Guide chapters
00 - How to use the guide01 - First choose the business and responsibility model, then build the marketplace02 - Construction plan: what must exist and when03 - Responsibility Matrix: Operator, Seller, and Suppliers04 - Seller Onboarding: Whom to Allow to Sell05 - Product card: information without which an offer cannot be published06 - GPSR: Product Safety in Practice07 - Product Category Gates08 - BDO, packaging, and EPR: who is actually responsible09 - Consumer Law: Sale, Withdrawal, and Complaint10 - Prices, Promotions, Ranking, Advertising, and Reviews11 - Payments, Payouts, VAT, and Sales Documents12 - GDPR without myths: what to record, where, and on what basis13 - DSA: reporting, moderation, and seller traceability14 - P2B: fair rules for business users15 - DAC7: seller data and annual reporting16 - E-commerce accessibility from June 28, 202517 - Cybersecurity and KSC/NIS218 - Retention: How long to store data and evidence19 - Post-launch operations: calendar and owners20 - Four business models - specific decisions21 - Document and Procedure Package to Prepare22 - GO / NO-GO Checklist Before Launch23 - Most Common Misconceptions24 - Sources and Update Principle§ - Important Disclaimer Regarding the Nature of the Material
Chapter 03
Responsibility Matrix: Operator, Seller, and Suppliers
| Area | Marketplace Operator | Seller | External Supplier |
|---|---|---|---|
| Seller Identity | Collects or obtains only data required for its own obligations from the PSP source, verifies remaining elements, and archives proof | Provides true, up-to-date data and documents | PSP performs KYC and may be a data source; the operator does not duplicate it unnecessarily but remains responsible for missing DSA/DAC7 elements |
| Sales Agreement | Indicates the party to the agreement, forwards the order and proof | Is a party, carries out delivery, withdrawal, and complaint handling | Courier carries out transport according to its role |
| Product Compliance | Designs mandatory fields, checks, reacts, blocks, and cooperates | Provides information and proof; is responsible according to the role of manufacturer/importer/distributor | Laboratory or representative may provide proof; does not automatically assume responsibility |
| Price and Promotion | Ensures correct interface, price history, consistency, and markings | Sets the correct price and declares promotions according to the rules | Pricing tool operates within the limits set by the operator |
| Personal Data | Controller of its own processes; limits access, fulfills rights, and ensures security | Separate controller for data needed for its sales | Processor or separate controller according to the actual role |
| Payment | Integrates PSP, reconciles refunds and information flow | Undergoes PSP onboarding, receives payouts, and bears agreed costs | Licensed PSP handles accounts, settlement, payment KYC, and part of fraud |
| BDO/Packaging | Checks seller's declaration and BDO; responsible for its own goods, imports, or fulfillment | Defines its role and accounts for packaging/products it is responsible for | Fulfillment must report packaging consumption to the relevant responsible entity |
| DAC7 | Determines operator status, collects, verifies, reports, and informs | Provides data and updates it | PSP may be a source of some data based on the agreement and agreed integration |
| Moderation and Reports | Manages the reporting channel, decisions, justifications, and appeal path | Reacts, corrects the offer, provides proof | Moderation tool supports, but responsibility for the decision remains with the operator |
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