# Deletes several unit of measure groups in one call.

`POST /inventory/unit-of-measure-groups/bulk-delete`

Group: Inventory › Unit of Measure Groups · Operation ID: `bulkDeleteUnitOfMeasureGroups`

All or nothing. Every identifier is resolved and checked for references before anything is deleted, so one unknown identifier or one group still in use fails the whole call and nothing is deleted. A group must be empty first: reassign any items and remove its conversion lines, the base unit's line included, with deleteLines on PATCH inventory/unit-of-measure-groups/:id. Use DELETE inventory/unit-of-measure-groups/:id to delete a single group.

[Open in the interactive reference](https://docs.api.lensing.ai/?op=bulkDeleteUnitOfMeasureGroups)

## Parameters

| Name | In | Type | Required | Description |
| --- | --- | --- | --- | --- |
| `Api-Version` | header | `"v1"` | yes | The API version this request targets, named by its public identifier. Required on every request; omitting it, or naming a version this company does not have, is answered with 400. This document describes version `v1`. |
| `Idempotency-Key` | header | string | no | An opaque caller-chosen string (1-255 characters) that makes this request safe to retry. Repeating the same key with an identical request body replays the original response instead of re-executing - but only once that original request succeeded; a failed attempt re-executes on retry. Repeating the key with a different body is answered with 422. A key still in flight is answered with 409 - as is a key whose original request was interrupted before it finished, for a few minutes afterwards, until that attempt is presumed dead. A completed response stays replayable for 24 hours. The key is scoped to the caller, not to the action: reusing it for a different action is answered with 409 or 422 rather than treated independently. On read actions this header is ignored. On write actions that cannot offer the guarantee it is answered with `400 IDEMPOTENCY_NOT_SUPPORTED` rather than silently ignored. |

## Request body

Required, `application/json`: bulkDeleteUnitOfMeasureGroupsInput.

| Field | Type | Required | Description |
| --- | --- | --- | --- |
| `ids` | array of string | yes | The unique identifiers for the unit of measure groups to delete. Each must already be empty, with no items pointing at it and no conversion lines left. If any identifier matches nothing or any group is still in use, nothing is deleted and the whole call fails. |

Example:

```json
{
  "ids": [
    "3b7d5e9c-1a24-4f80-9c6d-2e8f70b13a45",
    "e57a0d34-9f62-4b18-bc25-71a6e8039d4b"
  ]
}
```

## Response

`200` Success

Under `data` (bulkDeleteUnitOfMeasureGroupsOutput):

| Field | Type | Required | Description |
| --- | --- | --- | --- |
| `deleted` | array of object | yes | The deleted unit of measure groups, in the same order as the input. Match entries to inputs by index. |
| `deleted[].id` | string | yes | The unique identifier for the deleted unit of measure group. |
| `deleted[].name` | string | yes | The display name the deleted unit of measure group held. |

## Response headers

- `Idempotency-Replayed` — Present and `true` only when this response replays a previously stored one for the same Idempotency-Key, rather than reflecting a live execution. Absent on a live response - never sent as `false`.

## Errors

| Code | Status |
| --- | --- |
| `NOT_FOUND` | 400 |
| `UNIT_OF_MEASURE_GROUP_IN_USE` | 400 |
| `IDEMPOTENCY_KEY_CONFLICT` | 409 |
| `IDEMPOTENCY_PAYLOAD_MISMATCH` | 422 |

## Statuses

- `400` — Invalid request or business failure. Codes: NOT_FOUND, UNIT_OF_MEASURE_GROUP_IN_USE
- `401` — Missing or invalid access token
- `403` — Not authorized
- `404` — Not found
- `409` — The Idempotency-Key is still being processed by another request.
- `422` — The Idempotency-Key was already used with a different request payload.
- `429` — Too many requests
- `500` — Internal server error