<SEC-DOCUMENT>0000102909-26-000569.txt : 20260326
<SEC-HEADER>0000102909-26-000569.hdr.sgml : 20260326
<ACCEPTANCE-DATETIME>20260326152518
ACCESSION NUMBER:		0000102909-26-000569
CONFORMED SUBMISSION TYPE:	SCHEDULE 13G/A
PUBLIC DOCUMENT COUNT:		1
FILED AS OF DATE:		20260326
DATE AS OF CHANGE:		20260326

SUBJECT COMPANY:	

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			ALLEGRO MICROSYSTEMS, INC.
		CENTRAL INDEX KEY:			0000866291
		STANDARD INDUSTRIAL CLASSIFICATION:	SEMICONDUCTORS & RELATED DEVICES [3674]
		ORGANIZATION NAME:           	04 Manufacturing
		EIN:				462405937
		FISCAL YEAR END:			0331

	FILING VALUES:
		FORM TYPE:		SCHEDULE 13G/A
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	005-92108
		FILM NUMBER:		26797558

	BUSINESS ADDRESS:	
		STREET 1:		955 PERIMETER ROAD
		CITY:			MANCHESTER
		STATE:			NH
		ZIP:			03103
		BUSINESS PHONE:		(603) 626-2300

	MAIL ADDRESS:	
		STREET 1:		955 PERIMETER ROAD
		CITY:			MANCHESTER
		STATE:			NH
		ZIP:			03103

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	ALLEGRO MICROSYSTEMS INC
		DATE OF NAME CHANGE:	19900730

FILED BY:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			VANGUARD GROUP INC
		CENTRAL INDEX KEY:			0000102909
		ORGANIZATION NAME:           	
		EIN:				231945930
		STATE OF INCORPORATION:			PA
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		SCHEDULE 13G/A

	BUSINESS ADDRESS:	
		STREET 1:		100 VANGUARD BLVD
		CITY:			MALVERN
		STATE:			PA
		ZIP:			19355
		BUSINESS PHONE:		6106691000

	MAIL ADDRESS:	
		STREET 1:		PO BOX 2600
		STREET 2:		V26
		CITY:			VALLEY FORGE
		STATE:			PA
		ZIP:			19482-2600
</SEC-HEADER>
<DOCUMENT>
<TYPE>SCHEDULE 13G/A
<SEQUENCE>1
<FILENAME>primary_doc.xml
<TEXT>
<XML>
<?xml version="1.0" encoding="UTF-8"?><edgarSubmission xmlns="http://www.sec.gov/edgar/schedule13g" xmlns:com="http://www.sec.gov/edgar/common">
<schemaVersion>X0202</schemaVersion>
<headerData>
<submissionType>SCHEDULE 13G/A</submissionType>
<filerInfo>
<filer>
<filerCredentials>
<cik>0000102909</cik>
<ccc>XXXXXXXX</ccc>
</filerCredentials>
</filer>
<liveTestFlag>LIVE</liveTestFlag>
</filerInfo>
</headerData>
<formData>
<coverPageHeader>
<amendmentNo>2</amendmentNo>
<securitiesClassTitle>Common Stock</securitiesClassTitle>
<eventDateRequiresFilingThisStatement>03/13/2026</eventDateRequiresFilingThisStatement>
<issuerInfo>
<issuerCik>0000866291</issuerCik>
<issuerName>Allegro MicroSystems Inc</issuerName>
<issuerCusips>
<issuerCusipNumber>01749D105</issuerCusipNumber>
</issuerCusips>
<issuerPrincipalExecutiveOfficeAddress>
<com:street1>955 Perimeter Road</com:street1>
<com:city>Manchester</com:city>
<com:stateOrCountry>NH</com:stateOrCountry>
<com:zipCode>03103</com:zipCode>
</issuerPrincipalExecutiveOfficeAddress>
</issuerInfo>
<designateRulesPursuantThisScheduleFiled>
<designateRulePursuantThisScheduleFiled>Rule 13d-1(b)</designateRulePursuantThisScheduleFiled>
</designateRulesPursuantThisScheduleFiled>
</coverPageHeader>
<coverPageHeaderReportingPersonDetails>
<reportingPersonName>The Vanguard Group</reportingPersonName>
<citizenshipOrOrganization>PA</citizenshipOrOrganization>
<reportingPersonBeneficiallyOwnedNumberOfShares>
<soleVotingPower>0</soleVotingPower>
<sharedVotingPower>0</sharedVotingPower>
<soleDispositivePower>0</soleDispositivePower>
<sharedDispositivePower>0</sharedDispositivePower>
</reportingPersonBeneficiallyOwnedNumberOfShares>
<reportingPersonBeneficiallyOwnedAggregateNumberOfShares>0</reportingPersonBeneficiallyOwnedAggregateNumberOfShares>
<classPercent>0</classPercent>
<typeOfReportingPerson>IA</typeOfReportingPerson>
<comments>
On January 12, 2026, The Vanguard Group, Inc. went through an internal realignment. In accordance with SEC Release No. 34-39538 (January 12, 1998), certain subsidiaries or business divisions of subsidiaries of The Vanguard Group, Inc., that formerly had, or were deemed to have, beneficial ownership with The Vanguard Group, Inc., will report beneficial ownership separately (on a disaggregated basis) from The Vanguard Group, Inc. in reliance on such release. These subsidiaries and/or business divisions pursue the same investment strategies as previously pursued by The Vanguard Group, Inc. prior to the realignment. Further in accordance with SEC Release No. 34-39538 (January 12, 1998), The Vanguard Group, Inc. no longer has, or is deemed to have, beneficial ownership over securities beneficially owned by such subsidiaries and/or business divisions.

</comments>
</coverPageHeaderReportingPersonDetails>
<items>
<item1>
<issuerName>Allegro MicroSystems Inc</issuerName>
<issuerPrincipalExecutiveOfficeAddress>955 Perimeter Road, Manchester, NH, 03103</issuerPrincipalExecutiveOfficeAddress>
</item1>
<item2>
<filingPersonName>The Vanguard Group</filingPersonName>
<principalBusinessOfficeOrResidenceAddress>100 Vanguard Blvd.,, Malvern, PA, 19355</principalBusinessOfficeOrResidenceAddress>
<citizenship>PA</citizenship>
</item2>
<item3>
<notApplicableFlag>N</notApplicableFlag>
<typeOfPersonFiling>IA</typeOfPersonFiling>
</item3>
<item4>
<amountBeneficiallyOwned>0</amountBeneficiallyOwned>
<classPercent>0</classPercent>
<numberOfSharesPersonHas>
<solePowerOrDirectToVote>0</solePowerOrDirectToVote>
<sharedPowerOrDirectToVote>0</sharedPowerOrDirectToVote>
<solePowerOrDirectToDispose>0</solePowerOrDirectToDispose>
<sharedPowerOrDirectToDispose>0</sharedPowerOrDirectToDispose>
</numberOfSharesPersonHas>
</item4>
<item5>
<notApplicableFlag>N</notApplicableFlag>
<classOwnership5PercentOrLess>Y</classOwnership5PercentOrLess>
</item5>
<item6>
<notApplicableFlag>N</notApplicableFlag>
<ownershipMoreThan5PercentOnBehalfOfAnotherPerson>The Vanguard Group, including investment companies registered under the Investment Company Act of 1940 and other managed accounts, have the right to receive or the power to direct the receipt of dividends from, or the proceeds from the sale of, the securities reported herein.No one other person's interest in the securities reported herein is more than 5%.</ownershipMoreThan5PercentOnBehalfOfAnotherPerson>
</item6>
<item7>
<notApplicableFlag>Y</notApplicableFlag>
</item7>
<item8>
<notApplicableFlag>Y</notApplicableFlag>
</item8>
<item9>
<notApplicableFlag>Y</notApplicableFlag>
</item9>
<item10>
<notApplicableFlag>N</notApplicableFlag>
<certifications>By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were acquired and are held in the ordinary course of business and were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect, other than activities solely in connection with a nomination under &amp;#167; 240.14a-11.</certifications>
</item10>
</items>
<signatureInformation>
<reportingPersonName>The Vanguard Group</reportingPersonName>
<signatureDetails>
<signature>Ashley Grim</signature>
<title>Head of Global Fund Administration</title>
<date>03/26/2026</date>
</signatureDetails>
</signatureInformation>
</formData>
</edgarSubmission>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
