ONeil Mark F

SEC Form 4 insider trading activity

ONeil Mark F has filed 3 SEC Form 4 filings (4 transaction rows) across 1 company, with disclosures dating back to 2025. 3 of those filings fall inside the rolling window. Most recent filing: Jun 29, 2026.

On the most recent filing, ONeil Mark F is listed as Director at CARMAX INC. Inside the rolling window, ONeil Mark F reported 2 open-market purchases totaling $751K in KMX and no open-market sales. The largest disclosed transaction in the window is a purchase of 10,816 KMX shares on Oct 2, 2025, worth $500K.

Companies traded

Other insiders at KMX

Insider Buying

$751K

reported purchases (SEC code P)

Insider Selling

$0

reported sales (SEC code S)

Companies

1

in the rolling window

Source
KMXPurchase$251KJun 26SEC ↗
KMXPurchase$500KOct 6SEC ↗
Showing 1–2 of 2
1 / 1

Frequently asked questions

How many SEC Form 4 filings has ONeil Mark F made?

ONeil Mark F has filed 3 SEC Form 4 filings (4 transaction rows) across 1 company since 2025.

Which companies does ONeil Mark F trade?

ONeil Mark F has filed SEC Form 4 disclosures for 1 company, including KMX.

When was ONeil Mark F's most recent SEC Form 4 filing?

ONeil Mark F's most recent SEC Form 4 filing on Tracefour is dated Jun 29, 2026.

What is ONeil Mark F's total buy and sell value in the current window?

Inside the rolling retention window, ONeil Mark F bought $751K and sold $0 based on SEC Form 4 filings.

What was ONeil Mark F's largest disclosed transaction?

The largest disclosed transaction in the current window is a purchase of 10,816 KMX shares on 2025-10-02, worth $500K, per SEC Form 4 filings.