Berkshire Hathaway Inc (BRK-B) insider trading
Recent insider transactions reported to the SEC on Form 4 — directors and officers buying or selling their own company’s stock. Sourced directly from public SEC filings, latest filed Sep 29, 2026.
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- Filings shown
- 5
- Open-market buys
- 3
- Open-market sells
- 1
- Buys, 10b5-1 box not checked
- 3 of 3
Counts cover the 5 most recent Form 4 filings Tradune holds for BRK-B (filed Jul 15 – Sep 29, 2026); the score below covers only the trailing 90 days (3 buys, 1 sell). No completed check of BRK-B's Form 4 list on SEC EDGAR is on record yet; the latest BRK-B filing Tradune holds was filed Sep 29, 2026. This is not guaranteed to be the complete record — see BRK-B's full Form 4 filing history on SEC EDGAR.
Open-market activity, last 90 days
Purchases (Form 4 code P) and sales (code S) on the 4 filings Tradune holds for BRK-B filed Aug 13 – Sep 29, 2026. Grants, exercises, tax withholding and the other Form 4 transaction codes are left out.
1 open-market sale by Rule 10b5-1 checkbox
- On filings with the 10b5-1 box checked
- 0 sales· 0 sh
- checkbox disclosed
- On filings with the box not checked
- 1 sale· 39,700 sh
- not proof that no plan exists
- Not comparable
- 0 sales· 0 sh
- filed before Apr 1, 2023, or no checkbox value in the filing data
Counts are Form 4 lines as filed. The checkbox is one per filing, so every sale on a filing with the box checked is counted there even if only some of its transactions were under a plan; it records what the filer disclosed, and the three categories are not a judgement about why a sale was made.
| Insider | Buys | Sells | Shares bought | Shares sold | Value |
|---|---|---|---|---|---|
| Michael J. O'SullivanOfficer (see filing) | 3 | 0 | 488 | — | +$250,072 |
| Ajit JainVice Chairman | 0 | 1 | — | 39,700 | −$19,972,776 |
Value = shares × the price reported on each Form 4 (+ purchases, − sales); every open-market line in this window disclosed a price.
Summarises ~90 days of public SEC Form 4 activity — more distinct buyers, officer involvement and net buying score higher. A description of filing activity, not a rating or buy signal. How this score is computed →
How to read this: an open-market purchase (Form 4 code P) is a buy at the market price with the insider’s own money, as opposed to a grant, award or option exercise; an open-market sale is code S. When two or more distinct insiders report open-market purchases in the same 90-day window, this site labels that a cluster — a definition, not a forecast; see insider cluster buying. “Held after” is Form 4 Table I column 5; “Change” = shares ÷ holdings before the trade (held after − shares for an acquisition, held after + shares for a disposition).
Insider Buying at BRK-B
Insiders reported 3 open-market purchases of BRK-B between Jul 15, 2026 and Sep 29, 2026, across 1 distinct buyer. The most recent purchase was reported by Michael J. O'Sullivan (Officer (see filing)) on Aug 12, 2026. Grants, option exercises, and tax-withholding transactions are excluded from these counts.
Recent Form 4 filings
Source: SEC EDGAR Form 4 · transaction codes explained
| Transaction | Shares | Price | Held after | Change† | Date |
|---|---|---|---|---|---|
| Open-market sale 10b5-1 box not checked | 39,700 | $503.09 | 67,608 (indirect) | −37% | Sep 28, 2026 |
† change in this filer’s own reported holding line (Form 4 Table I, col. 5), not of total company ownership; small prior holdings produce large percentages, so under 100 shares the prior holding is shown instead.
“10b5-1 box checked” = the filer checked the Form 4 box stating that a transaction on the filing was made under a plan intended to satisfy Rule 10b5-1(c); “10b5-1 box not checked” = the box was left blank, which does not prove that no plan exists. The box applies to Form 4s filed from April 1, 2023; older filings, and boxes we could not read, carry no tag. What the 10b5-1 box means.
| Transaction | Shares | Price | Held after | Change† | Date |
|---|---|---|---|---|---|
| Gift | 10 | — | 317 | −3.1% | Sep 3, 2026 |
| Transaction | Shares | Price | Held after | Change† | Date |
|---|---|---|---|---|---|
| Open-market purchase 10b5-1 box not checked | 400 | $512.52 | 1,108 (indirect) | +56% | Aug 12, 2026 |
| Open-market purchase 10b5-1 box not checked | 43 | $513.61 | 1,151 (indirect) | +3.9% | Aug 12, 2026 |
| Open-market purchase 10b5-1 box not checked | 45 | $510.64 | 708 (indirect) | +6.8% | Aug 12, 2026 |
| Transaction | Shares | Price | Held after | Change† | Date |
|---|---|---|---|---|---|
| Derivative purchase Class A Common Stock | 1 | $765,184.18 | — | — | Aug 12, 2026 |
| Derivative purchase Class A Common Stock | 1 | $765,189.94 | — | — | Aug 12, 2026 |
| Transaction | Shares | Price | Held after | Change† | Date |
|---|---|---|---|---|---|
| Gift | 1,000,000 | — | — | — | Jul 14, 2026 |
| Gift | 9,000,000 | — | — | — | Jul 14, 2026 |
| Conversion of derivative | 12,000,000 | — | — | — | Jul 14, 2026 |
Insider filings reported around the same time
Other companies whose most recent Form 4 was filed closest to BRK-B's (Sep 29, 2026).
Frequently asked about BRK-B insider activity
How many insiders bought BRK-B stock in these Form 4 filings?
1 distinct insider at Berkshire Hathaway Inc reported 3 open-market purchases (Form 4 code P) of BRK-B shares between Jul 15, 2026 and Sep 29, 2026, the most recent filed by Michael J. O'Sullivan (Officer (see filing)) on Aug 12, 2026. Grants, option exercises, and tax-withholding transactions are excluded from these counts.
Who filed the most recent Form 4 for BRK-B?
The most recent Form 4 on this page was filed by Ajit Jain (Vice Chairman) on Sep 29, 2026, reporting 1 transaction. The original document is linked from the filing list above on SEC EDGAR. Amended filings (Form 4/A) may later revise reported figures.
What was the largest open-market BRK-B insider sale shown?
The largest open-market sale among the filings shown was 39,700 BRK-B shares at $503.09 (about $19,972,776) by Ajit Jain (Vice Chairman) on Sep 28, 2026. Value is shares × the price reported on the Form 4; its Rule 10b5-1 box is not checked.
Do the recent BRK-B insider purchases have the Form 4 10b5-1 box checked?
No. All 3 BRK-B open-market purchases shown were reported with the Rule 10b5-1 box not checked. A blank box records what the filer disclosed; it does not prove that no plan exists. Latest: Michael J. O'Sullivan (Officer (see filing)) on Aug 12, 2026, 45 shares.
New to Form 4s? The transaction codes, the 90-day window and the 0–100 score are defined on the insider-activity score methodology page.
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Track BRK-B insider filings free →This score summarizes SEC Form 4 filing activity over the trailing 90 days. It is descriptive, not predictive — not a rating, recommendation, or investment advice. Data: SEC EDGAR (public domain), as filed; amendments may revise figures. Tradune is not a registered investment adviser.
Data as filed; amended filings (Form 4/A) may revise figures. Sales may occur under prearranged Rule 10b5-1 trading plans.