Mesabi Trust
US ˙ NYSE ˙ US5906721015

SecurityMSB / Mesabi Trust
InstitutionGroup One Trading, L.p.
Latest Disclosed Ownership441 shares
Latest Disclosed Value $ 16,987
Group One Trading, L.p. ownership in MSB / Mesabi Trust

On February 11, 2026 - Group One Trading, L.p. filed a 13F-HR form disclosing ownership of 441 shares of Mesabi Trust (US:MSB) valued at $16,987 USD as of December 31, 2025. The entity filed a previous 13F-HR on November 12, 2025 disclosing 41 shares of Mesabi Trust. This represents a change in shares of 975.61% during the quarter. The current value of the position is $11,254 USD.

Group One Trading, L.p. has a history of taking positions in derivatives of the underlying security (MSB) in the form of stock options. The firm currently holds call options representing 0 of underlying shares valued at $0 USD .

Note: prior versions of this page mistakenly stated that the share values represented the number of options, not the number of underlying shares. For more information on the data backing these reports, please see the SEC document Frequently Asked Questions About Form 13F.

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.

Upgrade to unlock premium data and export to Excel .

Institutional Put/Call Ratios
(Premium Subscription Required)

In addition to reporting standard equity and debt issues, institutions with more than 100MM assets under management must also disclose their put and call option holdings. Since put options generally indicate negative sentiment, and call options indicate positive sentiment, we can get a sense of the overall institutional sentiment by plotting the ratio of puts to calls. The chart to the right plots the historical put/call ratio for this instrument.

Using Put/Call Ratio as an indicator of investor sentiment overcomes one of the key deficiencies of using total institutional ownership, which is that a significant amount of assets under management are invested passively to track indices. Passively-managed funds do not typically buy options, so the put/call ratio indicator more closely tracks the sentiment of actively-managed funds.

MSB / Mesabi Trust Historical Put/Call Ratio
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)
2026-02-11 2025-12-31 13F MESABI TR CTF BEN INT 590672101 441 400 975.61 17 1,500.00 0.0000
2025-11-12 2025-09-30 13F MESABI TR CTF BEN INT 590672101 41 41 1 0.0000
2024-08-14 2024-06-30 13F MESABI TR CTF BEN INT 590672101 0 -100 -100.00 0 -100.00
2024-05-10 2024-03-31 13F MESABI TR CTF BEN INT 590672101 100 0 0.00 2 -50.00 0.0000
2024-02-14 2023-12-31 13F MESABI TR CTF BEN INT 590672101 100 100 2 0.0000
2023-05-12 2023-03-31 13F MESABI TR CTF BEN INT 590672101 0 -979 -100.00 0 -100.00
2023-02-09 2022-12-31 13F MESABI TR CTF BEN INT 590672101 979 811 482.74 18 325.00 0.0000
2022-11-09 2022-09-30 13F MESABI TR CTF BEN INT 590672101 168 168 4 0.0000
2022-08-11 2022-06-30 13F MESABI TR CTF BEN INT 590672101 0 -568 -100.00 0 -100.00
2022-05-12 2022-03-31 13F MESABI TR CTF BEN INT 590672101 568 -867 -60.42 15 -60.53 0.0000
2022-02-11 2021-12-31 13F MESABI TR CTF BEN INT 590672101 1,435 -7,312 -83.59 38 -85.38 0.0000
2021-11-12 2021-09-30 13F MESABI TR CTF BEN INT 590672101 8,747 -5,000 -36.37 260 -46.61 0.0003
2021-08-10 2021-06-30 13F MESABI TR CTF BEN INT 590672101 13,747 13,747 487 0.0006
2021-02-10 2020-12-31 13F MESABI TR CTF BEN INT 590672101 0 -799 -100.00 0 -100.00
2020-11-12 2020-09-30 13F MESABI TR CTF BEN INT 590672101 799 703 732.29 17 750.00 0.0001
2020-08-13 2020-06-30 13F MESABI TR CTF BEN INT 590672101 96 96 -87.98 2 -88.24 0.0000
2019-05-14 2019-03-31 13F/A-1 MESABI TR CTF BEN INT 590672101 0 -2,362 -100.00 0 -100.00
2019-02-05 2018-12-31 13F MESABI TR CTF BEN INT 590672101 2,362 -7,483 -76.01 56 -78.54 0.0005
2018-11-08 2018-09-30 13F MESABI TR CTF BEN INT 590672101 9,845 -4,575 -31.73 261 -26.27 0.0021
2018-08-13 2018-06-30 13F MESABI TR CTF BEN INT 590672101 14,420 2,248 18.47 354 13.10 0.0030
2018-05-16 2018-03-31 13F/A-1 MESABI TR CTF BEN INT 590672101 12,172 7,646 168.94 313 174.56 0.0031
2018-05-10 2018-03-31 13F MESABI TR CTF BEN INT 590672101 12,172 7,646 313
2018-02-09 2017-12-31 13F MESABI TR CTF BEN INT 590672101 4,526 4,526 -62.82 114 -63.58 0.0008
2016-08-12 2016-06-30 13F MESABI TR CTF BEN INT 590672101 0 -1,000 -100.00 0 -100.00
2016-05-12 2016-03-31 13F MESABI TR CTF BEN INT 590672101 1,000 600 150.00 6 200.00 0.0001
2016-02-11 2015-12-31 13F MESABI TR CTF BEN INT 590672101 400 300 300.00 2 100.00 0.0000
2015-11-20 2015-09-30 13F/A-1 MESABI TR CTF BEN INT 590672101 100 100 -75.00 1 -50.00 0.0000
2015-11-06 2015-09-30 13F MESABI TR CTF BEN INT 590672101 100 1
2015-02-11 2014-12-31 13F MESABI TR CTF BEN INT 590672101 0 -7,540 -100.00 0 -100.00
2014-10-31 2014-09-30 13F MESABI TR CTF BEN INT 590672101 7,540 108 1.45 144 -0.69 0.0022
2014-08-12 2014-06-30 13F MESABI TR CTF BEN INT 590672101 7,432 6,532 725.78 145 625.00 0.0022
2013-11-15 2013-09-30 13F MESABI TR CTF BEN INT 590672101 900 900 20 0.0004
Disclosed Call Options
File
Date
Effective
Date
Form Security Class ID Opt Avg Share
Price
Shares ΔShares
(%)
Value
(x1000)
ΔValue
(%)
Prior Allocation
(%)
Allocation
(%)
ΔAllocation
(%)
Cost Basis
(x1000)
Profit
(x1000)
Return
(%)
2026-02-11 2025-12-31 13F MESABI TR CTF BEN INT Call 0 -100.00 0 -100.00 n/a n/a n/a
2025-11-12 2025-09-30 13F MESABI TR CTF BEN INT Call 1,000 150.00 29 222.22 n/a n/a n/a
2025-08-14 2025-06-30 13F MESABI TR CTF BEN INT Call 400 0.00 10 -10.00 n/a n/a n/a
2025-05-14 2025-03-31 13F MESABI TR CTF BEN INT Call 400 11 n/a n/a n/a
2024-11-14 2024-09-30 13F MESABI TR CTF BEN INT Call 0 -100.00 0 -100.00 n/a n/a n/a
2024-08-14 2024-06-30 13F MESABI TR CTF BEN INT Call 300 -80.00 5 -80.77 n/a n/a n/a
2024-05-10 2024-03-31 13F MESABI TR CTF BEN INT Call 1,500 36.36 27 18.18 n/a n/a n/a
2024-02-14 2023-12-31 13F MESABI TR CTF BEN INT Call 1,100 1,000.00 23 1,000.00 n/a n/a n/a
2023-11-09 2023-09-30 13F MESABI TR CTF BEN INT Call 100 -66.67 2 -66.67 n/a n/a n/a
2023-08-09 2023-06-30 13F MESABI TR CTF BEN INT Call 300 -25.00 6 -40.00 n/a n/a n/a
2023-05-12 2023-03-31 13F MESABI TR CTF BEN INT Call 400 10 n/a n/a n/a
2023-02-09 2022-12-31 13F MESABI TR CTF BEN INT Call 0 -100.00 0 -100.00 n/a n/a n/a
2022-11-09 2022-09-30 13F MESABI TR CTF BEN INT Call 1,000 22 n/a n/a n/a
2022-08-11 2022-06-30 13F MESABI TR CTF BEN INT Call 0 -100.00 0 -100.00 n/a n/a n/a
2022-05-12 2022-03-31 13F MESABI TR CTF BEN INT Call 600 -77.78 16 -77.46 n/a n/a n/a
2022-02-11 2021-12-31 13F MESABI TR CTF BEN INT Call 2,700 -63.51 71 -67.73 n/a n/a n/a
2021-11-12 2021-09-30 13F MESABI TR CTF BEN INT Call 7,400 393.33 220 315.09 n/a n/a n/a
2021-08-10 2021-06-30 13F MESABI TR CTF BEN INT Call 1,500 50.00 53 76.67 n/a n/a n/a
2021-05-12 2021-03-31 13F MESABI TR CTF BEN INT Call 1,000 233.33 30 275.00 n/a n/a n/a
2021-02-10 2020-12-31 13F MESABI TR CTF BEN INT Call 300 -70.00 8 -73.33 n/a n/a n/a
2020-08-13 2020-06-30 13F MESABI TR CTF BEN INT Call 0 -100.00 0 -100.00 n/a n/a n/a
2020-05-13 2020-03-31 13F MESABI TR CTF BEN INT Call 10,200 10,100.00 146 7,200.00 n/a n/a n/a
2020-02-10 2019-12-31 13F MESABI TR CTF BEN INT Call 100 -97.78 2 -98.15 n/a n/a n/a
2019-11-12 2019-09-30 13F MESABI TR CTF BEN INT Call 4,500 -10.00 108 -27.03 n/a n/a n/a
2019-08-09 2019-06-30 13F MESABI TR CTF BEN INT Call 5,000 -60.00 148 -59.56 n/a n/a n/a
2019-05-14 2019-03-31 13F/A MESABI TR CTF BEN INT Call 12,500 -69.44 366 -62.23 n/a n/a n/a
2019-05-13 2019-03-31 13F MESABI TR CTF BEN INT Call 12,500 366 n/a n/a n/a
2019-02-05 2018-12-31 13F MESABI TR CTF BEN INT Call 40,900 227.20 969 164.75 n/a n/a n/a
2018-11-08 2018-09-30 13F MESABI TR CTF BEN INT Call 0 -100.00 0 -100.00 n/a n/a n/a
2018-08-13 2018-06-30 13F MESABI TR CTF BEN INT Call 7,400 -60.85 182 -62.63 n/a n/a n/a
2018-05-16 2018-03-31 13F/A MESABI TR CTF BEN INT Call 18,900 89.00 487 92.49 n/a n/a n/a
2018-05-10 2018-03-31 13F MESABI TR CTF BEN INT Call 18,900 487 n/a n/a n/a
2018-02-09 2017-12-31 13F MESABI TR CTF BEN INT Call 10,000 -47.09 253 -48.05 n/a n/a n/a
2015-05-14 2015-03-31 13F MESABI TR CTF BEN INT Call 0 -100.00 0 -100.00 n/a n/a n/a
2015-02-11 2014-12-31 13F MESABI TR CTF BEN INT Call 1,000 -52.38 17 -57.50 n/a n/a n/a
2014-10-31 2014-09-30 13F MESABI TR CTF BEN INT Call 2,100 600.00 40 566.67 n/a n/a n/a
2014-08-12 2014-06-30 13F MESABI TR CTF BEN INT Call 300 -84.21 6 -85.00 n/a n/a n/a
2014-05-07 2014-03-31 13F MESABI TR CTF BEN INT Call 1,900 -69.84 40 -71.43 n/a n/a n/a
2014-01-31 2013-12-31 13F MESABI TR CTF BEN INT Call 6,300 472.73 140 483.33 n/a n/a n/a
2013-11-15 2013-09-30 13F MESABI TR CTF BEN INT Call 1,100 22.22 24 50.00 n/a n/a n/a
2013-08-02 2013-06-30 13F MESABI TR CTF BEN INT Call 900 16 n/a n/a n/a
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.