I am not a lawyer, but as Chair of the WSFS Mark Protection Committee (MPC), the entity that works to protect the intellectual property of the World Science Fiction Society, I've had to become conversant with issues having to do with trade and service marks. In light of a question I was recently asked (no, I won't say where), here are the symbols you can use to indicate that what you're using is a trademark or service mark, and whether the mark is registered with the appropriate authority or not. Much of this is cribbed from other sources, such as this one and the Wikipedia article on the subject.
( Trademark Neepery )
Something you don't need to do, and indeed really shouldn't do because it's silly, is to use one of the mark symbols on every single usage of the mark. You don't go around writing, say, Coca-Cola® every time you say you bought a Coke®, and not even the Coca-Cola Company would say that you should, as long as you're using the words to describe their actual beverage. Similarly, don't go around writing Hugo Award® and Worldcon℠ over and over just to be cute. But conversely, don't use the WSFS marks to describe something they aren't, and also, use the Hugo Award Usage Guidelines and the actual Hugo Award logo when you want to illustrate something that talks about the Hugo Awards. Don't use random images you can find by doing a Google Image Search on "Hugo Award" just because you personally like that design better. (Those images are from artists whose logo proposals were not selected by the MPC when we developed the logo, and in theory are there to allow those artists to display their work as exposure for them.) Using non-official Hugo Award logos actually hurts the Hugo Awards and Worldcon by eroding our intellectual property and creating confusion. So when it comes to writing about the Hugo Awards, accept no substitutes!
( Trademark Neepery )
Something you don't need to do, and indeed really shouldn't do because it's silly, is to use one of the mark symbols on every single usage of the mark. You don't go around writing, say, Coca-Cola® every time you say you bought a Coke®, and not even the Coca-Cola Company would say that you should, as long as you're using the words to describe their actual beverage. Similarly, don't go around writing Hugo Award® and Worldcon℠ over and over just to be cute. But conversely, don't use the WSFS marks to describe something they aren't, and also, use the Hugo Award Usage Guidelines and the actual Hugo Award logo when you want to illustrate something that talks about the Hugo Awards. Don't use random images you can find by doing a Google Image Search on "Hugo Award" just because you personally like that design better. (Those images are from artists whose logo proposals were not selected by the MPC when we developed the logo, and in theory are there to allow those artists to display their work as exposure for them.) Using non-official Hugo Award logos actually hurts the Hugo Awards and Worldcon by eroding our intellectual property and creating confusion. So when it comes to writing about the Hugo Awards, accept no substitutes!