Were sx At the same time with. . Bq for the Caribbean Netherlands, and. Cw introduced for Curaçao. The contracting authority is operated by the company SX Registry SA, in which it is a joint venture between Luxembourg and Canadian registrars Open Registry and Media merger. Domains under. Sx can be registered by anyone for any purpose, a residence on Sint Maarten is not required. The authority allows only alphanumeric characters and such an address with a length between three and 63 points.