Stock Trading Canary

United States · SEC Form 4 · Snapshot date: 2026-10-19 · Built: 2026-10-19 · 中文

← United States · Coverage record

US · SEC FORM 4

RadNet, Inc.

RDNT · Nasdaq · CIK 0000790526 · Healthcare · Diagnostics & Research

INSIDER SIGNAL

No active buy signal

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

10 Form 4 transaction lines observed in the same window
4 sales · 6 option, withholding, award, gift or other lines

Last qualifying purchase2021-08-11 · SWARTZ DAVID L · $151.3K

WHY NO ACTIVE SIGNAL?

Purchase activityNone
Recent buyingNone
Recent salesModerate
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.

Purchase breadth, concentration & cluster buying

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

Insider activity timeline

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

AprMayJunJulAugSepOct
SWARTZ DAVID LDirector
○▼
Berger Howard GPresident, CEO
○○
Wesdorp CornelisPres & CEO, Digital Health
▼
Forthuber Stephen MPres & CEO-Eastern Operations
▼
SPURLOCK GREGORY E.Director
○
Jacobs Laura PastreDirector
○
● Purchase▼ Sale○ Other

Showing the six most active owners; 1 additional owner(s) remain in Form 4 evidence.

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: 2021-08-11 · SWARTZ DAVID L.

Recent Form 4 activity

0Purchases
15Sales
34Other Form 4 lines
30SEC filings · 365 days
BUYING0 qualifying P line(s) · 180 days
SELLING4 sale line(s) · context only
OTHER6 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
9,361,935
Previous report
9,671,100
Avg daily volume
729,300
Days to cover
12.8

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
2021-08-11SWARTZ DAVID LPurchase (P)Common Stock4,519USD 33.47USD 151,251SEC filing ↗
2021-05-14Levitt Lawrence LPurchase (P)Common Stock5,500USD 23.15USD 127,325SEC filing ↗
2021-05-13Levitt Lawrence LPurchase (P)Common Stock7,000USD 23.00USD 161,000SEC filing ↗
2020-03-18Karen B. Kaplan Survivor's TrustPurchase (P)Common Stock10,000USD 5.99USD 59,900SEC filing ↗

Form 4 evidence

49 transaction lines in the latest 365-day window; 296 in local history.

DateOwnerTypeSecuritySharesAvg. priceApprox. valueSource
2026-06-18SWARTZ DAVID LSale (S)Common Stock2,699USD 53.89USD 145,449SEC filing ↗
2026-06-16Wesdorp CornelisSale (S)Common Stock4,750USD 58.11USD 276,022SEC filing ↗
2026-06-16Berger Howard GGift (G)Common Stock90USD 0.00USD 0SEC filing ↗
Show recent Form 4 evidence (30 grouped rows)
DateOwnerTypeSecuritySharesAvg. priceApprox. valueSource
2026-06-18SWARTZ DAVID LSale (S)Common Stock2,699USD 53.89USD 145,449SEC filing ↗
2026-06-16Wesdorp CornelisSale (S)Common Stock4,750USD 58.11USD 276,022SEC filing ↗
2026-06-16Berger Howard GGift (G)Common Stock90USD 0.00USD 0SEC filing ↗
2026-06-15Forthuber Stephen MSale (S)Common Stock44,067USD 58.16USD 2,562,911SEC filing ↗
2026-06-02SWARTZ DAVID LAward / grant (A)Common Stock2,946USD 0.00USD 0SEC filing ↗
2026-06-02SPURLOCK GREGORY E.Award / grant (A)Common Stock2,946USD 0.00USD 0SEC filing ↗
2026-06-02Levitt Lawrence LAward / grant (A)Common Stock2,946USD 0.00USD 0SEC filing ↗
2026-06-02Jacobs Laura PastreAward / grant (A)Common Stock2,946USD 0.00USD 0SEC filing ↗
2026-05-05Berger Howard GOption exercise / conversion (M)Common Stock25,992USD 18.64USD 484,491SEC filing ↗
2026-03-19Sorensen Alma GregorySale (S)Common Stock15,000USD 62.20USD 933,014SEC filing ↗
2026-03-19Sorensen Alma GregoryGift (G)Common Stock7,000USD 0.00USD 0SEC filing ↗
2026-03-18Sorensen Alma GregorySale (S)Common Stock15,000USD 62.15USD 932,280SEC filing ↗
2026-03-16Sorensen Alma GregoryTax withholding (F)Common Stock5,919USD 61.72USD 365,321SEC filing ↗
2026-03-10Sorensen Alma GregoryOption exercise / conversion (M)Common Stock62,964USD 0.00USD 0SEC filing ↗
2026-03-03Wesdorp CornelisAward / grant (A)Common Stock20,330USD 0.00USD 0SEC filing ↗
2026-03-03Sorensen Alma GregoryAward / grant (A)Common Stock16,533USD 0.00USD 0SEC filing ↗
2026-03-03STOLPER MARKAward / grant (A)Common Stock18,228USD 0.00USD 0SEC filing ↗
2026-03-03Patel MitalAward / grant (A)Common Stock20,667USD 0.00USD 0SEC filing ↗
2026-03-03Murdock Michael NAward / grant (A)Common Stock6,613USD 0.00USD 0SEC filing ↗
2026-03-03Katz David JeffreyAward / grant (A)Common Stock19,289USD 0.00USD 0SEC filing ↗
2026-03-03HAMES NORMAN RAward / grant (A)Common Stock25,145USD 0.00USD 0SEC filing ↗
2026-03-03Forthuber Stephen MAward / grant (A)Common Stock22,045USD 0.00USD 0SEC filing ↗
2026-03-03Berger Howard GAward / grant (A)Common Stock124,001USD 0.00USD 0SEC filing ↗
2025-12-10STOLPER MARKOption exercise / conversion (M)Common Stock35,703USD 6.07USD 216,717SEC filing ↗
2025-12-10Katz David JeffreyOption exercise / conversion (M)Common Stock3,396USD 29.44USD 99,978SEC filing ↗
2025-12-05Forthuber Stephen MSale (S)Common Stock45,088USD 78.33USD 3,531,849SEC filing ↗
2025-12-03Patel MitalGift (G)Common Stock630USD 0.00USD 0SEC filing ↗
2025-12-03Forthuber Stephen MOption exercise / conversion (M)Common Stock39,127USD 6.07USD 237,501SEC filing ↗
2025-11-25Levitt Lawrence LGift (G)Common Stock2,700USD 0.00USD 0SEC filing ↗
2025-11-19Berger Howard GOption exercise / conversion (M)Common Stock129,961USD 18.64USD 2,422,473SEC 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 date2026-10-19
Ranking versionUS-v1.2
Data qualityPASS ELIGIBLE · —
TickerRDNT
CIK0000790526
SectorHealthcare
IndustryDiagnostics & Research Yahoo Finance
SEC SIC8071 Services-Medical Laboratories
ExchangeNasdaq

Data coverage

Local Form 4 history296 transaction lines from 2020-01-06 to 2026-06-18
4 P purchase lines · 127 S sale lines · 165 other lines
SEC company submissionsOpen SEC filings ↗

Local ledger as of 2026-10-19. Mapping status is an audit field and does not erase SEC filing evidence.