QuoteDistinguishing between the look and the function of an invention isn't always easy. But imagine that you're seeking a patent for a wine glass. If it's simply a combination of glass stem and bowl that has been done many times before, it would not be eligible for a patent. But if there is some sort of unique, fanciful etching on the glass, then it could theoretically be patented if that design feature is "inseparable from the article to which it is applied and cannot exist alone." The question of what makes a patent too obvious to merit protection, which the U.S. Supreme Court is currently mulling, applies to design patents as well as utility patents. The distinction with design patents is perhaps even more fuzzy, said Philip Mann, a Seattle-based patent attorney and author of the IP Litigation Blog.