ALLEGRO MICROSYSTEMS INC

Trading Arrangements

During the fiscal quarter ended March 29, 2024, none of our directors or officers informed us of theadoption, modification ortermination of a “Rule 10b5-1 trading arrangement” or “non-Rule 10b5-1 trading arrangement,” as those terms are defined in Regulation S-K, Item 408.

Annual Incentive Plan

On May 20, 2024, the Compensation Committee of the Company’s Board of Directors (the “Compensation Committee”) adopted the Allegro MicroSystems, Inc. Annual Incentive Plan (the “AIP”), a plan adopted under and pursuant to the Allegro MicroSystems, Inc. 2020 Omnibus Incentive Compensation Plan (the “2020 Plan”). The AIP is effective beginning with the Company’s 2025 fiscal year and provides for the payment of annual incentive compensation to eligible AIP participants in the form of cash bonuses determined on a fiscal year basis as rewards for achieving annual performance metrics.

Administration. The AIP is administered by the Compensation Committee and, with respect to eligible participants who are not officers for Section 16(b) of the Exchange Act, by a committee of the Company’s officers to whom the Compensation Committee has delegated administrative authority.

Eligibility. The Compensation Committee will select the participants that are eligible to receive bonuses under the AIP for each fiscal year. Any employee of the Company or one of its subsidiaries who is not eligible to receive variable compensation under a separate plan, program or arrangement may be eligible to receive a bonus under the AIP for a given fiscal year, if selected by the

Compensation Committee. Each of the Company’s executive officers, including its named executive officers, are participants in the AIP.

Award Pool. Under the AIP, the Compensation Committee will establish a target award pool for each fiscal year based on the aggregate target bonus opportunities of all eligible participants for such fiscal year, as adjusted for changes in eligible participants throughout the fiscal year. Individual target bonus opportunities are based on a percentage of the applicable participant’s base salary. Following the end of each fiscal year, the Compensation Committee will make a final adjustment to the award pool by multiplying the target award pool by the weighted average achievement of each performance metric established for such fiscal year. In no event shall the final adjustments made as a result of achievement of the performance metrics for a fiscal year exceed 200% of the award pool, regardless of the performance of the performance metrics during the applicable fiscal year. The Compensation Committee has the discretion to make further adjustments to the final award pool to account for unanticipated business conditions, extraordinary events or other factors that the Compensation Committee may consider.

Performance Metrics. The Compensation Committee is responsible for setting the performance metrics each fiscal year and certifying the Company’s performance relative to such performance metrics following the conclusion of each fiscal year, as may be adjusted under certain circumstances specified in the AIP. Performance metrics may include a threshold level of performance below which no bonuses will be paid, levels of performance at which specified percentages of the target bonus may be paid and a maximum level of performance above which no additional bonus will be paid. Bonus payouts to participants that are officers for purposes of Section 16(b) of the Exchange Act may not exceed 200% of their respective target bonus opportunities under the AIP. Performance metrics will be based on objectively determinable goals based upon one or more financial, operational or strategic measures determined at the discretion of the Compensation Committee, and performance metrics may carry different weighting.

Bonus Payouts; Clawback. Bonuses for a given fiscal year will be paid, to the extent earned, within 100 days following the Compensation Committee’s certification of achievement of the applicable performance metrics following the end of such fiscal year, subject to the applicable participant’s continued employment through the date of payout. The Compensation Committee may determine, in its sole discretion, to pay a pro-rated bonus to a participant who was employed for at least 50% of the applicable fiscal year and whose employment terminated prior to the date of payout. The Compensation Committee may determine to make such pro-rated payout subject to such participant’s execution and delivery of an effective release of claims in favor of the Company and its affiliates. In addition, payouts under the AIP are subject to the Company’s Policy for Recovery of Erroneously Awarded Compensation.

Change of Control. In the event of a Change of Control (as defined in the 2020 Plan) prior to the end of a given fiscal year, such fiscal year will be deemed to end on the date of such Change of Control and the performance metrics for such fiscal year will be deemed to have been achieved at the greater of target or actual performance for the shortened fiscal year, with bonus payouts being pro-rated for the shortened fiscal year. In the event of a Change of Control following the end of a given fiscal year but prior to the payout of bonuses for such fiscal year, the performance metrics for such fiscal year will be determined based on the actual performance for the full fiscal year, and bonus payouts will be made in respect of the full fiscal year.

The above description of the AIP does not purport to be complete and is included solely as a summary of the material terms of the AIP, a copy of which is filed as Exhibit 10.9 to this Annual Report on Form 10-K and is incorporated by reference.

Compensatory Arrangement with Michael Doogue

In connection with Michael Doogue’s, the Company’s SVP and Chief Technology Officer, foreign assignment to the Company’s offices in France for approximately nine months (the “Assignment”), on May 20, 2024, the Company’s Compensation Committee approved a one-time bonus of $139,000 to compensate Mr. Doogue for travel, relocation and other costs incurred in connection with the Assignment, and tax equalization payments by the Company of up to $200,000 to ensure that the income and employment tax burden incurred by Mr. Doogue during the Assignment is not substantially greater or less than the tax that he would have paid if he had performed all of his duties in the United States. The one-time bonus will be paid in biweekly installments beginning on June 1, 2024 through the end of the Company’s 2025 fiscal year. For the tax equalization payments, the Company will withhold a hypothetical tax from Mr. Doogue’s employment compensation that will reflect more or less what he would have paid had he remained working in the United States, and the Company will use such hypothetical withholdings and up to an additional $200,000 to fund all actual taxes required to be paid to the applicable domestic and foreign tax authorities over the course of four years.