Trademarked Domains
Some domain names are protected by trademarks registered in the Trademark Clearinghouse (TMCH). When you attempt to register one of these domains, the registry requires you to acknowledge a claims notice before the registration can proceed.
How it works
The TMCH is a centralized database of verified trademarks, mandated by ICANN for all new generic TLDs (gTLDs). During a TLD's claims period — typically the first 90 days after general availability — any registration attempt for a domain matching a registered trademark triggers a claims notice.
Claims periods are set by each TLD's registry. Some TLDs extend claims indefinitely. Check the TLD specifications for details on a specific TLD's policies.
Identifying trademarked domains
When you check domain availability with GET /v1/domains/check, a trademarked
domain returns a claims_key:
{
"results": [
{
"domain": "brandname.shop",
"available": true,
"reason": null,
"is_premium": false,
"claims_key": "claims_key_from_check_response"
}
]
}
The claims_key field means the domain is available for registration, but
trademark claims must be acknowledged first. Submit the same value as
claims_notice_acceptance_hash after the registrant has accepted the notice.
curl --get "$OPUSDNS_API_BASE/v1/domains/check" \
--header "X-Api-Key: $OPUSDNS_API_KEY" \
--data-urlencode "domains=brandname.shop"
Registration workflow
Registering a trademarked domain requires three steps beyond a normal registration:
1. Detect the claims requirement
After the availability check returns a non-null claims_key, keep that value.
You need it when submitting the registration.
2. Present the notice to the registrant
ICANN policy requires that the claims notice is presented to the registrant in full and that the registrant explicitly acknowledges it before you proceed. Programmatically accepting notices without genuine registrant acknowledgment violates ICANN's Registrar Accreditation Agreement.
The registrant must review the trademark information and confirm they understand that:
- The domain they are registering matches a registered trademark.
- They have a legitimate right or interest in the domain name.
- They are not registering the domain in bad faith.
3. Submit the registration with the acceptance hash
Once the registrant has acknowledged the notice, include the returned
claims_key as claims_notice_acceptance_hash in your registration request:
curl "$OPUSDNS_API_BASE/v1/domains" \
--request POST \
--header "X-Api-Key: $OPUSDNS_API_KEY" \
--header "Content-Type: application/json" \
--data '{
"name": "brandname.shop",
"contacts": {
"registrant": "contact_01h45ytscbebyvny4gc8cr8ma2"
},
"renewal_mode": "renew",
"period": { "unit": "y", "value": 1 },
"claims_notice_acceptance_hash": "claims_key_from_check_response"
}'
Claims notice acceptance hashes expire. If the hash has expired when you submit the registration, the request will be rejected and you must run the availability check again to receive a fresh claims key.
Bulk registration with TMCH
When using the Jobs API for bulk domain
registration, you can include the claims_notice_acceptance_hash per instance:
{
"command": "domain_create_bulk",
"payload": {
"template": {
"contacts": {
"registrant": "contact_01h45ytscbebyvny4gc8cr8ma2"
},
"renewal_mode": "renew",
"period": { "unit": "y", "value": 1 }
},
"instances": [
{
"name": "brand-one.shop",
"claims_notice_acceptance_hash": "claims_key_for_brand_one"
},
{
"name": "brand-two.store",
"claims_notice_acceptance_hash": "claims_key_for_brand_two"
}
]
}
}
Related guides
- Register a domain — full registration workflow
- Premium domains — handling premium-priced names
- TLD specifications — TLD policies and phases
- Jobs: Domain commands — bulk registration
