MarketPeel
Insider Trading Intelligence
AG

Andrew J. Grethlein

GERN
EVP, CHIEF OPERATING OFFICER · GERON CORP · CIK 0001270921
FILING MIX · LIFETIME62%/38%
BUYS
13
SELLS
8
TOTAL VALUE
$6.02M
COMPANIES
1
ACTIVE SINCE
Feb 2020
HOLDINGS NOW
140,000
AVG SELL PX
$4.00
TRADE KIND
SHOWING 21 / 21
Trades · vs SPY
Loading price series…
Performance · forward returns vs SPY
3 backtested trades · 8 horizons · 1 pendingHow are these numbers computed? →
Forward-return performance of every backtestable P/S trade by Andrew J. Grethlein, 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
7d3+66.67%-3.70%+0.57%-4.27%-9.93%
14d3+66.67%-3.99%-1.09%-2.90%-6.06%
30d3+66.67%-9.53%-5.67%-3.86%-9.41%
60d3+100.00%-23.99%-0.23%-23.76%-33.89%
90d3+100.00%-7.00%+2.06%-9.06%-8.12%
180d3+100.00%-8.17%+9.81%-17.98%-12.73%
1y3+100.00%-43.04%+20.92%-63.96%-54.89%
2y3(1 pending)+100.00%-2.66%+51.74%-54.40%-54.40%
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
GERN · 140,000 shares · as of Feb 18, 2025
0300,000600,000900,0001,200,00020212022202320242025SHARES HELD
Trading cadence · quarterly flow
BUY SELL
2020
2020
2020
2020
2021
2021
2021
2021
2022
2022
2022
2022
2023
2023
2023
2023
2024
2024
2024
2024
2025
FLOW · 13 buys / 8 sellsCOVERAGE · 21 quarters
Form 4 filings · all activity
COMPANYTYPESHARESPRICEVALUEHELD AFTERTRADE DATEFILEDDETAILS
GERN
GERON CORP
PURCHASEGRANT
Stock grant
839,000839,000Feb 18, 2025Feb 20, 2025View →
GERN
GERON CORP
PURCHASEGRANT
Stock grant
140,000140,000Feb 18, 2025Feb 20, 2025View →
GERN
GERON CORP
SALE
EVP, Chief Operating Officer
221,5440Jul 8, 2024Jul 10, 2024View →
GERN
GERON CORP
SALE
EVP, Chief Operating Officer
452,8040Jul 8, 2024Jul 10, 2024View →
GERN
GERON CORP
PURCHASE
EVP, Chief Operating Officer
674,348$1.72$1.16M674,348Jul 8, 2024Jul 10, 2024View →
GERN
GERON CORP
SALE
EVP, Chief Operating Officer
674,348$4.56$3.07M0Jul 8, 2024Jul 10, 2024View →
GERN
GERON CORP
PURCHASEGRANT
Stock grant
452,804452,804Jun 6, 2024Jun 7, 2024View →
GERN
GERON CORP
PURCHASEGRANT
Stock grant
1,200,0001,200,000Feb 14, 2024Feb 16, 2024View →
GERN
GERON CORP
PURCHASEGRANT
Stock grant
221,544221,544Aug 15, 2023Sep 21, 2023View →
GERN
GERON CORP
PURCHASEGRANT
Stock grant
780,000780,000Feb 22, 2023Feb 24, 2023View →
GERN
GERON CORP
SALE
EVP, Chief Operating Officer
234,719$3.03$711.2K0Feb 9, 2023Feb 10, 2023View →
GERN
GERON CORP
SALE
EVP, Chief Operating Officer
150,000$3.03$454.5K234,719Feb 9, 2023Feb 10, 2023View →
GERN
GERON CORP
SALE
EVP, Chief Operating Officer
150,0000Feb 9, 2023Feb 10, 2023View →
GERN
GERON CORP
PURCHASE
EVP, Chief Operating Officer
150,000$1.51$226.5K384,719Feb 9, 2023Feb 10, 2023View →
GERN
GERON CORP
PURCHASE
EVP, Chief Operating Officer
232,719$1.70$395.6K234,719Sep 12, 2022Sep 14, 2022View →
GERN
GERON CORP
PURCHASE
EVP, Chief Operating Officer
2,000$1.70$3.4K2,000Sep 12, 2022Sep 14, 2022View →
GERN
GERON CORP
SALE
EVP, Chief Operating Officer
232,7190Sep 12, 2022Sep 14, 2022View →
GERN
GERON CORP
SALE
EVP, Chief Operating Officer
2,00065,281Sep 12, 2022Sep 14, 2022View →
GERN
GERON CORP
PURCHASEGRANT
Stock grant
750,000750,000Feb 16, 2022Feb 18, 2022View →
GERN
GERON CORP
PURCHASEGRANT
Stock grant
300,000300,000Feb 2, 2021Feb 4, 2021View →
GERN
GERON CORP
PURCHASEGRANT
Stock grant
291,375291,375Feb 12, 2020Feb 14, 2020View →
Other insiders · GERN
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About this filer
CIK 0001270921
ROLE
EVP, Chief Operating Officer
PRIMARY
GERN
COMPANIES
1
ACTIVE SINCE
Feb 2020
MARKETPEEL · /INSIDER/0001270921DATA · SEC EDGAR · FORM 4 · CONSOLIDATED TAPE
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