Allegro MicroSystems, Inc.
MX ˙ BMV ˙ US01749D1054
SecurityMX:ALGM / Allegro MicroSystems, Inc.
InstitutionAcadian Asset Management Llc
Latest Disclosed Ownership13,881 shares
Latest Disclosed Value $ 437
Acadian Asset Management Llc reports 188.77% increase in ownership of ALGM / Allegro MicroSystems, Inc.

On May 13, 2026 - Acadian Asset Management Llc filed a 13F-HR form disclosing ownership of 13,881 shares of Allegro MicroSystems, Inc. (MX:ALGM) valued at $437 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 10, 2026 disclosing 4,807 shares of Allegro MicroSystems, Inc..

Institutional Ownership: 13F and NPORT Filings

The Security and Class in the table below are shown exactly as filed by the investor. We do our best to track continuity of investments through acquisitions, and this will be reflected in the table as changes in names. In addition to descriptive data, performance of the investment is shown over time. To calculate quarterly performance, we first calculate cost basis of the shares purchased during the quarter, then use that to calculate gross profit. Quarterly return is Gross Profit / Starting Portfolio value.

Note that cost basis is calculated and stored in thousands, so small quarterly changes in shares frequently result in a cost basis of zero.

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Disclosed Equity Positions (from 13F/NPORT Filings)
File
Date
Effective
Date
Form Security Class ID Avg Price
Paid (Est)
Reported
Shares
ΔShares ΔShares
(%)
Reported
Value
(x1000)
ΔValue
(%)
Alloc
(%)
ΔAlloc ΔAlloc (%) Cost Basis
(x1000)
Unrealized
Gain/Loss
(x1000)
2026-05-13 2026-03-31 13F ALLEGRO MICROSYSTEMS COM 01749D105 13,881 9,074 188.77 0 0.0006
2026-02-10 2025-12-31 13F ALLEGRO MICROSYSTEMS COM 01749D105 4,807 -43,433 -90.04 0 -100.00 0.0002
2025-11-13 2025-09-30 13F ALLEGRO MICROSYSTEMS COM 01749D105 48,240 48,240 1 0.0025
2023-11-13 2023-09-30 13F ALLEGRO MICROSYSTEMS COM 01749D105 0 -1,821 -100.00 0 0.0000
2023-08-07 2023-06-30 13F ALLEGRO MICROSYSTEMS COM 01749D105 1,821 0 0.00 0 0.0003
2023-05-11 2023-03-31 13F ALLEGRO MICROSYSTEMS COM 01749D105 1,821 0 0.00 0 0.0004
2023-02-14 2022-12-31 13F ALLEGRO MICROSYSTEMS COM 01749D105 1,821 1,821 0 0.0003
2022-05-12 2022-03-31 13F ALLEGRO MICROSYSTEMS COM 01749D105 0 -11,880 -100.00 0 -100.00
2022-02-10 2021-12-31 13F ALLEGRO MICROSYSTEMS COM 01749D105 11,880 11,880 429 0.0016
2021-08-11 2021-06-30 13F ALLEGRO MICROSYSTEMS COM 01749D105 0 -3,859 -100.00 0 -100.00
2021-05-11 2021-03-31 13F ALLEGRO MICROSYSTEMS COM 01749D105 3,859 3,859 98 0.0004
Legend
Shares
The total number of shares held by the institution at the end of the reporting period (the effective date). This is provided in the filing.
Value
The total value of the shares as of the effective date. This is provided in the filing.
Avg. Share Price
The weighted average share price of the shares held by the institution. We use FIFO accounting to determine this price
Class
This is the security class as indicated by the filer. There are a variety of values for this field. Common values include "EC" = equity common, "EP" - equity preferred
Allocation (%)
The percent of the institution's portfolio that this position represents. This is provided in NPORT filings. For 13F filings, we calculate it.
Change in Allocation
The change in allocation from the prior reporting period. This is calculated as current allocation - prior allocation.
Change in Allocation (%)
The percent change in allocation from the prior reporting period. This is calculated as (current allocation - prior allocation) / prior allocation.
Cost Basis
The total cost of the shares held. This is calculated as reported shares * avg. share price
Unrealized Gain/Loss
This is the market value of the position as of the effective date minus the cost basis.