Insider buying report — Monday, September 21, 2026: 45 open-market buys worth $369.0M
On Monday, September 21, 2026 the SEC published 45 open-market insider purchases worth $369.0M across 37 companies, against 43 insider sales of $1M or more worth $545.7M. By dollar value the selling outweighed the buying, which is the usual state of affairs — executives at large companies sell on schedule, and buy only on purpose.
The largest purchase
Berkshire Hathaway Inc (10% owner) at LENNAR CORP /NEW/ (LEN, LEN.B) filed the day's largest purchase: 2,743,529 shares at $77.42, $212.4M in total, transacted on Sep 17, 2026 and filed Sep 21, 2026. What makes it notable: it is this insider's first open-market purchase on record.
Behind it: Tan Anthony Ping Yeow at GRAB ($29.9M), Monroe James III at GSAT ($29.8M), Cohen Ryan at GME ($26.4M).
Top ten insider buys
| Filed | Insider | Company | Type | Shares | Price | Value |
|---|---|---|---|---|---|---|
| 2026-09-21 | Berkshire Hathaway Incfirst buy 10% owner | LEN, LEN.B LENNAR CORP /NEW/ | Bought | 2,743,529 | $77.42 | $212.4M |
| 2026-09-21 | Tan Anthony Ping YeowCEOfirst buydip Chief Executive Officer | GRAB Grab Holdings Ltd | Bought | 10,350,000 | $2.89 | $29.9M |
| 2026-09-21 | Monroe James IIIfirst buy Director · 10% owner | GSAT Globalstar, Inc. | Bought | 361,600 | $82.52 | $29.8M |
| 2026-09-21 | Cohen RyanclusterCEOchairlargest ever President, CEO and Chairman | GME GameStop Corp. | Bought | 1,150,680 | $22.94 | $26.4M |
| 2026-09-21 | Lincoln Financial Investments Corplargest ever 10% owner | LNBIX Lincoln Bain Capital Total Credit Fund | Bought | 2,460,630 | $10.16 | $25.0M |
| 2026-09-21 | Conifer Management, L.L.C.dip 10% owner | GPI GROUP 1 AUTOMOTIVE INC | Bought | 65,650 | $256.78 | $16.9M |
| 2026-09-21 | Angermayer Christiandiplargest ever Director · 10% owner | ENHA Enhanced Group Inc. | Bought | 6,080,047 | $1.15 | $7.0M |
| 2026-09-21 | Life Insurance Co Nippon 10% owner | CRBG Corebridge Financial, Inc. | Bought | 174,760 | $35.20 | $6.2M |
| 2026-09-21 | de Oliveira Andre Luis Duarteclusterfirst buy Executive Officer | BBD BANK BRADESCO | Bought | 309,111 | $17.98 | $5.6M |
| 2026-09-21 | Halstead MichaelclusterCEOfirst buy Chief Executive Officer | CYBN CYBIN INC. | Bought | 100,000 | $13.47 | $1.3M |
Showing 10 of 45 open-market purchases filed on 2026-09-21. The full list, sortable and filterable by role and size, is in the members Filings Browser; the same rows are available as JSON through the API.
Signals in the day's buying
Of the purchases filed: 9 purchases by a chief executive (BOLT, BORR, CBKM, CULP, CYBN, EPSN); 4 by a CFO (BOLT, ELWT, HLEO, TLYS); 15 that belong to an active cluster (BBD, BORR, BUKS, CBKM, CYBN, GME); 24 first-ever purchases by the insider; 22 bought at least 25% below the recent high. These are the flags the members area scores on — a CFO buying with their own money has historically been the strongest single-insider signal, and a cluster of three or more buyers the strongest of all. The cluster guide explains the scoring.
GRAB — two years of insider activity on the price
GSAT — two years of insider activity on the price
GME — two years of insider activity on the price
Largest insider sales ($1M and up)
| Filed | Insider | Company | Type | Shares | Price | Value |
|---|---|---|---|---|---|---|
| 2026-09-21 | Zhao Peng Jonathan Chief Executive Officer | BZ Kanzhun Ltd | Sold | 15,170,000 | $7.25 | $110.0M |
| 2026-09-21 | Andreas Bechtolsheim 10% owner | ANET Arista Networks, Inc. | Sold | 300,000 | $198.95 | $59.7M |
| 2026-09-21 | Leproust Emily M. Chief Executive Officer | TWST Twist Bioscience Corp | Sold | 343,098 | $158.08 | $54.2M |
| 2026-09-21 | Goeckeler David Chairman & CEO | SNDK Sandisk Corp | Sold | 33,330 | $1,574.16 | $52.5M |
| 2026-09-21 | Lynch James F Director | GSAT Globalstar, Inc. | Sold | 361,600 | $82.52 | $29.8M |
The largest sale was Zhao Peng Jonathan at Kanzhun Ltd (BZ), $110.0M. Sales are shown from $1M upward only; below that they are overwhelmingly scheduled 10b5-1 plans and tax-driven, and listing them would bury the signal.
Context: the market-wide picture
For the week starting Sep 14, 2026, 26% of open-market insider filings across the whole market were buys (317 buys against 902 sales). The long-run average sits near a third, because insiders buy for one reason and sell for many. The full weekly series since 2019 is on the insider sentiment index.
Questions this post answers
Which insiders bought stock on Sep 21, 2026?
45 open-market purchases were filed with the SEC on Sep 21, 2026, worth $369.0M across 37 companies. The largest was Berkshire Hathaway Inc at LENNAR CORP /NEW/ (LEN, LEN.B), $212.4M. The ten largest are listed above.
Were insiders net buyers or net sellers on Sep 21, 2026?
By dollar value, sellers: $369.0M bought against $545.7M in sales of $1M or more. Selling normally dominates because executives sell on pre-set schedules; what matters is the buying, which is voluntary.
What counts as an insider buy here?
Only Form 4 transactions with code P — an open-market purchase paid for with the insider's own money. Grants (A), option exercises (M) and shares withheld for tax (F) are excluded, because they follow vesting schedules set years earlier and say nothing about what the insider thinks of the price.
How current is this?
The SEC publishes Form 4 filings through about 10 pm Eastern each business day. This report covers everything published on Sep 21, 2026 and was generated early the next morning from the same data the members area uses.