Are there any official sites that allow me to search for a name and check whether it has been legally trademarked? Preferably including registrations from around the world, not just the US for example? Also, while I'm here... if a two-worded name such as "Aqua Men" was registered, would that also preclude the use of "Aquamen"? I'm not talking about domain names, just brands or names in general. Thanks.
You can search US trademarks at http://www.uspto.gov/main/profiles/acadres.htm Each country will have its own site In your aquaman example: A search at uspto shows that aquaman has been trademarked for swimsuits, action figures (cartoon/animation,tv,movies), fragrances and cosmetics, comic books, underwater diving services, and toy dolls. You woudl be able to use aquaman for non-competing uses - uses not in those categories.
In your example of a two word v single word version of the same phonetic grouping, you would not be able to use the single word version in categories where the two word version was already in use. So, if Aqua Men was used for clothing, you could not use Aquamen for clothing. You could use it for ice cream, however (assuming it was not in use for foods already). Trademark law covers phonetic variants, misspellings, as well as exact marks.
Both very helpful replies, thank you. If anyone has links to other countries' "versions" of that USPTO.gov site, or if there's an existing directory of them somewhere, that would be much appreciated also.
There is this, which will allow you to search through the trademarks registered through the Madrid Protocol (international ip). Here are some of the individual countries/regions.
The US recognizes common law trademarks, so there is no registration required to have legal rights to a mark. A good trademark search will run several hundred dollars and still not be a 100% guarantee.
It's a useful starting point for sure, but I wouldn't take it as proof that a name is legally available to use. Even if every brand in the world had an Internet presence, unless you do some fine filtering on the results, you won't get a reliable view of which uses the name has been applied to.