O'SULLIVAN MICHAEL J. (See Remarks) purchased 73.6% of their position (488.00 shares) of BERKSHIRE HATHAWAY INC on the open market
Open‑market purchase worth $250.1K — a major conviction buy. The strongest form of insider conviction signal.
P · 3 purchases
Filed: 8/13/2026ACC: 0001193125-26-349574
Officer· See Remarks
Since May 2026
+488.00
Net shares
Net buyer
$250.1K
Total acquired
3
Open market trades
3B · 0S
3
Total transactions
488.00 acquired
Non-Derivative Transactions3
Class B Common Stock
Indirect
Shares
+45.00
Price / share
$510.64
Trade value
$22.98K
% of position
6.8%
8/12/2026
663.00→708.00
Class B Common Stock
Indirect
Shares
+400.00
Price / share
$512.52
Trade value
$205.01K
% of position
56.5%
8/12/2026
708.00→1.11K
Class B Common Stock
Indirect
Shares
+43.00
Price / share
$513.61
Trade value
$22.09K
% of position
3.9%
8/12/2026
1.11K→1.15K
Total
Net shares
+488.00
Net value
$250.07K
| Security | Date | Type | Shares | Price / Share | Trade Value | % of Position | Held Before | Held After |
|---|---|---|---|---|---|---|---|---|
| Class B Common Stock Indirect | 8/12/2026 | P · Purchase | +45.00 | $510.64 | $22.98K | 6.8% | 663.00 | 708.00 |
| Class B Common Stock Indirect | 8/12/2026 | P · Purchase | +400.00 | $512.52 | $205.01K | 56.5% | 708.00 | 1.11K |
| Class B Common Stock Indirect | 8/12/2026 | P · Purchase | +43.00 | $513.61 | $22.09K | 3.9% | 1.11K | 1.15K |
| Total | +488.00 | $250.07K | ||||||
Derivative Transactions0
No derivative transactions reported