<!-- source: https://secondlayer.tools/docs/api-reference#reorg-object -->

## The Reorg object

A fork the indexer rolled back. Rows inside `orphaned_range` were replaced; undo anything you committed from them.

| Field | Type | Description |
| --- | --- | --- |
| `id` | string | Reorg id. |
| `detected_at` | string · date-time | When the indexer saw the fork. |
| `fork_point_height` | integer | First block height the new fork replaced. Undo rows at or above it. |
| `old_index_block_hash` | string · nullable | Index block hash of the abandoned tip. |
| `new_index_block_hash` | string · nullable | Index block hash of the winning tip. |
| `orphaned_range` | object | First and last cursor of the rows that were replaced. |
| `new_canonical_tip` | string | Cursor of the new canonical tip. |

```json
{
  "id": "3f16c2c5-9551-4ae9-adb0-923668e5c65e",
  "detected_at": "2026-09-15T15:39:38.129Z",
  "fork_point_height": 8996511,
  "old_index_block_hash": "0x45ba0195071488eda13afa66d8ce8612558a739f781be5a032d96332797c4174",
  "new_index_block_hash": "0xa686ff58e7c5ccb26c850a7eaffa7e7274fcbc081c706344eb6f1e1446023df0",
  "orphaned_range": {
    "from": "8996511:0",
    "to": "8996512:2701"
  },
  "new_canonical_tip": "8996511:0"
}
```