First-order effects

• Amazon captured a larger share of online orders in the two weeks before Christmas than during the Thanksgiving and Black Friday period, concentrating late-holiday demand on its marketplace and fulfillment operations.
• Third-party merchants selling through Amazon gain exposure to the higher-volume final shopping window, while rival retailers receive a smaller share of that order flow.

Second-order effects

• Retailers and marketplaces competing for last-minute purchases face greater pressure to match dependable delivery promises, inventory availability, and fulfillment execution rather than rely on Black Friday promotions alone.
• A larger late-season Amazon order share increases the operational importance of its logistics capacity and its role as the fulfillment channel for marketplace sellers.

Third-order effects

• If this seasonal concentration persists, holiday e-commerce competition will increasingly turn on control of delivery networks and the ability to convert last-minute demand, reinforcing the advantage of platforms with integrated retail and logistics.
• The pattern could make route share a more consequential measure of platform power than promotional-day sales snapshots, though one holiday data point cannot establish a lasting shift.