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

Fulcrum Therapeutics, Inc.

FULC · Nasdaq · CIK 0001680581 · Healthcare · Biotechnology

INSIDER SIGNAL

51.6 / 100

1 buyers · 6 purchase transaction lines · $1.5M gross purchase

WHY THIS SIGNAL?

Buyer breadthLow
Purchase sizeModerate
RoleModerate
RecencyLow
ConvictionStrong
Score anatomy

Each bar shows the contribution to the current score; the weights and formula stay unchanged.

Cluster+7.0 / 35
Purchase size+18.9 / 25
Role+14.0 / 20
Recency+2.1 / 10
Conviction+9.6 / 10

What is holding the score back?

  • ⚠ Cluster breadth is moderate · 1 insider(s), not 4+
  • ⚠ Role scores low · most senior buyer: TenPercentOwner (CEO, chair and 10% owners score lowest)
  • ⚠ Purchase activity is becoming less recent

Purchase-size comments are relative to the model scale. Average daily volume is a separate market-context diagnostic.

US-v1.2 ranks qualifying equity purchases under the current 180-day rules. The score is a research priority, not a return forecast or probability. Backtests have not shown that a higher US score is followed by better returns.

Insider activity timeline

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

AprMayJunJulAugSepOct
TANG CAPITAL MANAGEMENT LLC; TANG KEVINTenPercentOwner
●●●●●
Ezekowitz AlanDirector
▼
● Purchase▼ Sale○ Other

—

Purchase breadth & concentration

QUALIFYING BUYERS1
PURCHASE CONCENTRATION100%Largest buyer: TANG CAPITAL MANAGEMENT LLC; TANG KEVIN · $1.5M
CLUSTER BUYING · 15D1 insiderPeak activity: 2026-07-13–2026-07-17

Roles in the peak window: TenPercentOwner. Concentration uses priced qualifying P lines only and does not change the saved score.

SIGNAL HISTORY

51.6 / 100

Latest recorded score

↓ -0.1 ptsversus the previous recorded snapshot
  1. 51.9
  2. 51.9
  3. 51.8
  4. 51.7
  5. 51.6

Only scores saved when a full US scoring run completed are shown; gaps are not reconstructed.

Recent Form 4 activity

6Purchases
9Sales
0Other Form 4 lines
9SEC filings · 365 days
BUYING6 qualifying P line(s) · 180 days
SELLING1 sale line(s) · context only
OTHER0 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 provides additional background on recent price performance and risk. It does not affect the Insider Signal.

Price performance

1M
-0.8%
3M
+6.5%
6M
-50.1%
12M
-60.9%

Volatility & liquidity

Volatility
85.6%
Beta
—
Avg daily value
USD 5.8M

Valuation

Market cap
USD 287.6M
P/E
—

Fundamentals

Profit margin
—
ROE
-21.5%
Industry
Biotechnology

Market data

Price data up to: 2026-10-11 · Price source: OpenBB/yfinance; volume from price cache (yfinance) · From SEC filings: Market cap, ROE · Fiscal year ended: 2025-12-31 · Market cap is the shares outstanding stated on the filing cover multiplied by the latest close. Share count date: 2026-07-23 · Status: PASS

Short interest

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

Shares short
7,110,810
Previous report
7,194,912
Avg daily volume
1,587,423
Days to cover
4.5

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
2026-07-17TANG CAPITAL MANAGEMENT LLC; TANG KEVINPurchase (P)Common Stock50,945USD 3.52USD 179,326SEC filing ↗
2026-07-16TANG CAPITAL MANAGEMENT LLC; TANG KEVINPurchase (P)Common Stock116,671USD 3.56USD 415,349SEC filing ↗
2026-07-15TANG CAPITAL MANAGEMENT LLC; TANG KEVINPurchase (P)Common Stock107,377USD 3.56USD 382,262SEC filing ↗
2026-07-14TANG CAPITAL MANAGEMENT LLC; TANG KEVINPurchase (P)Common Stock129,603USD 3.57USD 462,906SEC filing ↗
2026-07-13TANG CAPITAL MANAGEMENT LLC; TANG KEVINPurchase (P)Common Stock12,966USD 3.54USD 45,900SEC filing ↗
2024-03-04Sapir AlexPurchase (P)Common Stock43,360USD 11.35USD 492,136SEC filing ↗
2023-01-20Kolchinsky Peter; RA CAPITAL MANAGEMENT, L.P.; RA Capital Healthcare Fund LP; Shah Rajeev M.Purchase (P)Common Stock1,923,076USD 13.00USD 24,999,988SEC filing ↗
2023-01-04Kolchinsky Peter; RA CAPITAL MANAGEMENT, L.P.; RA Capital Healthcare Fund LP; Shah Rajeev M.Purchase (P)Common Stock180,703USD 7.28USD 1,315,286SEC filing ↗
2022-12-27Kolchinsky Peter; RA CAPITAL MANAGEMENT, L.P.; RA Capital Healthcare Fund LP; Shah Rajeev M.Purchase (P)Common Stock4,089USD 5.99USD 24,493SEC filing ↗
2022-12-19Kolchinsky Peter; RA CAPITAL MANAGEMENT, L.P.; RA Capital Healthcare Fund LP; Shah Rajeev M.Purchase (P)Common Stock98,787USD 5.90USD 582,843SEC filing ↗
2022-12-16Kolchinsky Peter; RA CAPITAL MANAGEMENT, L.P.; RA Capital Healthcare Fund LP; Shah Rajeev M.Purchase (P)Common Stock1,341,420USD 5.42USD 7,270,496SEC filing ↗
2022-12-15Kolchinsky Peter; RA CAPITAL MANAGEMENT, L.P.; RA Capital Healthcare Fund LP; Shah Rajeev M.Purchase (P)Common Stock237,029USD 5.50USD 1,303,660SEC filing ↗
2022-12-14Kolchinsky Peter; RA CAPITAL MANAGEMENT, L.P.; RA Capital Healthcare Fund LP; Shah Rajeev M.Purchase (P)Common Stock824,600USD 5.46USD 4,502,316SEC filing ↗
2021-06-28Thomson Peter G.Purchase (P)Common Stock2,300USD 9.00USD 20,700SEC filing ↗
2021-06-28Oltmans Curtis GalePurchase (P)Common Stock1,088USD 9.01USD 9,803SEC filing ↗

Form 4 evidence

15 transaction lines in the latest 365-day window; 127 in local history.

DateOwnerTypeSecuritySharesAvg. priceApprox. valueSource
2026-07-17TANG CAPITAL MANAGEMENT LLC; TANG KEVINPurchase (P)Common Stock50,945USD 3.52USD 179,326SEC filing ↗
2026-07-16TANG CAPITAL MANAGEMENT LLC; TANG KEVINPurchase (P)Common Stock116,671USD 3.56USD 415,349SEC filing ↗
2026-07-15TANG CAPITAL MANAGEMENT LLC; TANG KEVINPurchase (P)Common Stock107,377USD 3.56USD 382,262SEC filing ↗
Show recent Form 4 evidence (12 grouped rows)
DateOwnerTypeSecuritySharesAvg. priceApprox. valueSource
2026-07-17TANG CAPITAL MANAGEMENT LLC; TANG KEVINPurchase (P)Common Stock50,945USD 3.52USD 179,326SEC filing ↗
2026-07-16TANG CAPITAL MANAGEMENT LLC; TANG KEVINPurchase (P)Common Stock116,671USD 3.56USD 415,349SEC filing ↗
2026-07-15TANG CAPITAL MANAGEMENT LLC; TANG KEVINPurchase (P)Common Stock107,377USD 3.56USD 382,262SEC filing ↗
2026-07-14TANG CAPITAL MANAGEMENT LLC; TANG KEVINPurchase (P)Common Stock129,603USD 3.57USD 462,906SEC filing ↗
2026-07-13TANG CAPITAL MANAGEMENT LLC; TANG KEVINPurchase (P)Common Stock12,966USD 3.54USD 45,900SEC filing ↗
2026-06-26Ezekowitz AlanSale (S)Common Stock18,000USD 3.65USD 65,700SEC filing ↗
2026-02-02Gould Robert JSale (S)Common Stock15,000USD 10.72USD 160,800SEC filing ↗
2026-01-02Gould Robert JSale (S)Common Stock15,000USD 10.87USD 163,050SEC filing ↗
2026-01-02Gould Robert JSale (S)Common Stock15,000USD 11.87USD 178,050SEC filing ↗
2025-12-15Oltmans Curtis GaleSale (S)Common Stock3,452USD 12.92USD 44,600SEC filing ↗
2025-12-08Kolchinsky Peter; RA CAPITAL MANAGEMENT, L.P.; RA Capital Healthcare Fund LP; Shah Rajeev M.Sale (S)Common Stock4,175,139USD 13.98USD 58,377,021SEC filing ↗
2025-11-19Gould Robert JSale (S)Common Stock15,000USD 11.03USD 165,450SEC 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 · —
TickerFULC
CIK0001680581
SectorHealthcare
IndustryBiotechnology Yahoo Finance
SEC SIC2834 Pharmaceutical Preparations
ExchangeNasdaq

Data coverage

Local Form 4 history127 transaction lines from 2020-01-23 to 2026-07-17
19 P purchase lines · 70 S sale lines · 38 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.