="F_69ff959a-412e-4abe-b06c-32979bd7ea75" contextRef="C_0b02fbbc-b6dd-4e8a-8fd8-6ba51a222673" name="dei:EntityEmergingGrowthCompany" format="ixt:fixed-false"><span style="color:#000000;white-space:pre-wrap;font-size:10pt;font-family:Times New Roman;min-width:fit-content;">&#9744;</span></ix:nonNumeric></span></p>
  <p style="font-size:10pt;margin-top:9pt;font-family:Times New Roman;margin-bottom:0;text-align:justify;"><span style="color:#000000;white-space:pre-wrap;font-size:10pt;font-family:Times New Roman;min-width:fit-content;">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. </span><span style="color:#000000;white-space:pre-wrap;font-size:10pt;font-family:'Wingdings',serif;min-width:fit-content;">&#61608;</span></p>
  <p style="border-top:0.5pt solid #000000;font-size:10pt;margin-top:4.5pt;font-family:Times New Roman;margin-bottom:0;text-align:center;"><span style="color:#000000;white-space:pre-wrap;font-size:4pt;font-family:Times New Roman;min-width:fit-content;"> </span></p>
  <p style="border-top:1pt solid;padding-top:1pt;font-size:10pt;margin-top:1pt;font-family:Times New Roman;margin-bottom:0;text-align:center;"><span style="color:#000000;white-space:pre-wrap;font-size:4pt;font-family:Times New Roman;min-width:fit-content;"> </span></p>
  <div style="flex-direction:column;display:flex;padding-bottom:0.5in;min-height:0.5in;justify-content:flex-end;box-sizing:border-box;"><p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:0;text-align:center;"><span style="white-space:pre-wrap;font-size:9pt;font-family:'Calibri',sans-serif;min-width:fit-content;">&#160;</span></p><p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:0;text-align:left;"><span style="white-space:pre-wrap;font-size:11pt;font-family:'Calibri',sans-serif;min-width:fit-content;">&#160;</span></p></div>
  <hr style="page-break-after:always;"/>
  <div style="padding-top:0.5in;min-height:0.5in;box-sizing:border-box;"><p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:0;text-align:left;"><span style="white-space:pre-wrap;font-size:11pt;font-family:'Calibri',sans-serif;min-width:fit-content;">&#160;</span></p></div>
  <p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:0;text-align:justify;"><span style="color:#000000;white-space:pre-wrap;font-weight:bold;font-size:10pt;font-family:Times New Roman;min-width:fit-content;">Item 2.02	Results of Operations and Financial Condition.</span></p>
  <p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:0;text-align:justify;"><span style="color:#000000;white-space:pre-wrap;font-size:10pt;font-family:Times New Roman;min-width:fit-content;">	</span></p>
  <p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:0;text-align:justify;"><span style="color:#000000;white-space:pre-wrap;font-size:10pt;font-family:Times New Roman;min-width:fit-content;">On May 6, 2024, ADTRAN Holdings, Inc. (&#8220;ADTRAN&#8221;) announced its financial results for the first quarter ended March 31, 2024.</span></p>
  <p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:0;text-align:justify;"><span style="white-space:pre-wrap;font-size:10pt;font-family:Times New Roman;min-width:fit-content;">&#160;</span></p>
  <p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:0;text-align:justify;"><span style="color:#000000;white-space:pre-wrap;font-size:10pt;font-family:Times New Roman;min-width:fit-content;">A copy of ADTRAN&#8217;s press release announcing its financial results is attached as Exhibit 99.1 hereto and incorporated by reference herein.</span></p>
  <p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:0;text-align:justify;"><span style="white-space:pre-wrap;font-size:10pt;font-family:Times New Roman;min-width:fit-content;">&#160;</span></p>
  <p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:0;text-align:justify;"><span style="color:#000000;white-space:pre-wrap;font-weight:bold;font-size:10pt;font-family:Times New Roman;min-width:fit-content;">Item 7.01	Regulation FD Disclosure.</span></p>
  <p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:0;text-align:left;"><span style="white-space:pre-wrap;font-size:10pt;font-family:Times New Roman;min-width:fit-content;">&#160;</span></p>
  <p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:0;text-align:left;"><span style="color:#000000;white-space:pre-wrap;font-size:10pt;font-family:Times New Roman;min-width:fit-content;">Executives from ADTRAN will review the financial results via a live audio webcast on Tuesday, May 7, 2024, at 9:30 a.m. Central Time, or 4:30 p.m. Central European Summer Time. A copy of the investor presentation provided in connection with that review is attached as Exhibit 99.2 and incorporated by reference herein. An archived recording of the webcast will be available for a limited time on the Investor Relations page of investors.adtran.com.</span></p>
  <p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:0;text-align:left;"><span style="white-space:pre-wrap;font-size:10pt;font-family:Times New Roman;min-width:fit-content;">&#160;</span></p>
  <p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:0;text-align:justify;"><span style="color:#000000;white-space:pre-wrap;font-size:10pt;font-family:Times New Roman;min-width:fit-content;">The information included in, or furnished with, Item 2.02 and 7.01 of this Current Report on Form 8-K shall not be deemed &#8220;filed&#8221; for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the &#8220;Exchange Act&#8221;), nor shall it be deemed incorporated by reference in any filing under the Securities Act of 1933, as amended, or the Exchange Act, except as shall be expressly set forth by specific reference in such a filing.</span></p>
  <p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:0;text-align:justify;"><span style="white-space:pre-wrap;font-size:10pt;font-family:Times New Roman;min-width:fit-content;">&#160;</span></p>
  <p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:0;text-align:left;"><span style="white-space:pre-wrap;font-size:10pt;font-family:Times New Roman;min-width:fit-content;">&#160;</span></p>
  <p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:0;text-align:justify;"><span style="color:#000000;white-space:pre-wrap;font-weight:bold;font-size:10pt;font-family:Times New Roman;min-width:fit-content;">Item 9.01	Financial Statements and Exhibits.</span></p>
  <p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:0;text-align:justify;"><span style="color:#000000;white-space:pre-wrap;font-size:10pt;font-family:Times New Roman;min-width:fit-content;">	</span></p>
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    <td style="width:79.82%;"/>
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    <td style="padding-left:0.075in;vertical-align:bottom;padding-right:0.075in;text-align:right;"><p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:6pt;text-align:justify;"><span style="color:#000000;white-space:pre-wrap;font-weight:bold;text-decoration:underline;min-width:fit-content;">Exhibit Number</span></p></td>
    <td style="padding-left:0.075in;vertical-align:bottom;padding-right:0.075in;"><p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:6pt;text-align:left;"><span style="color:#000000;white-space:pre-wrap;font-weight:bold;text-decoration:underline;min-width:fit-content;">Description</span></p></td>
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    <td style="padding-left:0.075in;vertical-align:top;padding-right:0.075in;text-align:left;"><p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:6pt;text-align:center;"><span style="color:#000000;white-space:pre-wrap;min-width:fit-content;">99.1</span></p></td>
    <td style="padding-left:0.075in;vertical-align:bottom;padding-right:0.075in;"><p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:6pt;text-align:left;"><a href="adtn-ex99_1.htm"><span style="color:#0000ff;white-space:pre-wrap;text-decoration:underline;min-width:fit-content;">Press Release dated May 6, 2024</span></a></p></td>
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    <td style="padding-left:0.075in;vertical-align:top;padding-right:0.075in;text-align:left;"><p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:6pt;text-align:center;"><span style="color:#000000;white-space:pre-wrap;min-width:fit-content;">99.2</span></p></td>
    <td style="padding-left:0.075in;vertical-align:bottom;padding-right:0.075in;"><p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:6pt;text-align:left;"><a href="adtn-ex99_2.htm"><span style="color:#0000ff;white-space:pre-wrap;text-decoration:underline;min-width:fit-content;">Visual Presentation of May 7, 2024</span></a></p></td>
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    <td style="padding-left:0.075in;vertical-align:top;padding-right:0.075in;text-align:left;"><p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:6pt;text-align:center;"><span style="color:#000000;white-space:pre-wrap;min-width:fit-content;">104</span></p></td>
    <td style="padding-left:0.075in;vertical-align:bottom;padding-right:0.075in;"><p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:6pt;text-align:left;"><span style="color:#000000;white-space:pre-wrap;min-width:fit-content;">Cover Page Interactive Data File &#8211; the cover page iXBRL tags are embedded within the Inline XBRL document</span></p></td>
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    <td style="padding-left:0.075in;vertical-align:top;padding-right:0.075in;text-align:left;"><p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:6pt;text-align:center;"><span style="white-space:pre-wrap;min-width:fit-content;">&#160;</span></p></td>
    <td style="padding-left:0.075in;vertical-align:bottom;padding-right:0.075in;"><p style="font-size:11pt;margin-top:0;font-family:Times New Roman;margin-bottom:6pt;text-align:left;"><span style="white-space:pre-wrap;min-width:fit-content;">&#160;</span></p></td>
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  <p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:0;text-align:left;"><span style="white-space:pre-wrap;font-size:10pt;font-family:Times New Roman;min-width:fit-content;">&#160;</span></p>
  <p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:0;text-align:left;"><span style="white-space:pre-wrap;font-size:10pt;font-family:Times New Roman;min-width:fit-content;">&#160;</span></p>
  <p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:0;text-align:left;"><span style="white-space:pre-wrap;font-size:10pt;font-family:Times New Roman;min-width:fit-content;">&#160;</span></p>
  <p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:0;text-align:left;"><span style="white-space:pre-wrap;font-size:10pt;font-family:Times New Roman;min-width:fit-content;">&#160;</span></p>
  <p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:0;text-align:left;"><span style="white-space:pre-wrap;font-size:10pt;font-family:Times New Roman;min-width:fit-content;">&#160;</span></p>
  <div style="flex-direction:column;display:flex;padding-bottom:0.5in;min-height:0.5in;justify-content:flex-end;box-sizing:border-box;"><p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:0;text-align:center;"><span style="white-space:pre-wrap;font-size:9pt;font-family:'Calibri',sans-serif;min-width:fit-content;">&#160;</span></p><p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:0;text-align:left;"><span style="white-space:pre-wrap;font-size:11pt;font-family:'Calibri',sans-serif;min-width:fit-content;">&#160;</span></p></div>
  <hr style="page-break-after:always;"/>
  <div style="padding-top:0.5in;min-height:0.5in;box-sizing:border-box;"><p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:0;text-align:left;"><span style="white-space:pre-wrap;font-size:11pt;font-family:'Calibri',sans-serif;min-width:fit-content;">&#160;</span></p></div>
  <p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:0;text-align:center;"><span style="color:#000000;white-space:pre-wrap;font-weight:bold;font-size:10pt;font-family:Times New Roman;min-width:fit-content;">SIGNATURES</span></p>
  <p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:0;text-align:center;"><span style="white-space:pre-wrap;font-size:10pt;font-family:Times New Roman;min-width:fit-content;">&#160;</span></p>
  <p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:12pt;text-align:left;"><span style="color:#000000;white-space:pre-wrap;font-size:10pt;font-family:Times New Roman;min-width:fit-content;">	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.</span></p>
  <p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:12pt;text-align:left;"><span style="white-space:pre-wrap;font-size:10pt;font-family:Times New Roman;min-width:fit-content;">&#160;</span></p>
  <table style="border-spacing:0;table-layout:fixed;width:100.0%;border-collapse:separate;">
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    <td style="padding-left:0.075in;vertical-align:top;padding-right:0.075in;text-align:right;"><p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:12pt;text-align:justify;"><span style="color:#000000;white-space:pre-wrap;min-width:fit-content;">Date: May 7, 2024</span><span style="color:#000000;white-space:pre-wrap;min-width:fit-content;">                                            </span></p></td>
    <td style="padding-left:0.075in;vertical-align:top;padding-right:0.075in;"><p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:0;text-align:left;"><span style="color:#000000;white-space:pre-wrap;font-weight:bold;min-width:fit-content;">ADTRAN Holdings, Inc.</span></p><p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:0;text-align:left;"><span style="white-space:pre-wrap;min-width:fit-content;">&#160;</span></p><p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:0;text-align:left;"><span style="color:#000000;white-space:pre-wrap;min-width:fit-content;">By</span><span style="color:#000000;white-space:pre-wrap;text-decoration:underline;min-width:fit-content;">: /s/ Ulrich Dopfer		</span><span style="color:#000000;white-space:pre-wrap;min-width:fit-content;"><br/>Ulrich Dopfer</span><span style="color:#000000;white-space:pre-wrap;min-width:fit-content;"> </span></p><p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:0;text-align:left;"><span style="color:#000000;white-space:pre-wrap;min-width:fit-content;">Chief Financial Officer</span><span style="color:#000000;white-space:pre-wrap;min-width:fit-content;"> </span></p><p style="font-size:10pt;margin-top:0;font-family:Times New Roman;margin-bottom:0;text-align:left;"><span style="color:#000000;white-space:pre-wrap;min-width:fit-content;">(Duly Authorized Officer and Principal Financial Officer)</span></p></td>
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8-K
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):
May 6, 2024
ADTRAN Holdings, Inc.
(Exact name of Registrant as Specified in Its Charter)
Delaware
001-41446
87-2164282
(State or Other Jurisdiction
of Incorporation)
(Commission File Number)
(IRS Employer
Identification No.)
901 Explorer Boulevard
Huntsville
,
Alabama
35806-2807
(Address of Principal Executive Offices)
(Zip Code)
Registrant's Telephone Number, Including Area Code:
(256)
963-8000
Not Applicable
(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 Instructions 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))
Securities registered pursuant to Section 12(b) of the Act:
Title of each class
Trading Symbol
Name of exchange on which registered
Common Stock, Par Value $0.01
ADTN
The NASDAQ Global Select Market
Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§ 230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§ 240.12b-2 of this chapter).
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.

Item 2.02	Results of Operations and Financial Condition.
On May 6, 2024, ADTRAN Holdings, Inc. ("ADTRAN") announced its financial results for the first quarter ended March 31, 2024.
A copy of ADTRAN's press release announcing its financial results is attached as Exhibit 99.1 hereto and incorporated by reference herein.
Item 7.01	Regulation FD Disclosure.
Executives from ADTRAN will review the financial results via a live audio webcast on Tuesday, May 7, 2024, at 9:30 a.m. Central Time, or 4:30 p.m. Central European Summer Time. A copy of the investor presentation provided in connection with that review is attached as Exhibit 99.2 and incorporated by reference herein. An archived recording of the webcast will be available for a limited time on the Investor Relations page of investors.adtran.com.
The information included in, or furnished with, Item 2.02 and 7.01 of this Current Report on Form 8-K shall not be deemed "filed" for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the "Exchange Act"), nor shall it be deemed incorporated by reference in any filing under the Securities Act of 1933, as amended, or the Exchange Act, except as shall be expressly set forth by specific reference in such a filing.
Item 9.01	Financial Statements and Exhibits.
Exhibit Number
Description
99.1
Press Release dated May 6, 2024
99.2
Visual Presentation of May 7, 2024
104
Cover Page Interactive Data File – the cover page iXBRL tags are embedded within the Inline XBRL document
SIGNATURES
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.
Date: May 7, 2024
ADTRAN Holdings, Inc.
By
: /s/ Ulrich Dopfer
Ulrich Dopfer
Chief Financial Officer
(Duly Authorized Officer and Principal Financial Officer)