If you own a brand and want to really protect it online, a basic action would require you to buy more than 250 domain names.
280 is indeed the number of domain extensions in total:
- 20 generic TLD (.com, .net, .biz, .edu … to name a few)
- 248 country code TLD (.fr, .de, .th, .us, .uk, .ru, .cm to name a few)
- 1 historic extension: .arpa
- 11 would be extensions currently in testing phase.
So to be sure that no one can buy you brand name online, you need to register 268 domains. And then you might need to consider some common typos and hyphen versions and key product names.
Have you done it yet?
This seems rather over the top and expensive. Of course there are going to be some that you will probably never need to register, and some have location and company requirements, so you will not be able to register them, reducing the number down somewhat.
At the end of the day you need to weigh up the risks involved if someone else registered your name in another extension. If you later change your mind and decide you do want that domain, the cost to recover such a domain will be far more than the original registration fee.
WIPO and UDRP costs are over $1500 to begin with, and if you include your time and legal costs you could be looking at closer to $5000 and even then you might not win.