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buyModerate cluster of 3

Mark Campbell Winmill bought $57k of SELF

President and CEO at Global Self Storage, Inc.. 10,000 shares at an average of $5.67, traded May 19, 2025, filed May 20, 2025.

Conviction score
47
Value
$57k
10,000 shares
Holdings after
322,838
+3% from before
From 52-week low
+18%
low $4.41, close $5.21
From 52-week high
0%
high $5.21, as of May 19, 2025

Score components

  • Role
    CEO
    +25
  • Trade size
    $57k at market
    +7
  • Relative to holdings
    Holdings up 3.2%
    0
  • Price context
    Mid range
    0
  • Cluster
    3 insiders buying within 14 days
    +15
  • Repeat buying
    First buy in 90 days
    0
  • Track record
    Too few past buys to judge (0 with prices)
    0

What happened after comparable buys

Same side and tier, against the S&P 500, at 1, 3 and 6 months. Shown to Pro users; the whole table is on the backtest page.

This signal so far: 1m -1.0%, 3m -9.2%, 6m -6.8%.

Price around the trade, and since

From a quarter before the trade to today. The arrow is the trade, the circle the day the filing reached EDGAR, which is the first day anyone outside could act; the dotted line is the S&P 500 rebased to that day's close.

SELFOct 9, 2026 · close 4.90
Since filing May 20, 2025: -6.4%SPY +33.4% · excess -39.8%

Daily candles, adjusted for splits and dividends. Green arrows are insider buys, red are sells, sized by value; the dashed line is the close on the filing day, the dotted line SPY rebased to it.Charts by TradingView Lightweight Charts™

Rows in this filing

Every transaction in Form 4 0001031235-25-000009, as filed. Open on EDGAR

DateTransactionSharesPriceValueHoldings afterFiled
May 19, 2025POpen-market purchase
Common Stock
+10,000$5.67$57k322,838May 20, 2025

Related signals

Other insiders at Global Self Storage, Inc. and this insider’s other filings.

ScoreCompanyInsiderValueHoldingsFiled
25Weak
SELFbuy
Global Self Storage, Inc.
Mark Campbell Winmill
President and CEO
$21k
4,000 shares
+1%
28Weak
SELFbuy 2
Global Self Storage, Inc.
Winmill & Co. Inc
other
$86k
15,308 shares
+7%
28Weak
SELFbuy 2
Global Self Storage, Inc.
Winmill & Co. Inc
other
$84k
15,139 shares
+8%
27Weak
SELFbuy 2
Global Self Storage, Inc.
Winmill & Co. Inc
other
$75k
13,778 shares
+7%
27Weak
SELFbuy 2
Global Self Storage, Inc.
Winmill & Co. Inc
other
$68k
12,853 shares
+7%
23Weak
SELFbuy 2
Global Self Storage, Inc.
Russell E Burke III
director
$8,459
1,625 shares
+4%
26Weak
SELFbuy 2
Global Self Storage, Inc.
Winmill & Co. Inc
other
$61k
11,658 shares
+7%
32Weak
SELFbuy 2
Global Self Storage, Inc.
Winmill & Co. Inc
other
$63k
12,135 shares
+8%
25Weak
SELFbuy
Global Self Storage, Inc.
Mark Campbell Winmill
President and CEO
$21k
4,000 shares
+1%
52Moderate
SELFbuy 3
Global Self Storage, Inc.
Mark Campbell Winmill
President and CEO
$84k
16,400 shares
+5%

Not investment advice. Scores and forward returns are decision support built from public SEC filings and past prices; they describe what happened after comparable filings, not what will happen after this one. Do your own research and size your risk.

Mark Campbell Winmill bought $57k of SELF | InsiderTell