It simply means only one person is allowed to use a specific domain name. Once a person registers a domain name related to the trademark, then any other person will be denied registering a domain name related to that trademark. Other applications for registering the same domain name will be rejected; otherwise, it will cause a domain name dispute if the trademark owner doesn’t register a related domain. If you are running a business, you might want to use your trademark as your domain name. If not, you need to think about the costs and other possible outcomes of any dispute resolution procedure or court case.
If someone is already using your trademark as a domain, you can dispute the right of the person to use it. You can challenge the use of the domain name by filing for arbitration or filing a civil lawsuit. Alternatively, you can offer the person to buy the name and skip the hassle of disputing the ownership.
When a large, well-funded company files a case, small businesses often decide that their best course of action is to admit a disputed domain name and negotiate appropriate settlement terms.
On the other hand, if you have crucially invested in building your business reputation, then this may not be a satisfactory result, and you’ll have a strong case for defending a claim.