Marketplace compliance is what an operator owes because it stands between other people's sales and other people's money: seller due diligence, payment licensing, tax reporting and collection, product rules and consumer rights. The neutral-noticeboard defense stopped working in the EU, UK and US some years ago.
The line where holding buyer money becomes a regulated service
Receiving a buyer's payment and forwarding part of it to a seller is, on most readings, executing payment transactions for third parties, which is licensable. A commercial-agent exemption exists in several jurisdictions, but it is written for agents acting for one side only and supervisors read it narrowly.
Operators that would rather not hold the authorization take one of two routes: contract a provider that settles sellers directly, or run sellers as sub-merchants under a payment facilitator that carries the regulated role. Both cost control over timing and holds; how that choice shapes the money flow belongs to the marketplace itself.
DAC7, facilitator rules, and the fields you capture at signup
Two distinct tax burdens sit on operators. Reporting: platforms collect seller tax identifiers and report earnings to tax authorities, under DAC7 in the EU and equivalent regimes elsewhere. Collection: marketplace facilitator rules in the US and deemed-supplier rules for VAT in the EU and UK make the operator, not the seller, liable for tax on certain third-party sales.
Both depend on data captured before the first order. Retrofitting tax identifiers and establishment addresses onto a live seller base is a project measured in quarters, so treat it as tax compliance architecture rather than a finance clean-up.
Duties that attach to the listing
Prohibited and unsafe goods, counterfeits and inaccurate seller claims become the operator's problem once it has been notified, and increasingly before. Consumer rules on withdrawal periods, refunds and dispute handling frequently bind the platform alongside the seller, particularly where the buyer never dealt with the seller directly.
Checks that live in the product
Compliance written into a policy document and nowhere else fails at the first examination. It works when the software enforces it: payouts blocked until verification clears, funds held through the dispute window, listings gated by category, changes to payout details re-verified before they take effect. The vendor onboarding flow is where most of these controls physically sit.
What an examiner or an acquirer asks to see
Not the policy — the evidence. Screening logs, dated verification records, and the decisions to reject or offboard sellers with the name of whoever made them. A marketplace being sold or applying for a licence gets the same request, and diligence usually stalls on the same finding: controls that ran but were never recorded.