글로벌 셀프 스토리지, Inc.
US ˙ NasdaqCM ˙ US37955N1063

SecuritySELF / Global Self Storage, Inc.
InstitutionWinmill & Co. Inc
Latest Disclosed Ownership586,500 shares
Latest Disclosed Value $ 2,997,015
Winmill & Co. Inc ownership in SELF / Global Self Storage, Inc.

On May 14, 2026 - Winmill & Co. Inc filed a 13F-HR form disclosing ownership of 586,500 shares of Global Self Storage, Inc. (US:SELF) valued at $2,997,015 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 13, 2026 disclosing 586,500 shares of Global Self Storage, Inc.. This represents a change in shares of 0.00% during the quarter. The current value of the position is $2,985,285 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 GLOBAL SELF STORAGE COM 37955N106 586,500 0 0.00 2,997 0.20 0.7857
2026-02-13 2025-12-31 13F GLOBAL SELF STORAGE COM 37955N106 586,500 71,907 13.97 2,991 15.57 0.7978
2025-11-13 2025-09-30 13F GLOBAL SELF STORAGE COM 37955N106 514,593 35,551 7.42 2,588 1.17 0.6276
2025-08-01 2025-06-30 13F GLOBAL SELF STORAGE COM 37955N106 479,042 19,280 4.19 2,558 10.40 0.7114
2025-05-14 2025-03-31 13F GLOBAL SELF STORAGE COM 37955N106 459,762 0 0.00 2,317 -5.43 0.7044
2025-02-13 2024-12-31 13F GLOBAL SELF STORAGE COM 37955N106 459,762 0 0.00 2,451 2.30 0.7931
2024-11-14 2024-09-30 13F/A-1 GLOBAL SELF STORAGE COM 37955N106 459,762 20,096 4.57 2,395 12.13 0.8060
2024-11-13 2024-09-30 13F GLOBAL SELF STORAGE COM 37955N106 419,579 -20,087 2,186 0.4201
2024-08-13 2024-06-30 13F GLOBAL SELF STORAGE COM 37955N106 439,666 0 0.00 2,137 9.20 0.7287
2024-05-14 2024-03-31 13F GLOBAL SELF STORAGE COM 37955N106 439,666 0 0.00 1,957 -3.98 0.5569
2024-02-13 2023-12-31 13F GLOBAL SELF STORAGE COM 37955N106 439,666 0 0.00 2,038 -4.63 0.6533
2023-11-13 2023-09-30 13F GLOBAL SELF STORAGE COM 37955N106 439,666 0 0.00 2,137 -3.78 0.7827
2023-08-11 2023-06-30 13F GLOBAL SELF STORAGE COM 37955N106 439,666 0 0.00 2,220 -1.73 0.7942
2023-05-12 2023-03-31 13F GLOBAL SELF STORAGE COM 37955N106 439,666 0 0.00 2,260 5.31 0.8427
2023-02-13 2022-12-31 13F GLOBAL SELF STORAGE COM 37955N106 439,666 0 0.00 2,146 -16.76 0.7812
2022-11-10 2022-09-30 13F GLOBAL SELF STORAGE COM 37955N106 439,666 0 0.00 2,577 4.08 1.0202
2022-08-12 2022-06-30 13F GLOBAL SELF STORAGE COM 37955N106 439,666 0 0.00 2,476 0.57 0.8981
2022-05-13 2022-03-31 13F GLOBAL SELF STORAGE COM 37955N106 439,666 0 0.00 2,462 -1.76 0.7493
2022-02-11 2021-12-31 13F GLOBAL SELF STORAGE COM 37955N106 439,666 0 0.00 2,506 10.69 0.7221
2021-11-12 2021-09-30 13F GLOBAL SELF STORAGE COM 37955N106 439,666 0 0.00 2,264 -1.18 0.7241
2021-08-13 2021-06-30 13F GLOBAL SELF STORAGE COM 37955N106 439,666 0 0.00 2,291 9.46 0.8246
2021-05-14 2021-03-31 13F GLOBAL SELF STORAGE COM 37955N106 439,666 5,087 1.17 2,093 20.08 0.7713
2021-02-12 2020-12-31 13F GLOBAL SELF STORAGE COM 37955N106 434,579 0 0.00 1,743 0.00 0.6849
2020-11-13 2020-09-30 13F GLOBAL SELF STORAGE COM 37955N106 434,579 5,000 1.16 1,743 5.44 0.7143
2020-08-13 2020-06-30 13F GLOBAL SELF STORAGE COM 37955N106 429,579 0 0.00 1,653 9.69 0.6631
2020-04-13 2020-03-31 13F GLOBAL SELF STORAGE COM 37955N106 429,579 0 0.00 1,507 -18.45 0.8197
2020-01-16 2019-12-31 13F GLOBAL SELF STORAGE COM 37955N106 429,579 243,372 130.70 1,848 108.58 0.6321
2019-10-15 2019-09-30 13F GLOBAL SELF STORAGE COM 37955N106 186,207 186,207 886 0.3765
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.