MarketPeel
Insider Trading Intelligence
BG

Bryan Giraudo

GOSS
COO/CFO · GOSSAMER BIO, INC. · CIK 0001740847
FILING MIX · LIFETIME67%/33%
BUYS
49
SELLS
24
TOTAL VALUE
$6.84M
COMPANIES
2
ACTIVE SINCE
Feb 2020
HOLDINGS NOW
47,667
AVG SELL PX
$74.28
TRADE KIND
SHOWING 73 / 73
Trades · vs SPY
Loading price series…
Performance · forward returns vs SPY
14 backtested trades · 8 horizons · 20 pending
Forward-return performance of every backtestable P/S trade by Bryan Giraudo, 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
7d14+57.14%+11.12%+0.85%+10.27%+4.22%
14d14+41.67%+7.12%+1.40%+6.62%-0.33%
30d14+70.00%+16.34%+2.19%+13.43%+4.76%
60d14(4 pending)+90.00%+15.48%+3.40%+12.09%+14.23%
90d14(4 pending)+90.00%+13.70%+4.60%+9.11%+5.50%
180d14(4 pending)+30.00%-2.33%+10.09%-12.42%-26.51%
1y14(4 pending)+80.00%+2.72%+20.99%-18.27%-18.42%
2y14(4 pending)+60.00%-7.80%+30.46%-38.26%-78.86%
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
GOSS · 47,667 shares · as of Mar 19, 2026
0173,438346,875520,313693,750202120222023202420252026SHARES 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
2025
2025
2025
2026
2026
FLOW · 49 buys / 24 sellsCOVERAGE · 26 quarters
Form 4 filings · all activity
COMPANYTYPESHARESPRICEVALUEHELD AFTERTRADE DATEFILEDDETAILS
PTGX
PROTAGONIST THERAPEUTICS, INC
SALE
5,130$100.00$513.0K12,695May 8, 2026May 11, 2026View →
PTGX
PROTAGONIST THERAPEUTICS, INC
SALE
6,000$100.00$600.0K0May 8, 2026May 11, 2026View →
PTGX
PROTAGONIST THERAPEUTICS, INC
SALE
12,0000May 7, 2026May 11, 2026View →
PTGX
PROTAGONIST THERAPEUTICS, INC
SALE
24,0000May 7, 2026May 11, 2026View →
PTGX
PROTAGONIST THERAPEUTICS, INC
SALE
36,000$100.14$3.61M27,825May 7, 2026May 11, 2026View →
PTGX
PROTAGONIST THERAPEUTICS, INC
SALE
12,000$100.07$1.20M6,000May 7, 2026May 11, 2026View →
PTGX
PROTAGONIST THERAPEUTICS, INC
PURCHASE
12,000$6.98$83.8K43,825May 7, 2026May 11, 2026View →
PTGX
PROTAGONIST THERAPEUTICS, INC
PURCHASE
24,000$6.45$154.8K31,825May 7, 2026May 11, 2026View →
GOSS
GOSSAMER BIO, INC.
SALE
COO/CFO
543,7500Mar 19, 2026Mar 20, 2026View →
GOSS
GOSSAMER BIO, INC.
PURCHASEGRANT
Stock grant
100,000100,000Mar 19, 2026Mar 20, 2026View →
GOSS
GOSSAMER BIO, INC.
PURCHASEGRANT
Stock grant
181,250181,250Mar 19, 2026Mar 20, 2026View →
GOSS
GOSSAMER BIO, INC.
SALE
COO/CFO
693,7500Mar 19, 2026Mar 20, 2026View →
GOSS
GOSSAMER BIO, INC.
SALE
COO/CFO
176,6670Mar 19, 2026Mar 20, 2026View →
GOSS
GOSSAMER BIO, INC.
SALE
COO/CFO
181,2500Mar 19, 2026Mar 20, 2026View →
GOSS
GOSSAMER BIO, INC.
SALE
COO/CFO
211,5000Mar 19, 2026Mar 20, 2026View →
GOSS
GOSSAMER BIO, INC.
PURCHASEGRANT
Stock grant
176,667176,667Mar 19, 2026Mar 20, 2026View →
GOSS
GOSSAMER BIO, INC.
PURCHASEGRANT
Stock grant
543,750543,750Mar 19, 2026Mar 20, 2026View →
GOSS
GOSSAMER BIO, INC.
PURCHASEGRANT
Stock grant
211,500211,500Mar 19, 2026Mar 20, 2026View →
GOSS
GOSSAMER BIO, INC.
SALE
COO/CFO
100,0000Mar 19, 2026Mar 20, 2026View →
GOSS
GOSSAMER BIO, INC.
PURCHASEGRANT
Stock grant
638,000638,000Mar 19, 2026Mar 20, 2026View →
GOSS
GOSSAMER BIO, INC.
PURCHASEGRANT
Stock grant
96,66796,667Mar 19, 2026Mar 20, 2026View →
GOSS
GOSSAMER BIO, INC.
PURCHASEGRANT
Stock grant
693,750693,750Mar 19, 2026Mar 20, 2026View →
GOSS
GOSSAMER BIO, INC.
SALE
COO/CFO
638,0000Mar 19, 2026Mar 20, 2026View →
GOSS
GOSSAMER BIO, INC.
SALE
COO/CFO
96,6670Mar 19, 2026Mar 20, 2026View →
GOSS
GOSSAMER BIO, INC.
SALE
COO/CFO
60,0000Mar 19, 2026Mar 20, 2026View →
GOSS
GOSSAMER BIO, INC.
PURCHASEGRANT
Stock grant
60,00060,000Mar 19, 2026Mar 20, 2026View →
GOSS
GOSSAMER BIO, INC.
SALE
COO/CFO
47,6670Mar 19, 2026Mar 20, 2026View →
GOSS
GOSSAMER BIO, INC.
PURCHASEGRANT
Stock grant
47,66747,667Mar 19, 2026Mar 20, 2026View →
GOSS
GOSSAMER BIO, INC.
PURCHASEGRANT
Stock grant
115,750389,737Jan 2, 2026Jan 5, 2026View →
GOSS
GOSSAMER BIO, INC.
PURCHASEGRANT
Stock grant
693,750693,750Jan 2, 2026Jan 5, 2026View →
PTGX
PROTAGONIST THERAPEUTICS, INC
PURCHASEGRANT
Stock grant
3,7623,762Jan 2, 2026Jan 6, 2026View →
PTGX
PROTAGONIST THERAPEUTICS, INC
PURCHASEGRANT
Stock grant
2,69517,825Jan 2, 2026Jan 6, 2026View →
GOSS
GOSSAMER BIO, INC.
PURCHASEGRANT
Stock grant
181,250273,987Oct 1, 2025Oct 2, 2025View →
GOSS
GOSSAMER BIO, INC.
PURCHASEGRANT
Stock grant
638,000638,000Mar 4, 2025Mar 6, 2025View →
PTGX
PROTAGONIST THERAPEUTICS, INC
PURCHASEGRANT
Stock grant
6,5846,584Jan 2, 2025Jan 6, 2025View →
PTGX
PROTAGONIST THERAPEUTICS, INC
PURCHASEGRANT
Stock grant
5,13015,130Jan 2, 2025Jan 6, 2025View →
GOSS
GOSSAMER BIO, INC.
PURCHASE
COO/CFO
100,000$0.59$59.1K480,010Jun 18, 2024Jun 20, 2024View →
GOSS
GOSSAMER BIO, INC.
SALE
COO/CFO
6,430$1.16$7.4K92,737Mar 27, 2024Mar 28, 2024View →
PTGX
PROTAGONIST THERAPEUTICS, INC
PURCHASEGRANT
Stock grant
25,70025,700Jan 2, 2024Jan 4, 2024View →
GOSS
GOSSAMER BIO, INC.
PURCHASEGRANT
Stock grant
543,750543,750Jan 2, 2024Jan 4, 2024View →
GOSS
GOSSAMER BIO, INC.
PURCHASEGRANT
Stock grant
181,250181,250Nov 20, 2023Nov 22, 2023View →
GOSS
GOSSAMER BIO, INC.
PURCHASE
COO/CFO
200,000$0.56$112.9K380,010Nov 13, 2023Nov 14, 2023View →
GOSS
GOSSAMER BIO, INC.
PURCHASEGRANT
Stock grant
54,020$1.82$98.3K180,010Jul 24, 2023Jul 26, 2023View →
GOSS
GOSSAMER BIO, INC.
PURCHASEGRANT
Stock grant
13,505$0.13$1.7K13,505Jul 24, 2023Jul 26, 2023View →
GOSS
GOSSAMER BIO, INC.
PURCHASEGRANT
Stock grant
60,00060,000May 5, 2023May 9, 2023View →
GOSS
GOSSAMER BIO, INC.
PURCHASEGRANT
Stock grant
100,000100,000May 5, 2023May 9, 2023View →
GOSS
GOSSAMER BIO, INC.
SALE
COO/CFO
150,0000May 5, 2023May 9, 2023View →
GOSS
GOSSAMER BIO, INC.
PURCHASEGRANT
Stock grant
96,66796,667May 5, 2023May 9, 2023View →
GOSS
GOSSAMER BIO, INC.
PURCHASEGRANT
Stock grant
47,66747,667May 5, 2023May 9, 2023View →
GOSS
GOSSAMER BIO, INC.
SALE
COO/CFO
71,5000May 5, 2023May 9, 2023View →
GOSS
GOSSAMER BIO, INC.
SALE
COO/CFO
265,0000May 5, 2023May 9, 2023View →
GOSS
GOSSAMER BIO, INC.
PURCHASEGRANT
Stock grant
176,667176,667May 5, 2023May 9, 2023View →
GOSS
GOSSAMER BIO, INC.
SALE
COO/CFO
90,0000May 5, 2023May 9, 2023View →
GOSS
GOSSAMER BIO, INC.
SALE
COO/CFO
145,0000May 5, 2023May 9, 2023View →
GOSS
GOSSAMER BIO, INC.
PURCHASE
COO/CFO
55,000$1.02$56.1K125,990Apr 4, 2023Apr 5, 2023View →
GOSS
GOSSAMER BIO, INC.
PURCHASE
COO/CFO
50,000$0.97$48.4K70,990Mar 20, 2023Mar 22, 2023View →
GOSS
GOSSAMER BIO, INC.
PURCHASEGRANT
Stock grant
211,500211,500Mar 20, 2023Mar 22, 2023View →
PTGX
PROTAGONIST THERAPEUTICS, INC
PURCHASEGRANT
Stock grant
30,00030,000Jan 16, 2023Jan 18, 2023View →
GOSS
GOSSAMER BIO, INC.
PURCHASEGRANT
Stock grant
211,500211,500Dec 7, 2022Dec 9, 2022View →
GOSS
GOSSAMER BIO, INC.
PURCHASE
COO/CFO
13,869$7.21$100.0K20,990Jul 15, 2022Jul 15, 2022View →
PTGX
PROTAGONIST THERAPEUTICS, INC
PURCHASEGRANT
Stock grant
20,00020,000May 26, 2022May 27, 2022View →
GOSS
GOSSAMER BIO, INC.
SALE
COO/CFO
10,722$8.92$95.6K99,167Mar 23, 2022Mar 24, 2022View →
GOSS
GOSSAMER BIO, INC.
PURCHASEGRANT
Stock grant
265,000265,000Jan 6, 2022Jan 10, 2022View →
GOSS
GOSSAMER BIO, INC.
PURCHASEGRANT
Stock grant
150,000150,000Sep 16, 2021Sep 20, 2021View →
PTGX
PROTAGONIST THERAPEUTICS, INC
PURCHASEGRANT
Stock grant
18,00018,000May 27, 2021May 28, 2021View →
GOSS
GOSSAMER BIO, INC.
SALE
Chief Financial Officer
5,490$9.48$52.0K109,889Mar 23, 2021Mar 25, 2021View →
GOSS
GOSSAMER BIO, INC.
PURCHASEGRANT
Stock grant
45,000115,379Feb 25, 2021Mar 1, 2021View →
GOSS
GOSSAMER BIO, INC.
PURCHASEGRANT
Stock grant
90,00090,000Feb 25, 2021Mar 1, 2021View →
GOSS
GOSSAMER BIO, INC.
PURCHASE
Chief Financial Officer
3,000$10.01$30.0K7,121Oct 14, 2020Oct 14, 2020View →
GOSS
GOSSAMER BIO, INC.
PURCHASE
Chief Financial Officer
2,000$12.96$25.9K4,121Jun 23, 2020Jun 23, 2020View →
PTGX
PROTAGONIST THERAPEUTICS, INC
PURCHASEGRANT
Stock grant
15,00015,000May 28, 2020May 29, 2020View →
GOSS
GOSSAMER BIO, INC.
PURCHASEGRANT
Stock grant
46,50070,379Feb 14, 2020Feb 19, 2020View →
GOSS
GOSSAMER BIO, INC.
PURCHASEGRANT
Stock grant
71,50071,500Feb 14, 2020Feb 19, 2020View →
Other insiders · GOSS
Loading peer insiders…
About this filer
CIK 0001740847
ROLE
COO/CFO
PRIMARY
GOSS
COMPANIES
2
ACTIVE SINCE
Feb 2020
MARKETPEEL · /INSIDER/0001740847DATA · SEC EDGAR · FORM 4 · CONSOLIDATED TAPE
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