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Insider Trading Intelligence
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Michael Martin Breen

GTBP
EXEC. CHAIR. AND INTERIM CEO · GT BIOPHARMA, INC. · CIK 0001863633
FILING MIX · LIFETIME83%/17%
BUYS
10
SELLS
2
TOTAL VALUE
$252.7K
COMPANIES
1
ACTIVE SINCE
Feb 2021
HOLDINGS NOW
100,000
AVG SELL PX
TRADE KIND
SHOWING 12 / 12
Trades · vs SPY
Loading price series…
Performance · forward returns vs SPY
1 backtested trades · 8 horizonsHow are these numbers computed? →
Forward-return performance of every backtestable P/S trade by Michael Martin Breen, measured at 8 horizons from 7 days to 2 years. Deduped per economic event so co-filings count once. Excess return = trade return minus SPY return over the same window.
HORIZONTRADESWIN RATEINSIDER RETURNSPY RETURNMEAN EXCESSMEDIAN EXCESST-STAT
7d1+0.00%-19.73%+1.10%-20.82%-20.82%
14d1+0.00%-32.70%-0.89%-31.82%-31.82%
30d1+0.00%-41.49%+0.59%-42.08%-42.08%
60d1+0.00%-32.70%+4.93%-37.63%-37.63%
90d1+0.00%-46.16%+7.71%-53.87%-53.87%
180d1+0.00%-53.85%+6.27%-60.13%-60.13%
1y1+0.00%-74.36%+27.30%-101.66%-101.66%
2y1+0.00%-85.19%+31.54%-116.74%-116.74%
How to read this: Insider Returnis the average raw return of the filer's trades over the horizon. SPY Return is what SPY did over those same windows — reference only, not a comparison. The headline alpha number is Mean Excess = Insider − SPY; green means the filer beat SPY, red means they trailed it. Win rate is the share of individual trades where the filer beat SPY. T-statvalues above 2 mean the alpha is unlikely to be chance given the sample size. "Pending" counts trades where the horizon hasn't elapsed yet; their stats are not included in the row average.
Holdings over time
GTBP · 100,000 shares · as of Sep 4, 2025
0214,055428,109642,164856,2182022202320242025SHARES HELD
Trading cadence · quarterly flow
BUY SELL
2021
2021
2021
2021
2022
2022
2022
2022
2023
2023
2023
2023
2024
2024
2024
2024
2025
2025
2025
FLOW · 10 buys / 2 sellsCOVERAGE · 19 quarters
Form 4 filings · all activity
COMPANYTYPESHARESPRICEVALUEHELD AFTERTRADE DATEFILEDDETAILS
GTBP
GT BIOPHARMA, INC.
PURCHASEGRANT
Stock grant
100,000100,000Sep 4, 2025Sep 8, 2025View →
GTBP
GT BIOPHARMA, INC.
PURCHASEGRANT
Stock grant
200,000$0.29$57.4K856,218Aug 11, 2023Aug 15, 2023View →
GTBP
GT BIOPHARMA, INC.
PURCHASE
Executive Chairman/Interim CEO
50,000$0.50$25.0K656,218Apr 11, 2023Apr 11, 2023View →
GTBP
GT BIOPHARMA, INC.
PURCHASEGRANT
Stock grant
500,000500,000Jan 27, 2023Jan 31, 2023View →
GTBP
GT BIOPHARMA, INC.
PURCHASEGRANT
Stock grant
50,00050,000Jul 15, 2022Jul 19, 2022View →
GTBP
GT BIOPHARMA, INC.
PURCHASEGRANT
Stock grant
278,058606,218Jul 15, 2022Jul 19, 2022View →
GTBP
GT BIOPHARMA, INC.
SALE
100,0000Feb 25, 2021Nov 9, 2021View →
GTBP
GT BIOPHARMA, INC.
SALE
30,0000Feb 25, 2021Nov 9, 2021View →
GTBP
GT BIOPHARMA, INC.
PURCHASE
9,859$3.40$33.5K328,160Feb 25, 2021Nov 9, 2021View →
GTBP
GT BIOPHARMA, INC.
PURCHASE
40,243$3.40$136.8K318,301Feb 25, 2021Nov 9, 2021View →
GTBP
GT BIOPHARMA, INC.
PURCHASEGRANT
Stock grant
50,00050,000Feb 16, 2021Nov 9, 2021View →
GTBP
GT BIOPHARMA, INC.
PURCHASEGRANT
Stock grant
278,058278,058Feb 16, 2021Nov 9, 2021View →
Other insiders · GTBP
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About this filer
CIK 0001863633
ROLE
Exec. Chair. and Interim CEO
PRIMARY
GTBP
COMPANIES
1
ACTIVE SINCE
Feb 2021
MARKETPEEL · /INSIDER/0001863633DATA · SEC EDGAR · FORM 4 · CONSOLIDATED TAPE
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