Bel Fuse Inc.
US ˙ NasdaqGS ˙ US0773472016

SecurityBELFA / Bel Fuse Inc.
InstitutionRenaissance Technologies Llc
ManagerJames Simons
Latest Disclosed Ownership68,253 shares
Latest Disclosed Value $ 12,299,191
Renaissance Technologies Llc reports 62.30% increase in ownership of BELFA / Bel Fuse Inc.

On May 14, 2026 - Renaissance Technologies Llc filed a 13F-HR form disclosing ownership of 68,253 shares of Bel Fuse Inc. (US:BELFA) valued at $12,299,191 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 12, 2026 disclosing 42,053 shares of Bel Fuse Inc.. This represents a change in shares of 62.30% during the quarter. The current value of the position is $15,837,426 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 A 077347201 68,253 26,200 62.30 12,299 92.68 0.0192
2026-02-12 2025-12-31 13F BEL FUSE CL A 077347201 42,053 -700 -1.64 6,384 28.33 0.0099
2025-11-13 2025-09-30 13F BEL FUSE CL A 077347201 42,753 300 0.71 4,974 30.41 0.0066
2025-08-13 2025-06-30 13F BEL FUSE CL A 077347201 42,453 -300 -0.70 3,814 23.83 0.0051
2025-05-14 2025-03-31 13F BEL FUSE CL A 077347201 42,753 -500 -1.16 3,081 -20.94 0.0047
2025-02-13 2024-12-31 13F BEL FUSE CL A 077347201 43,253 1,300 3.10 3,896 -6.59 0.0058
2024-11-13 2024-09-30 13F BEL FUSE CL A 077347201 41,953 7,600 22.12 4,171 50.09 0.0063
2024-08-09 2024-06-30 13F BEL FUSE CL A 077347201 34,353 -1,147 -3.23 2,780 138,850.00 0.0047
2024-05-13 2024-03-31 13F BEL FUSE CL A 077347201 35,500 2,200 6.61 3 0.00 0.0040
2024-02-13 2023-12-31 13F BEL FUSE CL A 077347201 33,300 1,100 3.42 2 100.00 0.0033
2023-11-14 2023-09-30 13F BEL FUSE CL A 077347201 32,200 4,600 16.67 2 0.00 0.0026
2023-08-11 2023-06-30 13F BEL FUSE CL A 077347201 27,600 1,400 5.34 2 0.0023
2023-05-12 2023-03-31 13F BEL FUSE CL A 077347201 26,200 1,600 6.50 1 0.0013
2023-02-13 2022-12-31 13F BEL FUSE CL A 077347201 24,600 2,300 10.31 1 -100.00 0.0011
2022-11-14 2022-09-30 13F BEL FUSE CL A 077347201 22,300 -2,100 -8.61 623 18.67 0.0009
2022-08-12 2022-06-30 13F BEL FUSE CL A 077347201 24,400 600 2.52 525 5.00 0.0006
2022-05-13 2022-03-31 13F BEL FUSE CL A 077347201 23,800 -200 -0.83 500 38.89 0.0006
2022-02-11 2021-12-31 13F BEL FUSE CL A 077347201 24,000 -4,100 -14.59 360 -11.55 0.0004
2021-11-12 2021-09-30 13F BEL FUSE CL A 077347201 28,100 -400 -1.40 407 0.74 0.0005
2021-08-13 2021-06-30 13F BEL FUSE CL A 077347201 28,500 2,500 9.62 404 -16.53 0.0005
2021-05-13 2021-03-31 13F BEL FUSE CL A 077347201 26,000 -1,100 -4.06 484 34.44 0.0006
2021-02-10 2020-12-31 13F BEL FUSE CL A 077347201 27,100 1,300 5.04 360 19.21 0.0004
2020-11-13 2020-09-30 13F BEL FUSE CL A 077347201 25,800 700 2.79 302 19.84 0.0003
2020-08-13 2020-06-30 13F BEL FUSE CL A 077347201 25,100 500 2.03 252 35.48 0.0002
2020-05-14 2020-03-31 13F BEL FUSE CL A 077347201 24,600 600 2.50 186 -52.19 0.0002
2020-02-13 2019-12-31 13F BEL FUSE CL A 077347201 24,000 1,800 8.11 389 27.12 0.0003
2019-11-13 2019-09-30 13F BEL FUSE CL A 077347201 22,200 800 3.74 306 -6.13 0.0003
2019-08-12 2019-06-30 13F BEL FUSE CL A 077347201 21,400 200 0.94 326 -28.19 0.0003
2019-05-14 2019-03-31 13F BEL FUSE CL A 077347201 21,200 300 1.44 454 58.19 0.0004
2019-02-12 2018-12-31 13F BEL FUSE CL A 077347201 20,900 300 1.46 287 -35.36 0.0003
2018-11-13 2018-09-30 13F BEL FUSE CL A 077347201 20,600 100 0.49 444 3.74 0.0005
2018-08-13 2018-06-30 13F/A-1 BEL FUSE CL A 077347201 20,500 -600 -2.84 428 19.22 0.0005
2018-08-13 2018-06-30 13F BEL FUSE CL A 077347201 21,100 359
2018-05-14 2018-03-31 13F BEL FUSE CL A 077347201 21,100 0 0.00 359 -21.96 0.0004
2018-02-13 2017-12-31 13F BEL FUSE CL A 077347201 21,100 900 4.46 460 -16.21 0.0005
2017-11-13 2017-09-30 13F BEL FUSE CL A 077347201 20,200 200 1.00 549 32.61 0.0006
2017-08-11 2017-06-30 13F BEL FUSE CL A 077347201 20,000 0 0.00 414 -8.61 0.0005
2017-05-12 2017-03-31 13F BEL FUSE CL A 077347201 20,000 400 2.04 453 -8.67 0.0006
2017-02-13 2016-12-31 13F BEL FUSE CL A 077347201 19,600 1,900 10.73 496 38.94 0.0008
2016-11-14 2016-09-30 13F BEL FUSE CL A 077347201 17,700 400 2.31 357 31.73 0.0006
2016-08-12 2016-06-30 13F BEL FUSE CL A 077347201 17,300 0 0.00 271 14.83 0.0005
2016-05-13 2016-03-31 13F BEL FUSE CL A 077347201 17,300 0 0.00 236 -7.09 0.0004
2016-02-11 2015-12-31 13F BEL FUSE CL A 077347201 17,300 -200 -1.14 254 -12.11 0.0006
2015-11-12 2015-09-30 13F BEL FUSE CL A 077347201 17,500 0 0.00 289 -15.00 0.0007
2015-08-14 2015-06-30 13F BEL FUSE CL A 077347201 17,500 400 2.34 340 8.63 0.0008
2015-05-13 2015-03-31 13F BEL FUSE CL A 077347201 17,100 500 3.01 313 -21.36 0.0007
2015-02-13 2014-12-31 13F BEL FUSE CL A 077347201 16,600 500 3.11 398 1.79 0.0010
2014-11-12 2014-09-30 13F BEL FUSE CL A 077347201 16,100 400 2.55 391 1.30 0.0011
2014-08-13 2014-06-30 13F BEL FUSE CL A 077347201 15,700 600 3.97 386 32.19 0.0009
2014-05-14 2014-03-31 13F BEL FUSE CL A 077347201 15,100 -200 -1.31 292 -1.68 0.0007
2014-02-14 2013-12-31 13F BEL FUSE CL A 077347201 15,300 -300 -1.92 297 10.00 0.0007
2013-11-13 2013-09-30 13F BEL FUSE CL A 077347201 15,600 -200 -1.27 270 22.17 0.0007
2013-08-12 2013-06-30 13F BEL FUSE CL A 077347201 15,800 15,800 221 0.0006
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.