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 the European Union, with sellers based inside or outside the EU. Obligations that come from EU regulations apply the same way in every member state. Obligations that come from directives are implemented country by country, and where that distinction matters the guide uses Poland as the worked example.

The document covers common requirements for a typical marketplace: consumer law, pricing and reviews, GPSR and product safety, DSA, P2B, GDPR, cookies and marketing, DAC7, packaging and extended producer responsibility, 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:

1. Who it concerns - whether the obligation applies to the operator now, only after crossing a threshold, or primarily to the seller.
2. What result is required - e.g., the ability to accept a report, restore a version, block an offer, or find buyers.
3. The simplest MVP - using an existing form, order record, offer status, change history, file, or controlled spreadsheet, if it provides the required result.
4. What proof to keep - content, time, source, decision, and action taken within the appropriate scope for the matter.
5. 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#

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 on the market of a member state, imports it, or packages a product before placing it on the market. This is an EPR role, not a synonym for seller.