When cobwebs and tombstones start to show up in your neighborhood, probably something wicked is coming your way—except that one night of the year, on Halloween. Even though Halloween involves frightening things—haunted houses, the undead, tricks in response to no treats—it is ultimately about carefree fun. And there’s candy! But if you are in a Halloween-related business, there is a genuinely scary side to the holiday—IP issues that, if ignored, could lead to a wicked lawsuit.

For example, in 2005, in the case Chosun International, Inc. v. Chrisha Creations, Ltd., the US Court of Appeals for the Second Circuit declared that elements of a (not very scary) Halloween costume could be copyrightable. Under the US Copyright Act, protection does not, in principle, extend to utilitarian or functional elements of the artist’s original work and, therefore, does not extend to elements that enhance a costume’s functionality qua clothing. However, in the case of Chosun’s plush sculpted animal costumes, the court held that certain elements might be separable from the overall design of the costume, and hence eligible for copyright protection. For example, Chosun might be able to show that the sculpted “heads” and “hands” of its costume design are physically separable from the overall costume in that they could be removed from the costume “without adversely impacting the wearer’s ability to cover his or her body.”

Thinking of creating a costume based on something less cuddly—say a fictional serial killer, such as Michael Myers, Hannibal Lecter or Dexter Morgan? Think again. In principle, fictional characters within an original work of authorship (e.g. a book or a movie) are presumed to be simply ideas not worthy of copyright protection on their own. However, fictional characters may be protected independently of their underlying works, provided that they are sufficiently unique and distinctive. In US law, the consensus seems to be that a well-defined serial killer may be copyrightable. Perhaps the most famous comment on the copyrightability of fictional characters comes from Second Circuit Judge Learned Hand in the 1930 case of Nichols v. Universal Pictures Corp. where he wrote that “the less developed the characters, the less they can be copyrighted; that is the penalty an author must bear for marking them too indistinctly.”

Happy Halloween!

Finally, you have to be mindful that many trademarks include the term “Halloween” in their mark. And there is a significant number of patent applications relating to Halloween-ish things like coffins, pumpkins or even, in PCs, “zombie process detection.”