Stock Trading Canary

United States · SEC Form 4 · Snapshot date: 2026-10-18 · Built: 2026-10-18 · 中文

← United States · Coverage record

US · SEC FORM 4

SUTRO BIOPHARMA, INC.

STRO · Nasdaq · CIK 0001382101 · Healthcare · Biotechnology

INSIDER SIGNAL

No active buy signal

0 qualifying P purchase groups
in the current 180-day scoring window

3 Form 4 transaction lines observed in the same window
0 sales · 3 option, withholding, award, gift or other lines

Last qualifying purchase2025-10-15 · Gerber Hans-Peter · $13.6K

WHY NO ACTIVE SIGNAL?

Purchase activityNone
Recent buyingNone
Recent salesNone
Buy signal statusInactive
Score anatomy

No score is calculated because there is no qualifying purchase in the active window. Unavailable inputs are not treated as zero or as a bearish signal.

ClusterNot calculated
Purchase sizeNot calculated
RoleNot calculated
RecencyNot calculated
ConvictionNot calculated

Why is there no score?

  • No qualifying open-market purchase supplies cluster, size, role, recency or conviction inputs.
  • Sales and other Form 4 activity remain visible as context and do not create a negative score.

Sales and other Form 4 activity are shown separately and do not create a negative buy signal. Absence of buying is not scored as bearish.

Insider activity timeline

Owner lanes show the latest 180 days. Symbol shape identifies the transaction type; sales remain context only.

AprMayJunJulAugSepOct
Gerber Hans-PeterCHIEF SCIENTIFIC OFFICER
○○
Chow Gregory K.CFO
○
● Purchase▼ Sale○ Other

—

Purchase breadth, concentration & cluster buying

These modules activate when qualifying purchases enter the 180-day research window.

SIGNAL HISTORY

No recorded active-signal snapshot

Scores are archived only when the company qualifies for a published US buy-signal snapshot. Last qualifying purchase: 2025-10-15 · Gerber Hans-Peter.

Recent Form 4 activity

0Purchases
0Sales
23Other Form 4 lines
8SEC filings · 365 days
BUYING0 qualifying P line(s) · 180 days
SELLING0 sale line(s) · context only
OTHER3 exercise / withholding / award / gift / other lines
10b5-1 / PLANNEDNot assessed

P is an open-market or private purchase. S is a sale. M, F, A and G usually describe exercises, tax withholding, awards and gifts. These categories remain visually separate.

Market context

Market context has not been captured for this ticker yet. The daily market-context job processes the US universe in rotating batches.

Short interest

Short interest is external context reported to FINRA by broker-dealers. It does not affect the Insider Signal.

Shares short
1,847,453
Previous report
2,076,152
Avg daily volume
285,322
Days to cover
6.5

FINRA settlement date: 2026-09-30 · Captured 2026-10-12 · FINRA equity short interest ↗. A share count, published about a week after each of two settlement dates a month; not a percentage of shares outstanding.

Historical equity purchases

Qualifying code P transactions in the local Form 4 history, including purchases outside the current signal window.

Transaction dateReporting ownerTypeSecuritySharesAvg. priceApprox. valueSource
2025-10-15Pauling DavidPurchase (P)Common Stock12,504USD 0.80USD 10,003SEC filing ↗
2025-10-15MATSUI CONNIEPurchase (P)Common Stock50,000USD 0.80USD 40,000SEC filing ↗
2025-10-15Gerber Hans-PeterPurchase (P)Common Stock17,000USD 0.80USD 13,600SEC filing ↗
2025-10-15Chung JanePurchase (P)Common Stock12,500USD 0.80USD 10,000SEC filing ↗
2025-10-15Chow Gregory K.Purchase (P)Common Stock19,750USD 0.81USD 15,998SEC filing ↗
2022-03-14NEWELL WILLIAM JPurchase (P)Common Stock10,000USD 7.75USD 77,500SEC filing ↗
2020-05-14NEWELL WILLIAM JPurchase (P)Common Stock64,516USD 7.75USD 499,999SEC filing ↗
2020-05-14MOLINA ARTURO MDPurchase (P)Common Stock6,451USD 7.75USD 49,995SEC filing ↗
2020-05-14FITZPATRICK LINDA APurchase (P)Common Stock3,225USD 7.75USD 24,994SEC filing ↗

Form 4 evidence

23 transaction lines in the latest 365-day window; 293 in local history.

DateOwnerTypeSecuritySharesAvg. priceApprox. valueSource
2026-09-18Gerber Hans-PeterOption exercise / conversion (M)Common Stock3,750USD 0.00USD 0SEC filing ↗
2026-09-18Gerber Hans-PeterTax withholding (F)Common Stock1,345USD 15.34USD 20,632SEC filing ↗
2026-06-02Chow Gregory K.Option exercise / conversion (M)Common Stock2,500USD 0.00USD 0SEC filing ↗
Show recent Form 4 evidence (21 grouped rows)
DateOwnerTypeSecuritySharesAvg. priceApprox. valueSource
2026-09-18Gerber Hans-PeterOption exercise / conversion (M)Common Stock3,750USD 0.00USD 0SEC filing ↗
2026-09-18Gerber Hans-PeterTax withholding (F)Common Stock1,345USD 15.34USD 20,632SEC filing ↗
2026-06-02Chow Gregory K.Option exercise / conversion (M)Common Stock2,500USD 0.00USD 0SEC filing ↗
2026-03-04Pauling DavidOption exercise / conversion (M)Common Stock675USD 0.00USD 0SEC filing ↗
2026-03-04Pauling DavidTax withholding (F)Common Stock277USD 21.31USD 5,903SEC filing ↗
2026-03-04Chung JaneOption exercise / conversion (M)Common Stock788USD 0.00USD 0SEC filing ↗
2026-03-04Chung JaneTax withholding (F)Common Stock282USD 21.31USD 6,009SEC filing ↗
2026-03-02Pauling DavidOption exercise / conversion (M)Common Stock2,356USD 0.00USD 0SEC filing ↗
2026-03-02Pauling DavidTax withholding (F)Common Stock970USD 20.55USD 19,934SEC filing ↗
2026-03-02Gerber Hans-PeterOption exercise / conversion (M)Common Stock2,843USD 0.00USD 0SEC filing ↗
2026-03-02Gerber Hans-PeterTax withholding (F)Common Stock1,170USD 20.55USD 24,044SEC filing ↗
2026-03-02Chung JaneOption exercise / conversion (M)Common Stock7,750USD 0.00USD 0SEC filing ↗
2026-03-02Chung JaneTax withholding (F)Common Stock2,779USD 20.55USD 57,108SEC filing ↗
2026-03-01Pauling DavidOption exercise / conversion (M)Common Stock1,342USD 0.00USD 0SEC filing ↗
2026-03-01Pauling DavidTax withholding (F)Common Stock551USD 20.47USD 11,279SEC filing ↗
2026-03-01Gerber Hans-PeterOption exercise / conversion (M)Common Stock1,125USD 0.00USD 0SEC filing ↗
2026-03-01Gerber Hans-PeterTax withholding (F)Common Stock463USD 20.47USD 9,478SEC filing ↗
2026-03-01Chung JaneOption exercise / conversion (M)Common Stock3,188USD 0.00USD 0SEC filing ↗
2026-03-01Chung JaneTax withholding (F)Common Stock1,271USD 20.47USD 26,017SEC filing ↗
2025-12-12Chung JaneOption exercise / conversion (M)Common Stock2,500USD 0.00USD 0SEC filing ↗
2025-12-12Chung JaneTax withholding (F)Common Stock894USD 8.02USD 7,170SEC filing ↗

Multiple price lines in one filing are grouped and share-weighted. Price and value are blank when a grouped filing line lacks price evidence.

Snapshot & identity

Snapshot date2026-10-18
Ranking versionUS-v1.2
Data qualityPASS ELIGIBLE · —
TickerSTRO
CIK0001382101
SectorHealthcare
IndustryBiotechnology Yahoo Finance
SEC SIC2836 Biological Products, (No Diagnostic Substances)
ExchangeNasdaq

Data coverage

Local Form 4 history293 transaction lines from 2020-01-27 to 2026-09-18
9 P purchase lines · 22 S sale lines · 262 other lines
SEC company submissionsOpen SEC filings ↗

Local ledger as of 2026-10-18. Mapping status is an audit field and does not erase SEC filing evidence.