Mesabi Trust
US ˙ NYSE ˙ US5906721015

SecurityMSB / Mesabi Trust
InstitutionUBS Group AG
Latest Disclosed Ownership20,304 shares
Latest Disclosed Value $ 639,577
UBS Group AG ownership in MSB / Mesabi Trust

On May 5, 2026 - UBS Group AG filed a 13F-HR form disclosing ownership of 20,304 shares of Mesabi Trust (US:MSB) valued at $639,576 USD as of March 31, 2026. The entity filed a previous 13F-HR on January 29, 2026 disclosing 22,739 shares of Mesabi Trust. This represents a change in shares of -10.71% during the quarter. The current value of the position is $518,158 USD.

UBS Group AG has a history of taking positions in derivatives of the underlying security (MSB) in the form of stock options.

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)
2026-05-05 2026-03-31 13F MESABI TR CTF BEN INT 590672101 20,304 -2,435 -10.71 640 -26.97 0.0000
2026-01-29 2025-12-31 13F MESABI TR CTF BEN INT 590672101 22,739 7,350 47.76 876 94.44 0.0000
2025-11-13 2025-09-30 13F MESABI TR CTF BEN INT 590672101 15,389 -14,417 -48.37 450 -36.97 0.0001
2025-08-14 2025-06-30 13F MESABI TR CTF BEN INT 590672101 29,806 -7,905 -20.96 714 -30.34 0.0001
2025-05-13 2025-03-31 13F MESABI TR CTF BEN INT 590672101 37,711 12,598 50.17 1,026 45.39 0.0002
2025-02-14 2024-12-31 13F MESABI TR CTF BEN INT 590672101 25,113 14,644 139.88 706 197.47 0.0001
2024-11-14 2024-09-30 13F MESABI TR CTF BEN INT 590672101 10,469 7,950 315.60 237 451.16 0.0001
2024-08-14 2024-06-30 13F MESABI TR CTF BEN INT 590672101 2,519 -1,166 -31.64 43 -33.85 0.0000
2024-05-13 2024-03-31 13F MESABI TR CTF BEN INT 590672101 3,685 -2,300 -38.43 65 -46.72 0.0000
2024-02-09 2023-12-31 13F MESABI TR CTF BEN INT 590672101 5,985 -169 -2.75 123 -0.81 0.0000
2023-11-09 2023-09-30 13F MESABI TR CTF BEN INT 590672101 6,154 -516 -7.74 124 -9.56 0.0000
2023-08-11 2023-06-30 13F MESABI TR CTF BEN INT 590672101 6,670 2,972 80.37 136 46.24 0.0000
2023-05-12 2023-03-31 13F MESABI TR CTF BEN INT 590672101 3,698 -3,040 -45.12 93 -23.14 0.0000
2023-02-08 2022-12-31 13F MESABI TR CTF BEN INT 590672101 6,738 -6,816 -50.29 121 -58.42 0.0000
2022-11-10 2022-09-30 13F MESABI TR CTF BEN INT 590672101 13,554 607 4.69 291 -8.20 0.0001
2022-08-10 2022-06-30 13F MESABI TR CTF BEN INT 590672101 12,947 261 2.06 317 -6.21 0.0001
2022-05-16 2022-03-31 13F MESABI TR CTF BEN INT 590672101 12,686 7,145 128.95 338 131.51 0.0001
2022-02-14 2021-12-31 13F MESABI TR CTF BEN INT 590672101 5,541 3,483 169.24 146 139.34 0.0000
2021-11-15 2021-09-30 13F MESABI TR CTF BEN INT 590672101 2,058 -1,799 -46.64 61 -55.47 0.0000
2021-08-13 2021-06-30 13F MESABI TR CTF BEN INT 590672101 3,857 532 16.00 137 37.00 0.0000
2021-05-12 2021-03-31 13F MESABI TR CTF BEN INT 590672101 3,325 -1,928 -36.70 100 -31.97 0.0000
2021-02-11 2020-12-31 13F MESABI TR CTF BEN INT 590672101 5,253 -1,210 -18.72 147 7.30 0.0000
2020-11-12 2020-09-30 13F MESABI TR CTF BEN INT 590672101 6,463 1,424 28.26 137 55.68 0.0001
2020-07-31 2020-06-30 13F MESABI TR CTF BEN INT 590672101 5,039 0 0.00 88 22.22 0.0000
2020-05-01 2020-03-31 13F MESABI TR CTF BEN INT 590672101 5,039 -390 -7.18 72 -43.75 0.0000
2020-02-14 2019-12-31 13F MESABI TR CTF BEN INT 590672101 5,429 390 7.74 128 5.79 0.0000
2019-11-14 2019-09-30 13F MESABI TR CTF BEN INT 590672101 5,039 0 0.00 121 -18.79 0.0000
2019-08-14 2019-06-30 13F MESABI TR CTF BEN INT 590672101 5,039 0 0.00 149 0.68 0.0001
2019-05-14 2019-03-31 13F MESABI TR CTF BEN INT 590672101 5,039 -1,425 -22.05 148 -3.27 0.0001
2019-02-14 2018-12-31 13F MESABI TR CTF BEN INT 590672101 6,464 1,925 42.41 153 27.50 0.0001
2018-11-14 2018-09-30 13F MESABI TR CTF BEN INT 590672101 4,539 0 0.00 120 8.11 0.0000
2018-08-14 2018-06-30 13F MESABI TR CTF BEN INT 590672101 4,539 3,839 548.43 111 516.67 0.0000
2018-05-15 2018-03-31 13F MESABI TR CTF BEN INT 590672101 700 -413 -37.11 18 -35.71 0.0000
2018-02-14 2017-12-31 13F MESABI TR CTF BEN INT 590672101 1,113 -5,224 -82.44 28 -80.82 0.0000
2017-11-14 2017-09-30 13F MESABI TR CTF BEN INT 590672101 6,337 2,395 60.76 146 170.37 0.0001
2017-11-14 2017-06-30 13F/A-1 MESABI TR CTF BEN INT 590672101 3,942 3,542 885.50 54 800.00 0.0000
2017-08-14 2017-06-30 13F MESABI TR CTF BEN INT 590672101 3,942 3,542 54
2017-11-14 2017-03-31 13F/A-1 MESABI TR CTF BEN INT 590672101 400 -2,292 -85.14 6 -79.31 0.0000
2017-05-12 2017-03-31 13F MESABI TR CTF BEN INT 590672101 400 -2,292 6
2017-02-14 2016-12-31 13F MESABI TR CTF BEN INT 590672101 2,692 -469 -14.84 29 0.00 0.0000
2016-11-14 2016-09-30 13F MESABI TR CTF BEN INT 590672101 3,161 0 0.00 29 -14.71 0.0000
2016-08-12 2016-06-30 13F MESABI TR CTF BEN INT 590672101 3,161 -539 -14.57 34 54.55 0.0000
2016-05-12 2016-03-31 13F MESABI TR CTF BEN INT 590672101 3,700 -109 -2.86 22 29.41 0.0000
2016-02-16 2015-12-31 13F MESABI TR CTF BEN INT 590672101 3,809 -204 -5.08 17 -65.31 0.0000
2015-11-13 2015-09-30 13F MESABI TR CTF BEN INT 590672101 4,013 2,680 201.05 49 172.22 0.0000
2015-08-14 2015-06-30 13F MESABI TR CTF BEN INT 590672101 1,333 137 11.45 18 12.50 0.0000
2015-05-14 2015-03-31 13F MESABI TR CTF BEN INT 590672101 1,196 196 19.60 16 -5.88 0.0000
2015-02-17 2014-12-31 13F MESABI TR CTF BEN INT 590672101 1,000 1,000 17 0.0000
Disclosed Put 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
(%)
2015-08-14 2015-06-30 13F MESABI TR CTF BEN INT Put 0 -100.00 0 -100.00 n/a n/a n/a
2015-05-14 2015-03-31 13F MESABI TR CTF BEN INT Put 100 -75.00 1 -85.71 n/a n/a n/a
2015-02-17 2014-12-31 13F MESABI TR CTF BEN INT Put 400 7 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.