This is general information, not legal advice. If you are running significant sponsorship revenue, have a lawyer look at your setup.
The rule, in one line
If money changed hands, the audience must be able to tell — clearly, and before the content influences them.
The FTC's Endorsement Guides cover this in the US. The principle is materially the same in the UK under CAP rules and across most of the EU.
What "clear and conspicuous" means
The FTC has been specific about this, largely because so many people got it wrong:
Visible without hunting. Above the content, not below it. Not requiring a scroll or a click to reveal.
Plain language. "Sponsored", "Advertisement", "Paid partnership". Not "Spon", not "collab", not "#ad" buried in a list of twenty hashtags.
Same medium. A label on a video should be in the video, not only in the description.
Unavoidable. If a reasonable person could consume the content without noticing the label, it is not conspicuous.
Display advertising
A banner in an obvious ad slot is generally understood as advertising, but labelling is still the safer practice — and it matters more the more your ad looks like your content.
- A 300×250 image banner in a sidebar: low risk, label anyway
- A text or native placement styled like your content: label, always — this is exactly the case the rules exist for
The label belongs on the slot, not the creative, so it appears regardless of which advertiser is running. A publisher who lets each advertiser supply their own disclosure will eventually run one that has none.
"Sponsored Advertisement" or simply "Advertisement", small, above the unit, is sufficient and standard.
Sponsored posts
Higher stakes, because the content itself is the advertising.
- A clear label at the very top, before the first paragraph
- In the same typeface and size as your body text, not shrunk into invisibility
- Naming the sponsor: "Sponsored by Acme" beats a bare "Sponsored"
If the post appears in an RSS feed or a newsletter, the label has to travel with it.
Affiliate links
Also covered. If you earn a commission, say so. A line at the top of the post — "This post contains affiliate links, which means I may earn a commission" — is the usual approach and is generally sufficient.
Who is liable
Both parties can be. The advertiser is responsible for what is claimed on their behalf, and the publisher is responsible for disclosing the relationship. "The sponsor said it was fine" is not a defence.
The practical setup
Three things, and you are in reasonable shape:
- A label on every paid placement, set at the slot level so it cannot be forgotten
- A clear label at the top of every sponsored post
- A short line on your advertise page saying you label all paid placements — which, usefully, also signals to sponsors that you are professional about this