It's ironic that the "Open Source" name did not lead to clarity.

[Trevor Smith]

On January 5, 2004 1:43 am, J.B. Nicholson-Owens wrote:
> And I am not aware that the term "Open Source" was ever successfully
> trademarked.

Trademark law, at least in most industrialized countries that I'm aware of, 
states that any term used to publicly identify or differentiate a product or 
service in a market is automatically the trademark of the first user. Just 
like copyright does not need "registration" to exist, neither does a 
trademark. Anyone using a trademark can legally add a "TM" in a circle to 
their phrase or icon or whatever BUT they are NOT required to do so to make 
it a trademark. No one is required to register a trademark to make it a 
trademark but if they choose to do so (in order to document their use of it 
to fight future potential trademark violations, for example) then they can 
use the "R" in a circle "registered trademark" symbol.

That's how I understand the law anyway.

So, if the term "Open Source" was first used by an organization that wants to 
defend its use/ownership of the term, they probably have rights to it. Of 
course, law in North America favours those who have the money to enforce it.