Q3 2026 E-Commerce Briefing: PSD3, Marketplace Fees and the AI Search Shakeup

Three stories matter this quarter. Not because they are loud, but because each one quietly changes who gets paid, how much, and who gets found. Here is the operator's version of each.

Europe: PSD3 gets real

The EU's next payments framework has moved from consultation papers to implementation planning, and processors are already adjusting onboarding and authentication flows ahead of the deadlines.

What it means for stores selling into Europe:

• Stronger authentication rules, with smarter exemptions: expect more low-friction 3DS on trusted traffic and harder checks on risky flows
• Tighter fraud liability, pushing PSPs to reward merchants with clean dispute metrics and punish the rest with reserves
• Open banking payments maturing as a real card alternative at checkout, with fees that undercut card rails

The move: get your dispute metrics clean now. Under the new regime, your fraud numbers become negotiating leverage on fees and reserves.

Marketplace fees keep climbing

The pattern repeats across the big marketplaces this year: fulfillment surcharges up, storage fees restructured, payout holds for new sellers stretched. Margins that penciled out in January need a second look in July.

The move: reprice against current fee tables, not the ones you launched with, and stop being a single-channel store. The reseller cases in our success stories exist because one suspension or one fee change should never be existential.

AI assistants are rewriting discovery

A growing slice of product discovery now happens inside AI assistants that compare options and answer with a shortlist. Stores are seeing search traffic flatten while assistant-referred sessions convert at striking rates, because the shopper arrives pre-sold.

The move, and it is very concrete:

1. Structured data everywhere: product schema, prices, availability and reviews marked up correctly is what assistants can actually read
2. Feeds in order: clean product feeds are becoming the new SEO surface
3. Be quotable: clear product pages with real specifications beat adjective soup when a machine is choosing the shortlist

The quarter in one line

Payments are getting stricter, marketplaces more expensive, and discovery more automated. Operators who tighten disputes, diversify channels and structure their data will take share from the ones who wait for the recap videos.