WINMILL MARK CAMPBELL Insider Trading Activity (SELF)

Summary

Updated Jul 16, 2026

WINMILL MARK CAMPBELL has filed 1 SEC Form 4 filing across 1 company in the last 90 days — buying. Lifetime open-market purchases: $162K. Historical track record: 2/5 stars across 5 tracked purchases.

Role	President and CEO, Director
Notability	30/100

Track Record

InsiderAlpha computes a forward-return-based score for every insider with enough Form 4 purchase history. The metrics below reflect realised performance after each tracked open-market purchase.

InsiderAlpha rating	★★☆☆☆ (2/5)
Total purchases tracked	5
Purchases with forward-return data	5
30-day win rate	6000%
90-day win rate	8000%
Avg 5-day return	+65.75%
Avg 30-day return	+25.36%
Avg 90-day return	-37.01%
Best 30-day return	+180.36%

Recent Transactions

Date	Ticker	Company	Code	Shares	Price	Value
2026-05-15	SELF	Global Self Storage, Inc.	P — Open-market purchase	4.0K	$5.33	$21K
2026-03-25	SELF	Global Self Storage, Inc.	A — Grant or award	12.7K	$5.10	$65K
2026-03-25	SELF	Global Self Storage, Inc.	A — Grant or award	12.7K	$5.08	$64K
2025-12-05	SELF	Global Self Storage, Inc.	P — Open-market purchase	3.6K	$5.09	$18K
2025-12-05	SELF	Global Self Storage, Inc.	P — Open-market purchase	800	$5.05	$4K
2025-12-05	SELF	Global Self Storage, Inc.	P — Open-market purchase	6.0K	$5.14	$31K
2025-12-05	SELF	Global Self Storage, Inc.	P — Open-market purchase	6.0K	$5.13	$31K
2025-05-19	SELF	Global Self Storage, Inc.	P — Open-market purchase	10.0K	$5.67	$57K

Frequently Asked Questions

Who is WINMILL MARK CAMPBELL?

WINMILL MARK CAMPBELL is a corporate insider — currently tracked as President and CEO, Director of Global Self Storage, Inc. (SELF). InsiderAlpha tracks every SEC Form 4 filing in real time.

How many SEC Form 4 filings has WINMILL MARK CAMPBELL submitted recently?

1 primary Form 4 filings in the last 90 days, covering 1 company.

Has WINMILL MARK CAMPBELL been buying or selling stock?

Recorded transactions: 6 open-market purchases ($162K) and 0 open-market sales () across all tracked filings.

How accurate is WINMILL MARK CAMPBELL's historical track record?

Across 5 tracked purchases, WINMILL MARK CAMPBELL averaged +25.4% avg 30-day return with a 6000% 30-day win rate. InsiderAlpha rates the track record at 2/5 stars.

Where can I see all of WINMILL MARK CAMPBELL's SEC filings?

All Form 4 filings, transaction values, and 10b5-1 plan flags are listed on this page and updated in real time as new SEC EDGAR filings are processed.

WINMILL MARK CAMPBELL — SEC Form 4 Insider Trading Activity