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, reviews and repeat behaviour shape assortment, pricing and content. The hub sends pricing and bundle tests back.
Lifetime value can also be built on the platform itself, with brand stores, subscriptions and offers for repeat buyers. Always within each platform's rules: no inserts or codes that steer marketplace buyers to buy elsewhere.
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.
4 updates and this week's reading list on Marketplaces, every item linked to its source.