Warner Bros owns many trademark registrations for the "The Hangover" mark.Therefore,they contended that the disputed domain name is confusingly similar with its trademark.Moreover,they contended that the respondent registered and used the disputed domain name in bad faith:
"Respondent collects click-through fees each time one of the links on its site is accessed. In this way, Respondent is realizing a commercial gain from the operation of its site. Additionally, Respondent’s operation of the website at a domain name which bears a confusing similarity to Complainant’s mark is evidence that Respondent is seeking to benefit from the confusion created by the confusing similarity."
The Panel ordered the disputed domain name be transferred from respondent to the complainant.
You can read the decision here .



