Bel Fuse Inc.

SecurityBELFB / Bel Fuse Inc.
InstitutionNorthern Trust Corp
Latest Disclosed Ownership104,880 shares
Latest Disclosed Value $ 20,764,142
Northern Trust Corp reports 3.90% increase in ownership of BELFB / Bel Fuse Inc.

On May 14, 2026 - Northern Trust Corp filed a 13F-HR form disclosing ownership of 104,880 shares of Bel Fuse Inc. (US:BELFB) valued at $20,764,142 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 17, 2026 disclosing 100,940 shares of Bel Fuse Inc.. This represents a change in shares of 3.90% during the quarter. The current value of the position is $27,537,293 USD.

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)
2026-05-14 2026-03-31 13F BEL FUSE CL B 077347300 104,880 3,940 3.90 20,764 21.27 0.0006
2026-02-17 2025-12-31 13F BEL FUSE CL B 077347300 100,940 -7,148 -6.61 17,122 12.33 0.0005
2025-11-14 2025-09-30 13F BEL FUSE CL B 077347300 108,088 -231 -0.21 15,243 44.05 0.0004
2025-08-13 2025-06-30 13F BEL FUSE CL B 077347300 108,319 -2,573 -2.32 10,582 27.47 0.0015
2025-05-13 2025-03-31 13F BEL FUSE CL B 077347300 110,892 -4,611 -3.99 8,301 -12.85 0.0012
2025-02-14 2024-12-31 13F BEL FUSE CL B 077347300 115,503 12,307 11.93 9,526 17.58 0.0013
2024-11-13 2024-09-30 13F BEL FUSE COM 077347300 103,196 3,124 3.12 8,102 24.10 0.0013
2024-08-14 2024-06-30 13F BEL FUSE COM 077347300 100,072 -4,345 -4.16 6,529 3.67 0.0011
2024-05-14 2024-03-31 13F BEL FUSE COM 077347300 104,417 -1,874 -1.76 6,297 -11.27 0.0011
2024-02-13 2023-12-31 13F BEL FUSE COM 077347300 106,291 2,140 2.05 7,097 42.80 0.0013
2023-11-13 2023-09-30 13F BEL FUSE COM 077347300 104,151 3,001 2.97 4,970 -14.41 0.0010
2023-08-11 2023-06-30 13F BEL FUSE COM 077347300 101,150 71,071 236.28 5,807 413.89 0.0011
2023-05-15 2023-03-31 13F BEL FUSE COM 077347300 30,079 216 0.72 1,130 14.95 0.0002
2023-02-13 2022-12-31 13F BEL FUSE COM 077347300 29,863 -1,602 -5.09 983 23.65 0.0002
2022-11-14 2022-09-30 13F BEL FUSE COM 077347300 31,465 65 0.21 795 62.91 0.0002
2022-08-12 2022-06-30 13F BEL FUSE COM 077347300 31,400 -80 -0.25 488 -13.17 0.0001
2022-05-13 2022-03-31 13F BEL FUSE COM 077347300 31,480 -1,326 -4.04 562 32.55 0.0001
2022-02-08 2021-12-31 13F BEL FUSE COM 077347300 32,806 -1,816 -5.25 424 -1.40 0.0001
2021-11-15 2021-09-30 13F BEL FUSE COM 077347300 34,622 -7,976 -18.72 430 -29.97 0.0001
2021-08-13 2021-06-30 13F BEL FUSE COM 077347300 42,598 -77,853 -64.63 614 -74.37 0.0001
2021-05-12 2021-03-31 13F BEL FUSE CL B 077347300 120,451 -11,599 -8.78 2,396 20.71 0.0004
2021-02-11 2020-12-31 13F BEL FUSE CL B 077347300 132,050 -7,108 -5.11 1,985 33.58 0.0004
2020-11-16 2020-09-30 13F BEL FUSE CL B 077347300 139,158 -3,531 -2.47 1,486 -2.94 0.0003
2020-08-14 2020-06-30 13F BEL FUSE COM 077347300 142,689 3,529 2.54 1,531 12.91 0.0004
2020-05-14 2020-03-31 13F BEL FUSE CL B 077347300 139,160 9,696 7.49 1,356 -48.93 0.0004
2020-02-14 2019-12-31 13F BEL FUSE COM 077347300 129,464 -7,898 -5.75 2,655 28.63 0.0006
2019-11-13 2019-09-30 13F BEL FUSE COM 077347300 137,362 -14,303 -9.43 2,064 -20.74 0.0005
2019-08-13 2019-06-30 13F BEL FUSE COM 077347300 151,665 -1,196 -0.78 2,604 -32.61 0.0006
2019-05-13 2019-03-31 13F BEL FUSE CL B 077347300 152,861 4,369 2.94 3,864 41.28 0.0010
2019-02-12 2018-12-31 13F BEL FUSE CL B 077347300 148,492 -874 -0.59 2,735 -30.90 0.0008
2018-11-14 2018-09-30 13F BEL FUSE CL B 077347300 149,366 1,685 1.14 3,958 28.26 0.0010
2018-09-18 2018-06-30 13F/A-1 BEL FUSE CL B 077347300 147,681 -2,689 -1.79 3,086 8.59 0.0008
2018-08-14 2018-06-30 13F BEL FUSE CL B 077347300 148,472 -1,898 3,103
2018-05-09 2018-03-31 13F BEL FUSE CL B 077347300 150,370 -1,143 -0.75 2,842 -25.50 0.0007
2018-02-14 2017-12-31 13F BEL FUSE CL B 077347300 151,513 1,142 0.76 3,815 -18.67 0.0010
2017-11-13 2017-09-30 13F BEL FUSE CL B 077347300 150,371 2,636 1.78 4,691 28.56 0.0012
2017-08-11 2017-06-30 13F BEL FUSE COM 077347300 147,735 9,045 6.52 3,649 2.96 0.0010
2017-05-12 2017-03-31 13F BEL FUSE COM 077347300 138,690 -2,122 -1.51 3,544 -18.57 0.0010
2017-02-13 2016-12-31 13F BEL FUSE COM 077347300 140,812 4,082 2.99 4,352 31.84 0.0013
2016-11-09 2016-09-30 13F BEL FUSE COM 077347300 136,730 6,693 5.15 3,301 42.78 0.0010
2016-08-12 2016-06-30 13F BEL FUSE COM 077347300 130,037 3,936 3.12 2,312 24.23 0.0008
2016-08-19 2016-03-31 13F/A-1 BEL FUSE CL B 077347300 126,101 790 0.63 1,861 -14.08 0.0006
2016-05-13 2016-03-31 13F Bel Fuse COMM 077347300 126,101 1,841
2016-02-12 2015-12-31 13F Bel Fuse COMM 077347300 125,311 473 0.38 2,166 -10.75 0.0007
2015-11-12 2015-09-30 13F Bel Fuse COMM 077347300 124,838 -6,717 -5.11 2,427 -10.08 0.0008
2015-08-13 2015-06-30 13F BEL FUSE COM 077347300 131,555 8,248 6.69 2,699 15.05 0.0018
2015-05-14 2015-03-31 13F Bel Fuse COMM 077347300 123,307 2,259 1.87 2,346 -29.12 0.0007
2015-02-12 2014-12-31 13F BEL FUSE COM 077347300 121,048 -5,722 -4.51 3,310 5.55 0.0010
2014-11-13 2014-09-30 13F Bel Fuse COMM 077347300 126,770 -5,969 -4.50 3,136 -7.98 0.0010
2014-08-14 2014-06-30 13F BEL FUSE com 077347300 132,739 -15,993 -10.75 3,408 4.64 0.0011
2014-05-14 2014-03-31 13F BEL FUSE COMM 077347300 148,732 -6,997 -4.49 3,257 -1.84 0.0010
2014-02-21 2013-12-31 13F/A-1 BEL FUSE COM 077347300 155,729 -2,853 -1.80 3,318 19.96 0.0011
2014-02-12 2013-12-31 13F BEL FUSE COM 077347300 155,729 3,318
2013-11-13 2013-09-30 13F BEL FUSE COM 077347300 158,582 13,314 9.17 2,766 41.63 0.0010
2013-08-09 2013-06-30 13F BEL FUSE COM 077347300 145,268 145,268 1,953 0.0007
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.