    <SEC-DOCUMENT>0000950170-25-089737-index.html : 20250625
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    <ACCEPTANCE-DATETIME>20250625074036
    ACCESSION NUMBER:		0000950170-25-089737
    CONFORMED SUBMISSION TYPE:	DEFA14A
    PUBLIC DOCUMENT COUNT:		3
    FILED AS OF DATE:		20250625
    DATE AS OF CHANGE:		20250625

    FILER:

    	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:		DEFA14A
    		SEC ACT:		1934 Act
    		SEC FILE NUMBER:	001-39675
    		FILM NUMBER:		251070979

    	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
    </SEC-HEADER>
    <DOCUMENT>
    <TYPE>DEFA14A
    <SEQUENCE>1
    <FILENAME>algm_2025_proxy_addtl_ma.htm
    <DESCRIPTION>DEFA14A
    <TEXT>
    Document 1 - file: algm_2025_proxy_addtl_ma.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>2
    <FILENAME>img186737531_0.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 2 - file: img186737531_0.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>3
    <FILENAME>img186737531_1.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 3 - file: img186737531_1.jpg

    </DOCUMENT>
    </SEC-DOCUMENT>