Abstract: There are two main sales channels for the e-commerce platform: (1) reseller channel, the manufacturer wholesales products to the e-commerce platform, the ownership of the products belongs to the e-commerce platform;(2) marketplace channel, the manufacturer opens a flagship store or a specialty store on the e-commerce platform to directly sell to the consumer, pays a certain commission fee to the e-commerce platform according to the product category, and the ownership of the product belongs to the manufacturer. In recent years, some e-commerce platforms (such as JD.com, Amazon, etc.) that initially only have reseller channel have introduced the marketplace channel. After the introduction of the marketplace channel, channels on the e-commerce platform are highly competitive. Since the e-commerce platform has ownership of reseller channel products, therefore, most e-commerce platforms increase the competitiveness of reseller channel through service investment.

Key words: marketplace channel introduction; e-commerce platform; service investment; game theory; two-part tariff