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Do not include www when adding a domain to your targeting list. If you want to target a specific subdomain like sports.domainname.com, it can be included on a targeting list. Note that a domain such as domainname.com/yahoo is not a valid domain for use in targeting lists. When targeting a subdomain, the rest of the domain is not targeted. For example, if you have whitelisted allowlisted the domain sports.domainname.com, a request from arts.domainname.com would not pass targeting.
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When applying a domain list, you will be prompted to select whether it is a Blacklist blocklist or a Whitelistallowlist. Use Blacklists blocklists to block any requests from select domains. Use Whitelists allowlists to allow requests from only the domains you specify.
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Account Domain Lists: Go to Settings → Basic Settings → Account Targeting → Account Domain Blacklistsblocklists
Campaign Domain Lists: Campaign→ Targeting → Domain Targeting
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You can associate a domain list on the Supply and Demand tabs of the domain list, or you can do it from the individual tag targeting tab. In the Supply and Demand tabs of the domain list, you will see a table containing your tags. The "+Supply" and "+Demand" buttons will display a menu to add as a whitelist allowlist or a blacklistblocklist. Selecting one of these options will display a modal of your tags and you can select the ones that should target this list. Note that you can apply unlimited domain lists of the same type to a single tag.
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