---
title: "POST /v4/advertisers/{+advertiserId}/lineItems/{+lineItemId}:duplicate"
method: POST
path: "/v4/advertisers/{+advertiserId}/lineItems/{+lineItemId}:duplicate"
tags: ["advertisers"]
---

# POST /v4/advertisers/{+advertiserId}/lineItems/{+lineItemId}:duplicate

`POST /v4/advertisers/{+advertiserId}/lineItems/{+lineItemId}:duplicate`

## Request

- Base URL: `https://displayvideo.googleapis.com`
- URL: `https://displayvideo.googleapis.com/v4/advertisers/{+advertiserId}/lineItems/{+lineItemId}:duplicate`
- Auth: OAuth 2 (implicit, authorization URL `https://accounts.google.com/o/oauth2/auth`, scopes: `https://www.googleapis.com/auth/display-video`) and OAuth 2 (authorization code, authorization URL `https://accounts.google.com/o/oauth2/auth`, token URL `https://accounts.google.com/o/oauth2/token`, scopes: `https://www.googleapis.com/auth/display-video`)

Duplicates a line item. Returns the ID of the created line item if successful. YouTube & Partners line items cannot be created or updated using the API. **This method regularly experiences high latency.** We recommend [increasing your default timeout](/display-video/api/guides/best-practices/timeouts#client_library_timeout) to avoid errors.

## Path parameters

- `advertiserId` string, required
- `lineItemId` string, required

## Request body

- DuplicateLineItemRequest: Request message for LineItemService.DuplicateLineItem.
  - `containsEuPoliticalAds` 'EU_POLITICAL_ADVERTISING_STATUS_UNKNOWN' | 'CONTAINS_EU_POLITICAL_ADVERTISING' | 'DOES_NOT_CONTAIN_EU_POLITICAL_ADVERTISING': Whether this line item will serve European Union political ads. If contains_eu_political_ads has been set to `DOES_NOT_CONTAIN_EU_POLITICAL_ADVERTISING` in the parent advertiser, then this field will be assigned `DOES_NOT_CONTAIN_EU_POLITICAL_ADVERTISING` if not otherwise specified. This field can then be updated using the UI, API, or Structured Data Files. This field must be assigned when creating a new line item. Otherwise, **the `advertisers.lineItems.create` request will fail**.
  - `targetDisplayName` string: The display name of the new line item. Must be UTF-8 encoded with a maximum size of 240 bytes.

## Response `200`

Successful response

## Changes

- **2026-10-10** `52cdb4885336`: 2 breaking
  - removed the request body
  - removed the media type `*/*` for the response with the status `200`

[Operation history](https://skmtc.dev/google/apis/displayvideo/changes/v4/advertisers/:advertiserId/lineItems/:lineItemId:duplicate/post.md)

---

[API](https://skmtc.dev/google/apis/displayvideo.md) - [All operations](https://skmtc.dev/google/apis/displayvideo/llms.txt) - [OpenAPI document](https://skmtc.dev/google/apis/displayvideo/revisions/6329126f9fb6?raw)