Which of the following is NOT a characteristic of a Sell Side Platform (SSP)?

The answer hinges on understanding the primary functions and objectives of a Sell Side Platform (SSP). An SSP is primarily designed for publishers, allowing them to manage and sell their ad inventory through various networks and exchanges. It is not limited to serving advertisers exclusively; rather, it focuses on facilitating the sale of ad space for the publishers who utilize the platform.

The aggregation of ad impression inventory is a fundamental characteristic of an SSP, as it brings together various publisher inventories to maximize the available ad space. Management of ad network services for publishers is also a critical feature, enabling publishers to organize and optimize their partnerships with ad networks. Additionally, an SSP's role in optimizing yield for publishers is essential for maximizing revenue from their inventory, making it vital for their operational efficiency.

Therefore, since the SSP does not serve advertisers exclusively but rather acts on behalf of publishers, this distinguishes it from other platforms or tools that may have a direct focus on advertisers.