| 2004-12-02 | ZENITH NATIONAL INSURANCE CORP | A | +5,000 sh | — | — | 20,948 |
| 2004-11-05 | ZENITH NATIONAL INSURANCE CORP | M | +30K sh | $19.16 | +$575K | 37,948 |
| 2004-11-05 | ZENITH NATIONAL INSURANCE CORP | S | ▼−600 sh | $43.01 | ▼−$25.8K | 37,348 |
| 2004-11-05 | ZENITH NATIONAL INSURANCE CORP | S | ▼−4,200 sh | $43.02 | ▼−$181K | 33,148 |
| 2004-11-05 | ZENITH NATIONAL INSURANCE CORP | S | ▼−1,300 sh | $43.03 | ▼−$55.9K | 31,848 |
| 2004-11-05 | ZENITH NATIONAL INSURANCE CORP | S | ▼−3,100 sh | $43.04 | ▼−$133K | 28,748 |
| 2004-11-05 | ZENITH NATIONAL INSURANCE CORP | S | ▼−500 sh | $43.05 | ▼−$21.5K | 28,248 |
| 2004-11-05 | ZENITH NATIONAL INSURANCE CORP | S | ▼−200 sh | $43.06 | ▼−$8,612 | 28,048 |
| 2004-11-05 | ZENITH NATIONAL INSURANCE CORP | S | ▼−200 sh | $43.07 | ▼−$8,614 | 27,848 |
| 2004-11-05 | ZENITH NATIONAL INSURANCE CORP | S | ▼−1,300 sh | $43.08 | ▼−$56K | 26,548 |
| 2004-11-05 | ZENITH NATIONAL INSURANCE CORP | S | ▼−100 sh | $43.09 | ▼−$4,309 | 26,448 |
| 2004-11-05 | ZENITH NATIONAL INSURANCE CORP | S | ▼−1,400 sh | $43.10 | ▼−$60.3K | 25,048 |
| 2004-11-05 | ZENITH NATIONAL INSURANCE CORP | S | ▼−100 sh | $43.11 | ▼−$4,311 | 24,948 |
| 2004-11-05 | ZENITH NATIONAL INSURANCE CORP | S | ▼−100 sh | $43.12 | ▼−$4,312 | 24,848 |
| 2004-11-05 | ZENITH NATIONAL INSURANCE CORP | S | ▼−100 sh | $43.14 | ▼−$4,314 | 24,748 |
| 2004-11-05 | ZENITH NATIONAL INSURANCE CORP | S | ▼−1,100 sh | $43.16 | ▼−$47.5K | 23,648 |
| 2004-11-05 | ZENITH NATIONAL INSURANCE CORP | S | ▼−600 sh | $43.17 | ▼−$25.9K | 23,048 |
| 2004-11-05 | ZENITH NATIONAL INSURANCE CORP | S | ▼−1,300 sh | $43.18 | ▼−$56.1K | 21,748 |
| 2004-11-05 | ZENITH NATIONAL INSURANCE CORP | S | ▼−5,800 sh | $43.00 | ▼−$249K | 15,948 |
| 2004-11-05 | ZENITH NATIONAL INSURANCE CORP | M | −30K sh | — | — | 0 |
| 2004-05-26 | ZENITH NATIONAL INSURANCE CORP | A | +5,000 sh | — | — | 7,948 |