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 00
How to use the guide
This guide describes what a small or medium-sized marketplace owner needs to decide, build, show to users, and archive. It is not a code specification. It assumes the sale of physical goods to consumers in Poland, with the possibility of allowing sellers from other EU or non-EU countries.
The document covers common requirements for a typical marketplace: consumer law, pricing and reviews, GPSR and product safety, DSA, P2B, GDPR/RODO, cookies and marketing, DAC7, BDO and packaging, payments, VAT, accessibility, and cybersecurity. Regulated goods - for example, food, cosmetics, toys, electronics, medical devices, alcohol, or chemicals - require an additional industry-specific gateway described in Chapter 7.
One pattern for each obligation#
Each chapter should be read in the same order:
- Who it concerns - whether the obligation applies to the operator now, only after crossing a threshold, or primarily to the seller.
- What result is required - e.g., the ability to accept a report, restore a version, block an offer, or find buyers.
- The simplest MVP - using an existing form, order record, offer status, change history, file, or controlled spreadsheet, if it provides the required result.
- What proof to keep - content, time, source, decision, and action taken within the appropriate scope for the matter.
- When to expand - a dedicated panel, separate table, automation, integration, and dashboard appear only when scale, response time, permissions, or a specific regulation requires it.
A principle that removes 'room for interpretation' from platform operations#
The law often depends on facts. Therefore, the platform should not guess. It should use three states:
- APPROVED - required information and evidence are complete, and the product falls within the approved category.
- TO BE COMPLETED - sales are blocked until the seller provides the missing evidence or corrects the offer.
- REQUIRES SPECIALIST DECISION - sales remain blocked, and a lawyer, tax advisor, or product specialist resolves the specific case. The decision is recorded and applied to all identical cases.
Four layers of responsibility#
| Layer | Who is responsible | What it means for the platform |
|---|---|---|
| Contract with the buyer | Usually the seller indicated in the offer and at checkout | The platform shows who is selling, forwards the order, and handles communication; it cannot imply it is the seller itself if it is not. |
| Marketplace service | Platform operator | Responsible for platform terms and conditions, accounts, ranking, moderation, interface, service security, part of GDPR/RODO, DSA/P2B, and DAC7. |
| Product | Manufacturer, importer, distributor, and other relevant economic operator; sometimes also the operator | The platform collects and displays required information, blocks non-compliant offers, responds to reports and recalls. Own brand, import, or fulfillment may increase the operator's responsibility. |
| Payment and payout | Licensed payment provider and parties indicated in agreements | The operator uses a marketplace/split payment solution. It does not store customer funds in a regular account and does not pay them out to sellers without regulatory analysis. |
Glossary of simple roles#
- Operator - the company running the marketplace service.
- Seller - the entity with whom the buyer enters into a sales agreement. It can be a business or a private individual, if the platform allows it.
- Manufacturer - an entity that produces a product or commissions its design/production and offers it under its own name or brand. A craftsperson making a mug is a manufacturer.
- Importer - an entity based in the EU that first places a product from a third country on the EU market.
- Distributor - an entity making a product available in the supply chain, but not being the manufacturer or importer.
- Responsible person in the EU - for some products, an entity based in the EU whose details must accompany the offer and product when the manufacturer is outside the EU.
- Packaged product placer - an entity that, in situations defined by law, is the first to make a packaged product available in Poland, imports it, or packages a product before placing it on the market. This is a BDO role, not a synonym for seller.
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