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 24
Sources and Update Principle
Priority was given to applicable legal acts and materials from relevant authorities, not law firm blogs. Links accompanying chapters lead to the sources used for operational rules. At least once per quarter, the compliance owner checks for changes and updates the document, regulations, processes, and functionalities.
Cross-cutting Sources#
- EUR-Lex - GPSR, Regulation (EU) 2023/988
- EUR-Lex - DSA, Regulation (EU) 2022/2065
- EUR-Lex - P2B, Regulation (EU) 2019/1150
- EUR-Lex - GDPR, Regulation (EU) 2016/679
- UOKiK - Consumer Rights and Platform Changes
- Ministry of Finance - DAC7/DPI
- BDO - Official Service
- EUR-Lex - PPWR, Regulation (EU) 2025/40
- UODO - Guides and Decisions
- Ministry of Digital Affairs - Polish Accessibility Act
- Ministry of Digital Affairs - Amendment to KSC/NIS2
How to Update Without Chaos#
- Record changes in law or new interpretations by authorities.
- Indicate which roles, categories, screens, terms, and evidence are affected.
- Decide on the deadline and transition period.
- Modify functionalities, operational instructions, and documents as a single package.
- Test with user scenarios and offers.
- Notify sellers of the change in advance, as required by P2B, unless a legal exception applies.
- Retain the old version and proof of entry into force.
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