Category protection
We exclude businesses in your selling categories and the categories and businesses you block.
Every one of your categories counts
A business is excluded when any of its categories matches any of yours, not just a primary category. A seller with several websites is treated as one business group.
Example
A fictional host sells in Coins & Bullion and Collectibles & Comics. A fictional candidate sells in Collectibles & Comics and Home & Living. They share Collectibles & Comics, so the candidate is excluded even though Home & Living does not overlap.
Your blocks
You can block a business or a domain. A block applies in both directions, so the blocked business also never shows your box on its own site.
Related categories
NOSA can mark pairs of different categories as conflicting where products overlap. A reviewed list has not been published yet, so today protection is based on matching categories and your blocks.
Unclassified businesses
A business whose classification is missing, unmapped or "Other" is not shown until it has been reviewed.
Limits of the approach
Category labels cannot identify every possible competitor. Use blocks for businesses you do not want shown, and report a category mismatch if you see one.