Quick Start – Launch a Multi-Seller Campaign via MPO

What you’ll accomplish

In this guide, you will:

Take a set of existing marketplace sellers and activate them in an MPO Multi-Seller campaign.
Create seller-campaigns that link each seller to the shared campaign.
Set per-seller campaign bids (CPC) to control delivery.
Verify that the campaign is live by checking Multi-Seller statistics.

This flow assumes you are using MPO in Multi-Seller mode (shared campaign for many sellers). If you need one dedicated campaign per seller, use the Single-Seller Quick Start instead.

Who this recipe is for

This recipe is intended for:

Marketplace integrators and technical leads wiring MPO into their own tools.
Developers who want a concrete, end-to-end example of enabling Multi-Seller via API.
Teams onboarding many long-tail or small-budget sellers into a shared MPO campaign.

Prerequisites

Before starting, make sure all of the following are true.

Feature enablement & account setup

Your marketplace is onboarded to Marketplace Performance Outcomes (MPO).
MPO in Multi-Seller mode is enabled for your partner / advertiser by Criteo (at the partner level).

Work with your Criteo contact to confirm that:

Marketplace Performance Outcomes (MPO) is active for your partner, and
At least one Multi-Seller MPO campaign is configured for your advertiser, including:
- Optimization goal and bidding strategy.
- Targeting and creatives.

API access & permissions

Your application is onboarded to Criteo Marketing Solutions.
You can obtain an OAuth2 access token.
For Multi-Seller usage, the application has at least:
- Campaign – Manage permission on the relevant advertiser.

Refer to the general Onboarding Checklist on the Developer Portal for full scope and token setup.

Catalog & sellers

Your product catalog is integrated and includes seller information (for example a seller_id or equivalent field on products).
On the Criteo side, this seller field is mapped and activated for MPO so that:
- Sellers can be ingested from the catalog, and
- Exposed via the Sellers endpoints:


GET /marketplace-performance-outcomes/sellers

Sellers have already been ingested by MPO and exposed via the Sellers endpoint:

GET /marketplace-performance-outcomes/sellers

You should be able to list sellers and see sellerId values for the merchants you want to activate.

Step 1 – Discover sellers and confirm they’re available

First, retrieve the list of sellers available to your MPO advertiser and confirm the sellers you want to activate in Multi-Seller are present.

1.1 List sellers

Endpoint

GET /marketplace-performance-outcomes/sellers

You can filter by sellerName, which typically corresponds to the seller identifier from your product data (for example, the seller_id you send in the catalog), or by advertiser if needed.

Example – filter by sellerName


GET  https://api.criteo.com/{version}/marketing-solutions/marketplace-performance-outcomes/sellers?
sellerName=YourSellerName
Authorization: Bearer <ACCESS_TOKEN>
Accept: application/json

Sample response (simplified)

[
{
"id": "42171358",
"sellerName": "YourSellerName"
}
]

id is the sellerId you will use in the rest of the flow.
sellerName typically corresponds to the seller identifier coming from your product data (for example the seller_id or merchant ID you send in the catalog), so you can match MPO sellerId back to your own seller records.

Repeat this for each seller you plan to include in the Multi-Seller campaign and store the mapping between your internal seller identifier and MPO sellerId.

Step 2 – Link sellers to your Multi-Seller campaign (create seller-campaigns)

A seller-campaign represents the relationship between:

A seller (sellerId), and
A Multi-Seller campaign (campaignId),

including the bid and status for that seller in that campaign.

In most setups:

The Multi-Seller campaign already exists (configured by Criteo).
Your job is to create or confirm the seller-campaigns for the sellers you want active.

2.1 Get the campaign ID

Your Criteo contact will provide the Multi-Seller campaignId to use with MPO.
Keep this value as campaignId in the following examples.

2.2 Create a seller-campaign for a seller

You can create seller-campaigns for a seller via:


POST  https://api.criteo.com/{version}/marketing-solutions/marketplace-performance-outcomes/sellers/{sellerId}/seller-campaigns
Authorization: Bearer <ACCESS_TOKEN>
Content-Type: application/json
Accept: application/json

Example request

{
"campaignId": 123456,
"bid": 1.20
}

campaignId – the ID of your Multi-Seller MPO campaign.
bid – initial CPC bid for this seller in the campaign (in the campaign’s currency).

Example response (simplified)

{
"id": "42171358.123456",
"sellerId": "42171358",
"campaignId": 123456,
"bid": 1.20,
"suspendedSince": null,
"suspensionReasons": []
}

id is the sellerCampaignId (often a composite of seller and campaign).
A seller-campaign is active when:
- bid is positive, and
- suspendedSince is null (no active suspension reason).

If your account already has seller-campaigns for a given seller and campaign, you can skip creation and move directly to updating bids (next step).

Step 3 – Set or adjust bids for each seller-campaign

Once the seller-campaign exists, you can update the CPC bid to control how aggressively that seller participates in the Multi-Seller campaign.

3.1 Retrieve the seller-campaign (optional)

To confirm current configuration:


GET  https://api.criteo.com/{version}/marketing-solutions/marketplace-performance-outcomes/seller-campaigns/{sellerCampaignId}
Authorization: Bearer <ACCESS_TOKEN>
Accept: application/json

Sample response:


{
"id": "42171358.123456",
"sellerId": "42171358",
"campaignId": 123456,
"bid": 1.20,
"suspendedSince": null,
"suspensionReasons": []
}

3.2 Update the bid

To change the bid (for example, from 1.20 to 1.55):

PATCH  https://api.criteo.com/{version}/marketing-solutions/marketplace-performance-outcomes/seller-campaigns/{sellerCampaignId}
Authorization: Bearer <ACCESS_TOKEN>
Content-Type: application/json
Accept: application/json

Request body

{
"bid": 1.55
}

Guidelines:

Positive bid → seller-campaign can be active (subject to budgets and other constraints).
Bid = 0 → effectively pauses this seller in the campaign (no delivery for this seller).

You can repeat this per seller-campaign to:

Boost high-value sellers.
Reduce exposure for low-performing sellers.
Pause a seller temporarily by setting bid to 0.

Step 4 – Ensure budgets are in place

Multi-Seller campaigns require sufficient budget to deliver for all active sellers.

There are two budget surfaces in MPO:

Campaign-level or advertiser-level budgets
- Usually managed with your Criteo team or via generic Marketing Solutions budget APIs.
- Ensure at least one active budget is configured for the MPO campaign.
Seller-campaign budgets (optional, for finer control)
- Accessible via:
- ```
GET /marketplace-performance-outcomes/seller-campaigns/{sellerCampaignId}/budgets
GET /marketplace-performance-outcomes/budgets
POST /marketplace-performance-outcomes/budgets
```
  - These can be used to set per-seller caps or schedule specific time windows. For a first Multi-Seller launch, it is often enough that:
  - The parent campaign budget is in place.
  - Your seller-campaign bids are positive. Work with your Criteo contact to decide whether you also need per-seller budgets at launch.
  Step 5 – Verify delivery with statistics
  Once:
  - Sellers are correctly ingested,
  - Seller-campaigns exist with positive bids,
  - Budgets are active, you can verify delivery via the Standard Reporting API.
  5.1 Check campaign-level stats

GET  https://api.criteo.com/{version}/marketing-solutions/marketplace-performance-outcomes/stats/campaigns?campaignId=123456&startDate=2026-03-01&endDate=2026-03-01
Authorization: Bearer <ACCESS_TOKEN>
Accept: application/json

Typical response (simplified):

{
"columns": [
"campaignId",
"day",
"impressions",
"clicks",
"cost",
"saleUnits",
"revenue",
"cr",
"cpo",
"cos",
"roas"
],
"data": [
[
"123456",
"2026-03-01",
3969032,
13410,
1111.295,
985,
190758099,
0.073,
1.128,
0.0,
171653.88
]
],
"rows": 1
}

5.2 Check per-seller performance

Use seller or seller-campaign stats to confirm each seller is delivering:

GET  https://api.criteo.com/{version}/marketing-solutions/marketplace-performance-outcomes/stats/sellers?campaignId=123456&startDate=2026-03-01&endDate=2026-03-01
Authorization: Bearer <ACCESS_TOKEN>
Accept: application/json

Or, for the most granular view:

GET  https://api.criteo.com/{version}/marketing-solutions/marketplace-performance-outcomes/stats/seller-campaigns?campaignId=123456&sellerId=42171358&startDate=2026-03-01&endDate=2026-03-01
Authorization: Bearer <ACCESS_TOKEN>
Accept: application/json

These endpoints return impressions, clicks, cost, and conversion metrics that you can surface in your own BI tools or seller portal.