The Case of the Curious Trademark. Universal has applied to register the SHERLOCK HOMEBOY trademark but the estate of the creator of Sherlock Holmes may have something to say about that.
Beginning in the 1880’s, Sir Arthur Conan Doyle authored and published four novels and 56 short stories about the exploits of detective Sherlock Holmes and his trusted sidekick, Dr. John H. Watson. Most of the stories are now in the public domain and this is why there are so many Sherlock related television shows and movies….cause it is free to exploit. The Doyle Estate unsuccessfully tried to claim that some of the stories were not in the public domain in a dispute that went all the way up to the Supreme Court and you can read about that here. While the stories are in the public domain, the SHERLOCK HOLMES trademark is still owned, and enforced by, the Doyle Estate. Recently, the Estate fought over the registration of the Sherlock Gnomes trademark.
The “Sherlock Homeboy” term has been used by many different people and companies but has its origin in a television show reference. Way back in 1990, NBC premiered a sitcom about a kid from Philadelphia being sent to California to live with his rich family in a show called, *The Fresh Prince of Bel-Air. *The show starred an up-and-coming rapper named Will Smith and the show lasted for six seasons. During an episode, Will eavesdrops on a conversation between his cousin Hillary and her friend and overhears that Hillary has dropped out of college but hasn’t told her parents.  Will pulls out a magnifying glass and says: “This is a job for Sherlock Homeboy.” (Picture for your reference.) Sherlock Homeboy was later used in a series of YouTube videos about an inner city detective, again as a band name, and even on the kid’s television show, Yo Gabba Gabba. So it seems the name caught on. 
Back in 2006, Universal tried to register the trademark for the SHERLOCK HOMEBOY term and it was initially approved by the Trademark Office without an opposition from the Doyle Estate but Universal never submitted proof that the mark was actually in use, so the attempted registration was abandoned. In April 2015, Universal once again filed registrations to use the mark on a series of goods covering television programs and a whole bunch of merchandise like t-shirts.
Yesterday, the Doyle Estate filed an application for an extension of time to oppose the mark. This is the usual first step that allows the parties time to resolve the dispute or gives the potential opposer more time to decide if it wants to oppose the mark. Doyle would need to prove that the SHERLOCK HOMEBOY mark is confusing similar to its SHERLOCK HOLMES mark. Seems like the potential mark is just a parody but just because a mark is a parody does not justify it being registered as a trademark; parody is merely a defense to claims of infringement. Universal walked away from this registration before and it might do so again if they cannot resolve the dispute.