Allegro MicroSystems, Inc.
MX ˙ BMV ˙ US01749D1054
SecurityMX:ALGM / Allegro MicroSystems, Inc.
InstitutionRussell Investments Group, Ltd.
Latest Disclosed Ownership96,083 shares
Latest Disclosed Value $ 3,029,495
Russell Investments Group, Ltd. reports 352.18% increase in ownership of ALGM / Allegro MicroSystems, Inc.

On May 8, 2026 - Russell Investments Group, Ltd. filed a 13F-HR form disclosing ownership of 96,083 shares of Allegro MicroSystems, Inc. (MX:ALGM) valued at $3,029,495 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 17, 2026 disclosing 21,249 shares of Allegro MicroSystems, Inc.. This represents a change in shares of 352.18% during the quarter.

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)
2026-05-08 2026-03-31 13F ALLEGRO MICROSYSTEMS INC COM Common Stock 01749D105 96,083 74,834 352.18 3,029 440.89 0.0003
2026-02-17 2025-12-31 13F ALLEGRO MICROSYSTEMS INC COM Common Stock 01749D105 21,249 6,753 46.59 561 32.39 0.0006
2025-11-13 2025-09-30 13F ALLEGRO MICROSYSTEMS INC COM Common Stock 01749D105 14,496 2,853 24.50 423 6.28 0.0005
2025-08-13 2025-06-30 13F ALLEGRO MICROSYSTEMS INC COM Common Stock 01749D105 11,643 -848 -6.79 398 27.16 0.0005
2025-05-13 2025-03-31 13F ALLEGRO MICROSYSTEMS INC COM Common Stock 01749D105 12,491 1,892 17.85 314 35.50 0.0004
2025-02-13 2024-12-31 13F ALLEGRO MICROSYSTEMS INC COM Common Stock 01749D105 10,599 -64,220 -85.83 232 -86.75 0.0003
2024-11-13 2024-09-30 13F ALLEGRO MICROSYSTEMS INC COM Common Stock 01749D105 74,819 20,647 38.11 1,743 14.00 0.0025
2024-08-08 2024-06-30 13F ALLEGRO MICROSYSTEMS INC COM Common Stock 01749D105 54,172 -1,562 -2.80 1,530 1.80 0.0025
2024-05-08 2024-03-31 13F ALLEGRO MICROSYSTEMS INC COM Common Stock 01749D105 55,734 39,289 238.91 1,503 202.21 0.0024
2024-02-05 2023-12-31 13F ALLEGRO MICROSYSTEMS INC COM Common Stock 01749D105 16,445 -8,304 -33.55 498 -37.09 0.0009
2023-11-13 2023-09-30 13F ALLEGRO MICROSYSTEMS INC COM Common Stock 01749D105 24,749 -21,689 -46.71 790 -62.31 0.0016
2023-08-10 2023-06-30 13F ALLEGRO MICROSYSTEMS INC COM Common Stock 01749D105 46,438 14,792 46.74 2,096 38.08 0.0040
2023-05-09 2023-03-31 13F ALLEGRO MICROSYSTEMS INC COM Common Stock 01749D105 31,646 -18,844 -37.32 1,519 0.20 0.0030
2023-02-08 2022-12-31 13F Sanken Electric Common Stock 01749D105 50,490 43,310 603.20 1,516 871.15 0.0031
2022-11-04 2022-09-30 13F Sanken Electric Common Stock 01749D105 7,180 7,180 156 0.0003
2022-07-29 2022-06-30 13F Sanken Electric Common Stock 01749D105 0 -4,400 -100.00 0 -100.00
2022-05-05 2022-03-31 13F Sanken Electric Common Stock 01749D105 4,400 -16,100 -78.54 124 -83.27 0.0002
2022-01-21 2021-12-31 13F Sanken Electric Common Stock 01749D105 20,500 8,542 71.43 741 93.98 0.0012
2021-11-08 2021-09-30 13F Sanken Electric Common Stock 01749D105 11,958 1,670 16.23 382 34.51 0.0006
2021-08-04 2021-06-30 13F Sanken Electric Common Stock 01749D105 10,288 -50,412 -83.05 284 -81.53 0.0005
2021-05-10 2021-03-31 13F ALLEGRO MICROSYSTEMS Common Stock 01749D105 60,700 60,700 1,538 0.0027
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.