Insider trades › Michael J. O'Sullivan
Michael J. O'Sullivan
A corporate insider: an officer, director or owner of more than 10% of a company. Insiders report their trades to the SEC on Form 4The form insiders use to report each purchase or sale of their company's stock. It is due within two business days of the trade. · Last filing Aug 13, 2026
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Using 13F.ai, list Michael J. O'Sullivan's open-market buys and sells across companies in the last two years, with the Form 4 links.
Using 13F.ai, how did the stocks Michael J. O'Sullivan bought perform after the purchase compared with the S&P 500?
Using 13F.ai, are other insiders at the same companies buying or selling at the same time as Michael J. O'Sullivan?
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Buying and selling by quarter
Dollars bought and sold on the open market over the last two years.
Bought Sold
By trade date, using the shares and price reported for each trade. Stock grants, option exercises and shares withheld for tax are left out.
Roles
The companies where this person reports as an insider, and their position at each, most recent first.
Latest open-market trades
Purchases and sales at every company, most recent filing first.
| How the stock has done since the trade date, measured against the S&P 500 over the same days. It describes the stock, not the trader's actual gain or loss. | Filing | ||||||
|---|---|---|---|---|---|---|---|
| Aug 12, 2026 | BRK.B Berkshire Hathaway Inc. Class B | Buy | 45 | $510.64 | $23.0K | +18.6% | Form 4 ↗ |
| Aug 12, 2026 | BRK.B Berkshire Hathaway Inc. Class B | Buy | 400 | $512.52 | $205.0K | +18.6% | Form 4 ↗ |
| Aug 12, 2026 | BRK.B Berkshire Hathaway Inc. Class B | Buy | 43 | $513.61 | $22.1K | +18.6% | Form 4 ↗ |
| May 6, 2026 | BRK.B Berkshire Hathaway Inc. Class B | Buy | 483 | $467.13 | $225.6K | +23.4% | Form 4 ↗ |
| May 6, 2026 | BRK.B Berkshire Hathaway Inc. Class B | Buy | 53 | $470.22 | $24.9K | +23.4% | Form 4 ↗ |
| Nov 17, 2025 | SNAP Snap Inc. | Sale | 70,882 | $8.34 | $591.2K | -49.0% | Form 4 ↗ |
| Oct 31, 2025 | SNAP Snap Inc. | Sale | 24,000 | $7.73 | $185.5K | -43.2% | Form 4 ↗ |
| Sep 30, 2025 | SNAP Snap Inc. | Sale | 24,000 | $7.86 | $188.6K | -45.0% | Form 4 ↗ |
| Sep 16, 2025 | SNAP Snap Inc. | Sale | 14,290 | $7.58 | $108.3K | -46.3% | Form 4 ↗ |
| Aug 29, 2025 | SNAP Snap Inc. | Sale | 24,000 | $7.16 | $171.8K | -43.3% | Form 4 ↗ |
| Aug 18, 2025 | SNAP Snap Inc. | Sale | 68,705 | $7.18 | $493.3K | -45.6% | Form 4 ↗ |
| Jul 31, 2025 | SNAP Snap Inc. | Sale | 24,000 | $9.57 | $229.7K | -63.6% | Form 4 ↗ |
| Jun 30, 2025 | SNAP Snap Inc. | Sale | 24,000 | $8.71 | $209.0K | -61.6% | Form 4 ↗ |
| Jun 16, 2025 | SNAP Snap Inc. | Sale | 14,297 | $8.04 | $114.9K | -61.6% | Form 4 ↗ |
| May 30, 2025 | SNAP Snap Inc. | Sale | 24,000 | $8.15 | $195.6K | -64.2% | Form 4 ↗ |
| May 16, 2025 | SNAP Snap Inc. | Sale | 68,845 | $8.59 | $591.4K | -66.8% | Form 4 ↗ |
| Apr 30, 2025 | SNAP Snap Inc. | Sale | 24,000 | $7.74 | $185.8K | -70.0% | Form 4 ↗ |
| Mar 31, 2025 | SNAP Snap Inc. | Sale | 24,000 | $8.60 | $206.4K | -74.5% | Form 4 ↗ |
| Mar 17, 2025 | SNAP Snap Inc. | Sale | 14,183 | $8.83 | $125.2K | -74.5% | Form 4 ↗ |
| Feb 28, 2025 | SNAP Snap Inc. | Sale | 24,000 | $10.16 | $243.8K | -75.6% | Form 4 ↗ |
| Feb 18, 2025 | SNAP Snap Inc. | Sale | 69,119 | $10.84 | $749.2K | -75.7% | Form 4 ↗ |
| Jan 31, 2025 | SNAP Snap Inc. | Sale | 18,000 | $11.49 | $206.8K | -78.8% | Form 4 ↗ |
| Dec 31, 2024 | SNAP Snap Inc. | Sale | 18,000 | $10.84 | $195.1K | -79.9% | Form 4 ↗ |
| Dec 16, 2024 | SNAP Snap Inc. | Sale | 56,961 | $11.44 | $651.6K | -77.9% | Form 4 ↗ |
| Nov 29, 2024 | SNAP Snap Inc. | Sale | 18,000 | $11.89 | $214.0K | -80.7% | Form 4 ↗ |
| Nov 18, 2024 | SNAP Snap Inc. | Sale | 12,315 | $10.54 | $129.8K | -78.4% | Form 4 ↗ |
| Oct 31, 2024 | SNAP Snap Inc. | Sale | 18,000 | $12.32 | $221.8K | -89.4% | Form 4 ↗ |
| Sep 30, 2024 | SNAP Snap Inc. | Sale | 18,000 | $10.81 | $194.6K | -82.3% | Form 4 ↗ |
Each row links to its Form 4. Since trade compares the stock’s move from the close on the trade date (or the next trading day) to its latest close with the S&P 500 over the same days, adjusted for splits and excluding dividends. It describes the stock, not what the trader made: we don’t know their purchase price, position size or later sales. A dash means the trade isn’t matched to a listed stock, or there is no closing price after it yet.
When several people report on the same filing, we list it under the first one named, so trades by someone usually listed second may be missing here. Information, not investment advice: see the disclaimer.