<SEC-DOCUMENT>0001193125-23-209042.txt : 20230810
<SEC-HEADER>0001193125-23-209042.hdr.sgml : 20230810
<ACCEPTANCE-DATETIME>20230810160928
ACCESSION NUMBER:		0001193125-23-209042
CONFORMED SUBMISSION TYPE:	NT 10-Q
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20230630
FILED AS OF DATE:		20230810
DATE AS OF CHANGE:		20230810
EFFECTIVENESS DATE:		20230810

FILER:

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			ADTRAN Holdings, Inc.
		CENTRAL INDEX KEY:			0000926282
		STANDARD INDUSTRIAL CLASSIFICATION:	TELEPHONE & TELEGRAPH APPARATUS [3661]
		IRS NUMBER:				872164282
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		NT 10-Q
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-41446
		FILM NUMBER:		231159396

	BUSINESS ADDRESS:	
		STREET 1:		901 EXPLORER BLVD
		CITY:			HUNTSVILLE
		STATE:			AL
		ZIP:			35806
		BUSINESS PHONE:		256-963-8220

	MAIL ADDRESS:	
		STREET 1:		901 EXPLORER BLVD
		CITY:			HUNTSVILLE
		STATE:			AL
		ZIP:			35806

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	ADTRAN INC
		DATE OF NAME CHANGE:	19940705
</SEC-HEADER>
<DOCUMENT>
<TYPE>NT 10-Q
<SEQUENCE>1
<FILENAME>d445855dnt10q.htm
<DESCRIPTION>NT 10-Q
<TEXT>
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<TITLE>NT 10-Q</TITLE>
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<Center><DIV STYLE="width:8.5in" align="left">
 <P STYLE="line-height:1.0pt;margin-top:0pt;margin-bottom:0pt;border-bottom:1px solid #000000">&nbsp;</P>
<P STYLE="line-height:3.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1px solid #000000">&nbsp;</P> <P STYLE="margin-top:4pt; margin-bottom:0pt; font-size:18pt; font-family:Times New Roman" ALIGN="center"><B>UNITED STATES </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:18pt; font-family:Times New Roman" ALIGN="center"><B>SECURITIES AND EXCHANGE COMMISSION </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:12pt; font-family:Times New Roman" ALIGN="center"><B>Washington, D.C. 20549 </B></P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><center>
<P STYLE="line-height:6.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1.00pt solid #000000;width:21%">&nbsp;</P></center> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:18pt; font-family:Times New Roman" ALIGN="center"><B>FORM <FONT
STYLE="white-space:nowrap">12b-25</FONT> </B></P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><center>
<P STYLE="line-height:6.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1.00pt solid #000000;width:21%">&nbsp;</P></center> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:12pt; font-family:Times New Roman" ALIGN="center"><B>NOTIFICATION
OF LATE FILING </B></P> <P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="right">SEC File Number <B><FONT STYLE="white-space:nowrap">000-41446</FONT></B> </P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="right">CUSIP Number <B>00486H105</B> </P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD VALIGN="top" ALIGN="right"><I>(Check One)&nbsp;&nbsp;&nbsp;&nbsp;</I></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">&#9744;&nbsp;&nbsp;Form <FONT STYLE="white-space:nowrap">10-K</FONT> &nbsp;&nbsp;&nbsp;&nbsp;&#9744;&nbsp;&nbsp;Form <FONT
STYLE="white-space:nowrap">20-F</FONT> &nbsp;&nbsp;&nbsp;&nbsp;&#9744;&nbsp;&nbsp;Form <FONT STYLE="white-space:nowrap">11-K</FONT> &nbsp;&nbsp;&nbsp;&nbsp;&#9746;&nbsp;&nbsp;Form <FONT STYLE="white-space:nowrap">10-Q</FONT></P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">&#9744;&nbsp;&nbsp;Form <FONT STYLE="white-space:nowrap">10-D</FONT> &nbsp;&nbsp;&nbsp;&nbsp;&#9744;&nbsp;&nbsp;Form
<FONT STYLE="white-space:nowrap">N-CEN</FONT> &nbsp;&nbsp;&nbsp;&nbsp;&#9744;&nbsp;&nbsp;Form <FONT STYLE="white-space:nowrap">N-CSR</FONT></P></TD></TR>
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<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">For Period Ended: June&nbsp;30, 2023</TD></TR>
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<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&#9744;&nbsp;&nbsp;Transition Report on Form&nbsp;10-K</TD></TR>
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<TD HEIGHT="2"></TD>
<TD HEIGHT="2" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&#9744;&nbsp;&nbsp;Transition Report on Form&nbsp;20-F</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="2"></TD>
<TD HEIGHT="2" COLSPAN="2"></TD></TR>
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<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&#9744;&nbsp;&nbsp;Transition Report on Form&nbsp;11-K</TD></TR>
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<TD HEIGHT="2"></TD>
<TD HEIGHT="2" COLSPAN="2"></TD></TR>
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<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&#9744;&nbsp;&nbsp;Transition Report on Form&nbsp;10-Q</TD></TR>
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<TD HEIGHT="2"></TD>
<TD HEIGHT="2" COLSPAN="2"></TD></TR>
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<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&#9744;&nbsp;&nbsp;Transition Report on Form <FONT STYLE="white-space:nowrap">N-SAR</FONT></TD></TR>
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<TD VALIGN="bottom">For the Transition Period Ended: _______________</TD></TR>
</TABLE> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><div style="max-width:100%;margin-left:0%; margin-right:0%;border:solid 1px;background-color:;;padding-top:2pt;padding-bottom:3pt">
<P STYLE="margin-top:0pt; margin-bottom:0pt; padding-top:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Nothing in this form shall be construed to imply that the Commission has verified any information contained herein.
</B></P></div> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">If the notification relates to a portion of the filing checked above, identify the Item(s) to which the notification relates: </P>
<P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</P>
<P STYLE="line-height:1.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1px solid #000000">&nbsp;</P> <P STYLE="margin-top:18pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>PART I &#150; REGISTRANT
INFORMATION </B></P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:22pt; font-family:Times New Roman" ALIGN="center"><B>ADTRAN Holdings, Inc. </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Full Name of Registrant </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>N/A </B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Former Name if
Applicable </B></P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>901 Explorer Boulevard </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Address of Principal Executive Office (Street and Number) </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Huntsville, Alabama 35806-2807 </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>City, State and Zip Code </B></P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<P STYLE="line-height:1.5pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1.50pt solid #000000">&nbsp;</P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>PART II&#150;RULES <FONT
STYLE="white-space:nowrap">12b-25(b)</FONT> AND (c) </B></P> <P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">If the subject report could not be filed without unreasonable effort or expense
and the registrant seeks relief pursuant to Rule <FONT STYLE="white-space:nowrap">12b-25(b),</FONT> the following should be completed. (<I>Check box if appropriate</I>) </P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD VALIGN="middle" ROWSPAN="3">&#9746;&nbsp;&nbsp;&nbsp;</TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000">&nbsp;</TD>
<TD VALIGN="top">(a)</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">The reasons described in reasonable detail in Part III of this form could not be eliminated without unreasonable effort or expense;</P>
<P STYLE="font-size:6pt; margin-top:0pt; margin-bottom:1pt">&nbsp;</P></TD></TR>
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<TD VALIGN="top">(b)</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">The subject annual report, semi-annual report, transition report on Form <FONT STYLE="white-space:nowrap">10-K,</FONT> Form <FONT
STYLE="white-space:nowrap">20-F,</FONT> Form <FONT STYLE="white-space:nowrap">11-K,</FONT> Form <FONT STYLE="white-space:nowrap">N-CEN</FONT> or Form <FONT STYLE="white-space:nowrap">N-CSR,</FONT> or portion thereof, will be filed on or before the
fifteenth calendar day following the prescribed due date; or the subject quarterly report or transition report on Form <FONT STYLE="white-space:nowrap">10-Q</FONT> or subject distribution report on Form <FONT STYLE="white-space:nowrap">10-D,</FONT>
or portion thereof, will be filed on or before the fifth calendar day following the prescribed due date; and</P> <P STYLE="font-size:6pt; margin-top:0pt; margin-bottom:1pt">&nbsp;</P></TD></TR>
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<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000">&nbsp;</TD>
<TD VALIGN="top">(c)</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top">The accountant&#146;s statement or other exhibit required by Rule <FONT STYLE="white-space:nowrap">12b-25(c)</FONT> has been attached if applicable.</TD></TR>
</TABLE> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="line-height:1.5pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1.50pt solid #000000">&nbsp;</P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>PART III&#150; NARRATIVE </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">State below in reasonable detail the reasons why Forms <FONT STYLE="white-space:nowrap">10-K,</FONT>
<FONT STYLE="white-space:nowrap">20-F,</FONT> <FONT STYLE="white-space:nowrap">11-K,</FONT> <FONT STYLE="white-space:nowrap">10-Q,</FONT> <FONT STYLE="white-space:nowrap">10-D,</FONT> <FONT STYLE="white-space:nowrap">N-CEN,</FONT> <FONT
STYLE="white-space:nowrap">N-CSR,</FONT> or the transition report or portion thereof, could not be filed within the prescribed time period. </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">ADTRAN Holdings, Inc. (the &#147;Company&#148;) is unable, without unreasonable effort or expense, to file its Quarterly Report on Form <FONT
STYLE="white-space:nowrap">10-Q</FONT> for the quarter ended June&nbsp;30, 2023 (the &#147;Q2 Form <FONT STYLE="white-space:nowrap">10-Q&#148;)</FONT> with the Securities and Exchange Commission (the &#147;SEC&#148;) within the prescribed time
period for the reasons set forth below. </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">As disclosed in the Company&#146;s Current Report on Form
<FONT STYLE="white-space:nowrap">8-K</FONT> filed with the SEC on August&nbsp;10, 2023 (the &#147;August 10, 2023 Form <FONT STYLE="white-space:nowrap">8-K&#148;),</FONT> subsequent to the Company&#146;s earnings call on August&nbsp;8, 2023 and
during the preparation of the unaudited condensed consolidated financial statements to be included in the Q2 Form <FONT STYLE="white-space:nowrap">10-Q,</FONT> the Company determined that the principal amount of indebtedness outstanding under the
Company&#146;s revolving credit facility with a syndicate of banks, including Wells Fargo Bank, National Association (&#147;Wells Fargo&#148;), of $200&nbsp;million at June&nbsp;30, 2023 were noncurrent liabilities in the Company&#146;s consolidated
balance sheet. Therefore, the outstanding Wells Fargo revolving credit facility balances for the following prior periods were misclassified and will be adjusted from current to noncurrent liabilities on the balance sheets as follows:
$60.0&nbsp;million as of September&nbsp;30, 2022, $60.0&nbsp;million as of December&nbsp;31, 2022, and $180.0&nbsp;million as of March&nbsp;31, 2023. Furthermore, in connection with the restatement of the December&nbsp;31, 2022 financial statements,
the Company will also correct certain errors related to the presentation of deferred tax assets (&#147;DTAs&#148;) and deferred tax liabilities (&#147;DTLs&#148;) on the balance sheets that were previously assessed as immaterial errors and that had
been corrected in the Company&#146;s Form <FONT STYLE="white-space:nowrap">10-Q</FONT> for the quarter ended March&nbsp;31, 2023. Neither the adjustment of credit facility balances nor the correction of the presentation of DTAs and DTLs have any
impact on, or result in any change to, the Company&#146;s reported statements of income (loss) or statements of cash flows. </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">As disclosed
in the August&nbsp;10, 2023 Form <FONT STYLE="white-space:nowrap">8-K</FONT> as a result of the misclassification, the Company determined that a material weakness existed in its Internal Control Over Financial Reporting (&#147;ICFR&#148;) as of
December&nbsp;31, 2022. </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">The Company has determined that it will prepare and file amendments to the Company&#146;s Quarterly Report on
Form <FONT STYLE="white-space:nowrap">10-Q</FONT> for the fiscal quarter ended September&nbsp;30, 2022, Annual Report on Form <FONT STYLE="white-space:nowrap">10-K</FONT> for the fiscal year ended December&nbsp;31, 2022, and Quarterly Report on Form
<FONT STYLE="white-space:nowrap">10-Q</FONT> for the fiscal quarter ended March&nbsp;31, 2023, in order to restate the consolidated financial statements and disclose that a material weakness existed and that our disclosure controls and procedures
were not effective beginning as of September&nbsp;30, 2022 and all subsequent periods through the date of this filing. Given the scope of the process to prepare the restatement and related disclosures, the Company is unable to complete and file the
Q2 Form <FONT STYLE="white-space:nowrap">10-Q</FONT> by the required due date of August&nbsp;9, 2023 without unreasonable effort and expense. The Company does, however, expect to file such report within five calendar days thereof. </P>
<P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="line-height:1.5pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1.50pt solid #000000">&nbsp;</P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>PART IV&#150; OTHER INFORMATION </B></P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD VALIGN="top">(1)</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;&nbsp;&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" COLSPAN="9">Name and telephone number of person to contact in regard to this notification</TD></TR>
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<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
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<TD VALIGN="bottom" STYLE=" BORDER-BOTTOM:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center" STYLE="BORDER-BOTTOM:1px solid #000000"><B>Ulrich Dopfer, Chief Financial Officer</B></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center"><B>&nbsp;&nbsp;&nbsp;&nbsp;</B></TD>
<TD VALIGN="bottom" STYLE=" BORDER-BOTTOM:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center" STYLE="BORDER-BOTTOM:1px solid #000000"><B>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(256) &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</B></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center"><B>&nbsp;&nbsp;&nbsp;&nbsp;</B></TD>
<TD VALIGN="bottom" STYLE=" BORDER-BOTTOM:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center" STYLE="BORDER-BOTTOM:1px solid #000000"><B><FONT STYLE="white-space:nowrap">963-8000</FONT></B></TD></TR>
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<TD VALIGN="bottom" ALIGN="center">(Name)</TD>
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<TD VALIGN="bottom" ALIGN="center">(Area&nbsp;Code)</TD>
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<TD VALIGN="bottom" ALIGN="center">(Telephone&nbsp;Number)</TD></TR>
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<TD VALIGN="top">(2)</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" COLSPAN="9">Have all other periodic reports required under Section&nbsp;13 or 15(d) of the Securities Exchange Act of 1934 or Section&nbsp;30 of the Investment Company Act of 1940 during the preceding 12 months or for such
shorter period that the registrant was required to file such report(s) been filed? If answer is no, identify report(s).&nbsp;&nbsp;&nbsp;&nbsp;&#9746;&nbsp;&nbsp;Yes&nbsp;&nbsp;&nbsp;&nbsp;&#9744;&nbsp;&nbsp;No</TD></TR>
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<TD VALIGN="bottom">&nbsp;</TD>
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<TD VALIGN="bottom" STYLE=" BORDER-BOTTOM:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" COLSPAN="9" STYLE="BORDER-BOTTOM:1px solid #000000"><FONT STYLE="font-size:10pt">&nbsp;&nbsp;&nbsp;&nbsp;</FONT></TD></TR>
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<TD VALIGN="top">(3)</TD>
<TD VALIGN="bottom">&nbsp;</TD>
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<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" COLSPAN="9">Is it anticipated that any significant change in results of operations from the corresponding period for the last fiscal year will be reflected by the earnings statements to be included in the subject report or
portion thereof?&nbsp;&nbsp;&nbsp;&nbsp;&#9746;&nbsp;&nbsp;Yes&nbsp;&nbsp;&nbsp;&nbsp;&#9744;&nbsp;&nbsp;No</TD></TR>
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<TD HEIGHT="8" COLSPAN="10"></TD></TR>
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<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" COLSPAN="9"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">If so, attach an explanation of the anticipated change, both narratively and quantitatively, and, if appropriate, state the
reasons why a reasonable estimate of the results cannot be made.</P> <P STYLE="font-size:6pt; margin-top:0pt; margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">The Company&#146;s
condensed consolidated statements of loss for the quarter and six months ended June&nbsp;30, 2023 compared to the condensed consolidated statements of income for the corresponding periods in the prior fiscal year are set forth in the Company&#146;s
press release dated August&nbsp;6, 2023, which is attached to the Company&#146;s Form <FONT STYLE="white-space:nowrap">8-K</FONT> furnished to the SEC on August&nbsp;7, 2023.</P></TD></TR>
</TABLE> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><B><I>Forward-Looking Statements </I></B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">This Notification of Late Filing contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of
1995. Forward-looking statements include, among other things, statements regarding the Company&#146;s intent to restate its prior consolidated financial statements for the <FONT STYLE="white-space:nowrap">Non-Reliance</FONT> Periods, the estimated
impact of adjustments to the financial statements for the <FONT STYLE="white-space:nowrap">Non-Reliance</FONT> Periods, the impact of the Company&#146;s material weakness in financial control over financial reporting and the Company&#146;s
disclosure controls and procedures on its financial statements and other public disclosures, the anticipated timing for filing the Company&#146;s Form <FONT STYLE="white-space:nowrap">10-Q</FONT> for the second quarter of 2023 and related matters.
Forward-looking statements include statements that are not historical facts and can be identified by terms such as &#147;anticipate,&#148; &#147;believe,&#148; &#147;could,&#148; &#147;estimate,&#148; &#147;expect,&#148; &#147;intend,&#148;
&#147;may,&#148; &#147;plan,&#148; &#147;potential,&#148; &#147;predict,&#148; &#147;project,&#148; &#147;seek,&#148; &#147;should,&#148; &#147;will,&#148; &#147;would&#148; or similar expressions and the negatives of those terms. Our actual results
and the timing of events could materially differ from those anticipated in such forward-looking statements as a result of certain risks and uncertainties including those described in more detail in the Company&#146;s most recent Annual Report on
Form <FONT STYLE="white-space:nowrap">10-K</FONT> and Quarterly Report on Form <FONT STYLE="white-space:nowrap">10-Q</FONT> and other documents on file with the SEC, as well as the risk of the possibility of further material delays in the
Company&#146;s financial reporting. The Company disclaims and does not undertake any obligation to update or revise any forward-looking statement in this filing, except as required by applicable law or regulation. </P>
<P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="line-height:1.5pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1.50pt solid #000000">&nbsp;</P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>ADTRAN Holdings, Inc. </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">(Name of Registrant as Specified in Charter) </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">has
caused this notification to be signed on its behalf by the undersigned thereunto duly authorized. </P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD VALIGN="top">Date: August&nbsp;10, 2023</TD>
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<TD VALIGN="top">By:</TD>
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<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:1pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman">/s/ Ulrich Dopfer</P></TD></TR>
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<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Ulrich Dopfer</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">Chief Financial
Officer</P></TD></TR>
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