Apple\'s heavy-weight patent dispute with Korean electronics giant Samsung lacks a silver bullet, an industry analyst said. \"There is not single killer patent in this lawsuit,\" said Florian Mueller, who studies and writes about patents. \"Apple cannot deal a knockout blow to Samsung.\" A cornerstone to the case could be a \"universal interface\" patent owned by Apple that was the catalyst for Judge Lucy Koh\'s injunction in June ordering Samsung to cease U.S. sales of the Galaxy Nexus smartphone. That alone shows the potential power of a patent battle. Despite the image of legal gladiators clanging about in a courtroom in a war of words, patent disputes can steer investors toward one company or another. The \"universal interface,\" The New York Times reported, is a jargon-oriented description of a question-answering application called Siri, which Apple bought in 2010. Nevertheless, a smartphone is a complicated devise, so much so patent licensing firm RPX estimated 250,000 patents are associated with each phone. A recent patent case in Chicago between Apple and Motorola Mobility, which is owned by Google, was tossed out by federal appeals Judge Richard Posner. The two were suing and counter-suing over broad-sweeping accusations. Posner declared a \"pox on both of your houses,\" scoffing at the legal frothing.