If you are not familiar with the Angry Birds logo and game by now, then you have been living under a rock for the last few years. Indeed, Rovio's Angry Birds trademark and logo is well-recognized (I admit to having spent countless hours playing Angry Birds). One of the many trademarks owned by Rovio is this little angry guy:
Note the eyebrows, the scowl (if birds could scowl, that would be what it looks like), and the angry eyes. Now, consider this trademark from a company who makes golf clubs that apparently doubles as a swing trainer and equipment saver:
Again, note the angry eyebrows and eyes, the red color of the "A," and the scowl. Look familiar? It should. Indeed, in the video promoting the Angry Club, the owner discusses killing "two birds with one stone." Huh, maybe he is trying to evoke a certain angry Ave? The idea is that the Angry Club works as a swing trainer to allow you to warm up before hitting the golf course. Then, once on the golf course when you hit a bad shot, instead of damaging your equipment (e.g. breaking your club over your knee or throwing your bag into the water), you just slam the Angry club on the ground and it angrily berates your play.
Needless to say, Rovio did not take too kindly to Indiegogo (the Angry Club company) using a trademark that evoked their beloved (and valuable) trademark. Yes, you guessed it, they sued. After all, Rovio could not have these duffers turned inventors diluting the value of their Angry Bird marks. Ultimately, the lawsuit resolved by settlement wherein Indiegogo agreed not to use the name "Angry Clubs" or the "A" logo.
This case illustrates the importance of being careful about how you go about choosing your trademark. Now, after spending time and effort promoting the "Angry Club" name and using the "A" logo, Indiegogo is back to square one with regard to marketing its brand--it must now come up with another one which will not infringe upon or dilute another's intellectual property.
My guess is that the inventor did not consult with a trademark attorney before deciding on the name and the logo for his golf swing trainer. Had he done so, he probably would have avoided the lawsuit altogether. Yes, attorneys are not necessarily cheap, but hiring an attorney at the front end usually saves you money by not having to hire one once litigation or a dispute arises.