Understanding Index Marketplaces transactions for Marketplace Partners

Marketplace Partners
Last Updated: February 17, 2026

The Index Marketplace platform is designed so you earn a fee for providing your unique media offering, while also providing Media Owners with the highest revenue possible on every transaction. Unless otherwise specified, bids in Marketplaces compete net of fees, where fees are removed from the bid price before the auction is conducted, and the net bid price competes against a Media Owner's open market and private market demand. For more information about Index Marketplaces, see How Index Marketplaces work.

You can specify how you want to apply fees, either as a percentage of media spend or as a fixed-rate CPM fee. Auctions can compete as first price, where the highest bid wins and the winning bidder owes the winning bid price or as fixed price, where the winning bidder owes a negotiated fixed price.

Example: Percentage fee

The following diagram shows an example revenue share structure where you earn a percentage of media spend. In this example, a Marketplace has returned a gross bid of $10. The $10 gross bid (Marketplace Media Spend) minus a 5% Marketplace Owner Fee and a 15% Index revenue share with the Media Owner results in a net bid price of $8.08. The Marketplace competes in the Index auction using the net bid price of $8.08. If that Marketplace wins the auction and results in an impression, the Media Owner is paid $8.08, the Partner earns $0.50, and Index earns $1.42.

Visual of fee example

Example: Fixed-rate CPM fee

The following diagram shows an example revenue share structure where you earn a fixed CPM fee regardless of what the media spend is. In this example, a Marketplace has returned a gross bid of $10. The $10 gross bid (Marketplace Media Spend) minus a $1.00 CPM Marketplace Owner Fee and a 15% Index revenue share with the Media Owner results in a net bid price of $7.65. The Marketplace competes in the Index auction using the net bid price of $7.65. If that Marketplace wins the auction and results in an impression, the Media Owner is paid $7.65, the Partner earns $1.00, and Index earns $1.35.

Note: CPM fees are USD only. If using a fixed price auction, the CPM value must be lower than the fixed price for the deal ID to transact.

Visual of fee example

Marketplace types

Marketplace Partners can create either Standard or Custom Marketplaces.

Marketplace typeDescription

Standard Marketplaces

  • Index earns the Index revenue share negotiated directly with the Media Owner.
  • By default, Media Owners are opted in to all Standard Marketplaces and have the option to opt out at any time.

Custom Marketplaces

  • Unique terms or mechanics are negotiated between Marketplace Partners and Media Owners. Publishers may be required to opt in to these Marketplaces.

Marketplace fee transparency models

Partners can choose the level of fee transparency that they disclose for reporting metrics. A Marketplace can operate using a disclosed fee model or undisclosed fee model. The following table lists how metrics are disclosed in each model.

MetricDisclosed modelUndisclosed model
Media SpendAlways disclosedAlways disclosed for buyers, Undisclosed for Media Owners
Marketplace Media SpendAlways disclosedUndisclosed
Marketplace Total FeeAlways disclosedUndisclosed
Marketplace Owner FeeOptionally disclosedUndisclosed
Marketplace Publisher SpendAlways disclosedUndisclosed
Marketplace Vendor FeeOptionally disclosedUndisclosed

Marketplace reporting metrics

Publishers, buyers, DSPs, and Marketplace Partners can create reports in the Index UI, the Reporting API, or the CAL API that break down Marketplace spend and revenue shares and allow all parties involved in the transaction to reconcile their earnings. The following table lists all of the available Marketplace metrics:

MetricDefinition

Media Spend

The amount a buyer owes to Index for ad inventory purchased through the exchange.

Note: This metric is only available if the Marketplace Owner has opted to share this data.

Marketplace Media Spend

The portion of the Media Spend a buyer transacts through a Marketplace on the exchange.

Note: This metric only exists for impressions transacted through a Marketplace and is only available if the Marketplace Owner has opted to share this data.

Marketplace Total Fee

The total monetary fees taken within the Marketplace.

Note: This metric only exists for impressions transacted through a Marketplace and is only available if the Marketplace Owner has opted to share this data.

Marketplace Index Fee

Index's portion of the Marketplace Total Fee.

Note: As of April 24, 2025, the Marketplace Index Fee field has been deprecated. The feature to apply the Index fee at the Marketplace level instead of the Media Owner level has never been used. We have deprecated this functionality while maintaining the fields in existing reports for backwards compatibility.

Marketplace Owner Fee

Marketplace Owner's portion of the Marketplace Total Fee.

Marketplace Publisher Spend

The portion of the Marketplace Media Spend designated for the seller prior to the deduction of any additional fees approved by sellers.

Note: This metric only exists for impressions transacted through a Marketplace and is only available if the Marketplace Owner has opted to share this data.

Marketplace Owner Fee (%)

The Marketplace Owner's portion of the Marketplace Total Fee as a percent (as a decimal from 0 to 1) of Marketplace Media Spend. The calculation is:

Marketplace Owner Fee / Marketplace Media Spend

Note: This metric only exists for impressions transacted through a Marketplace and is only available if the Marketplace Owner has opted to share this data.

Marketplace Index Fee (%)

Index's portion of the Marketplace Total Fee as a percent (as a decimal from 0 to 1) of Marketplace Media Spend. The calculation is: Marketplace Index Fee / Marketplace Media Spend

Note: As of April 24, 2025, the Marketplace Index Fee (%) field has been deprecated. The feature to apply the fee at the level instead of the Media Owner level has never been used. We have deprecated this functionality while maintaining the fields in existing reports for backwards compatibility.

Marketplace Total Fee %

The total monetary fees taken within the Marketplace as a percent (as a decimal from 0 to 1) of Marketplace Media Spend. The calculation is:

Marketplace Total Fee / Marketplace Media Spend

Note: This metric only exists for impressions transacted through a Marketplace and is only available if the Marketplace Owner has opted to share this data.

Marketplace CPM

Marketplace Media Spend per 1000 Marketplace impressions. The calculation is:

(1000 x Marketplace Media Spend) / Marketplace Impressions

Note: This metric only exists for impressions transacted through a Marketplace and is only available if the Marketplace Owner has opted to share this data. .

Deal Media Spend

The amount a buyer owes to Index for private market (deal) ad inventory purchased through the exchange.

Note: Marketplace data is only available if the Marketplace Owner has opted to share this data.

Open Media Spend

The amount a buyer owes to Index for open market ad inventory purchased through the exchange.

Marketplace Vendor Fee

The Marketplace Vendor's portion of the Marketplace Total Fee.

Note: This metric only exists for impressions transacted through a Marketplace.

How does billing work?

For Standard Marketplaces, Index handles all payments within the Index Marketplace platform, making it easy for all parties within the transaction to get paid. For some Custom Marketplaces, you or Index may work with a Media Owner to agree on different terms.

To learn more about how to reconcile payments, see Reconcile your payments from Index by reviewing your performance metrics.