Lets say you're an average joe and you own a site. The site gets bigger and bigger each month...when do you start thinking about trademarking your name? What if someone does it before you just because they know its not trademarked and they see that your site is huge and your name isnt trademarked? are you screwed then?
If you can show prior use you could at least avoid being tol dyou have to stop it - but doesn't mean you wont' get sued. If your company name is that important to you, spend the few hundred and trademark your name (and logo if applicable). You can file the application today and state the date of first use being the actual date you first used the mark in commerce (meaning, you used it publicly in trade). Go to the uspto(dot)gov website and look up info there, you should also search to make sure no one else has same name traemarked before you started using it!
haha if you're that worried about a trademark being taken why not get the trademark yourself?? start the process now, because it takes about 6 months.
The US recognizes common law trademarks - no Federal Registration is required to establish rights. First to use, continue to use, for that particular classification (there are over 40) has a first usage claim. Generic names for common usage are not able to be trademarked (i.e. Apple Pie for a baked good). If you had a hosting business called "BlueSnake" hosting - someone cannot run out and steal the name by filing for a trademark unless they used the name before you. It takes about 6 years for a Trademark to become uncontestable. Before you decide to file, the first thing you should do is establish that you were the first person to use the term for this usage (not just the web). You trademark the name/phrase (logo/image is much less strong), so if bluewidets.com is being used for hosting, you cannot file for a trademark on bluewidets.net. You could also not get a trademark on bluewidgetshosting.net or com. If your name passes that test, you should really get a trademark search done (a couple of hundred dollars) - it is a lot more complicated than just searching the USPTO. The majority of names will show prior usage rights. You can file for a trademark yourself, but if you make a single error, you lose you money and you need to refile. An attorney can do everything for a ballpark of about $1,000. You will need to have an attorney if someone comes forward during the next 6 years and claims they had prior rights to the name (contests you trademark filing).
What if you start a website with a trademarked name before trademark is official reg. But your not the first to use the name and you were unaware all about pending trademark?
You do not need an "official trademark" to have a trademark (no need to file anything). Federally Registered Trademarks are granted by classification, so in theory, you can have 40 different people with rights to a keyword (each have their own usage). If you start a website that infringes upon a trademark that is was in use before yours, you are guilty of infringement. It doesn't matter if you didn't know about it - you have an obligation to make sure no one else was using the trademark before you. Having a Federal Trademark makes it easier to take a domain from an infringer and also can provide for treble legal fees - but without a registered mark, they can still sue the person. As I stated, going to the USPTO.gov website and doing a search isn't enough. A good search runs several hundred dollars and checks business records, telephone books, official filings, etc. Even similar, phonetic, misspelled names can be trademark infringement and that is a lot harder to research on your own.