Someone else has used my registered trademark (or company name) as a domain name. What are my rights?
Contact a lawyer. All ICANN-accredited registrars follow a uniform dispute resolution policy, under which disputes over entitlement to a domain name are ordinarily resolved by court litigation between the parties claiming rights to the registration. The registrar will uphold the findings of the court. In disputes arising from registrations allegedly made abusively (such as “cybersquatting” and cyberpiracy”), the uniform policy provides an expedited administrative procedure to allow the dispute to be resolved without the cost and delays often encountered in court litigation. For more details on the uniform dispute resolution policy, please visit the Uniform Domain-Name Dispute-Resolution Policy at ICANN. In any event, do not act on your own. Consult with a lawyer before anything else.