Allegro MicroSystems (ALGM) officer sells 27,873 shares under 10b5-1 plan

Rhea-AI Filing Summary

Allegro MicroSystems, Inc. disclosed that its SVP, GC and Secretary, Sharon S. Briansky, sold 27,873 shares of common stock on 12/10/2025 at $30 per share. After this disposition, she beneficially owned 121,263 shares directly.

The transaction was carried out under a Rule 10b5-1 trading plan adopted on August 4, 2025, with details of that plan previously described in the company’s Quarterly Report on Form 10-Q for the period ended September 26, 2025, which was filed on October 31, 2025.

SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0287
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Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

Briansky Sharon

(Last) (First) (Middle)

955 PERIMETER ROAD

(Street)

MANCHESTER NH 03103

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
ALLEGRO MICROSYSTEMS, INC. [ ALGM ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	SVP, GC and Secretary

3. Date of Earliest Transaction (Month/Day/Year)
12/10/2025

4. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Stock	12/10/2025		S(1)		27,873	D	$30	121,263	D

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

Explanation of Responses:

1. The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on August 4, 2025. Details regarding the Reporting Person's trading plan were reported in Part II, Item 5 of the Issuer's Quarterly Report on Form 10-Q for the period ending September 26, 2025, filed with the SEC on October 31, 2025.

	/s/ Raymond Myer, Attorney-in-Fact for Sharon S. Briansky	12/12/2025
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.

FAQ

What insider transaction did Allegro MicroSystems (ALGM) report in this filing?

Allegro MicroSystems reported that its SVP, GC and Secretary, Sharon S. Briansky, sold 27,873 shares of the company’s common stock on 12/10/2025.

At what price were the ALGM shares sold and how many shares remain held?

The shares were sold at $30 per share, and following the sale, Sharon S. Briansky beneficially owned 121,263 shares of Allegro MicroSystems common stock directly.

Was the Allegro MicroSystems (ALGM) insider sale under a Rule 10b5-1 trading plan?

Yes. The filing states that the sales were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on August 4, 2025.

When were details of the ALGM insider’s Rule 10b5-1 plan previously disclosed?

The filing notes that details of the trading plan were reported in Part II, Item 5 of Allegro MicroSystems’ Form 10-Q for the period ending September 26, 2025, filed on October 31, 2025.

What is Sharon S. Briansky’s role at Allegro MicroSystems (ALGM)?

The reporting person, Sharon S. Briansky, is identified as an officer of Allegro MicroSystems, serving as SVP, GC and Secretary.

Is this Allegro MicroSystems (ALGM) filing for one reporting person or a group?

The form indicates it is filed by one reporting person, not by more than one reporting person or a group.