A marketplace is a third-party platform such as Amazon, Zalando, Kaufland or Walmart Marketplace, where many sellers sell to the platform's customers. As a seller, the brand owns the sale and the price; the platform owns the customer and most of the data.
See this week's updatesMarketplaces are where a large share of online demand already shops. They bring reach and volume and let a brand monetise demand that exists today.
Their reviews, Q&A and aggregated analytics also show what shoppers search for, compare and buy again.
Marketplaces feed the hub with insight, not personal data: search terms, baskets and reviews shape assortment, pricing and content. Lifetime value can also be built on the platform itself, always within each platform's rules: no inserts or codes that steer marketplace buyers to buy elsewhere.
Shoppers search the platform
KPI Share of search
Content, images and Q&A
KPI Conversion rate
Price, stock and delivery win the offer
KPI Buy Box share
The first order with the brand
KPI New-to-brand customers
Ratings and Q&A feed back
KPI Ratings and reviews
Third-party sellers' share of physical gross merchandise sales on Amazon, from 1999 to 2018.
Amazon, 2018 Letter to Shareholdersof Amazon's worldwide paid units were sold by third-party sellers in Q2 2026.
Amazon, Q2 2026 results (SEC filing)of Zalando's B2C GMV came from its partner business in 2025, up from 10% in 2019, with 40 to 50% targeted for 2028.
Zalando, Business Update 2026To put it bluntly: Third-party sellers are kicking our first party butt. Badly.
5 updates and this week's reading list on Marketplaces, every item linked to its source.