It is possible for new uses of known things to be ‘novel’ in the patent sense, (i.e. not known) where they are directed towards a new use that is sufficiently different so not to be regarded as being part of the state of the art.
Novelty in this sense is assessed by asking the question, “has the claimed functional feature previously been made available to the public?” In the Mobil Oil case, a compound previously used as a rust-preventing additive was successfully patented for the purpose of preventing friction. The friction reducing qualities of the compound were the functional technical feature and as the compound had only previously been known for rust-prevention, this use was novel. This approach was somewhat criticised in the case of Merrill Dow v Norton where it was held that the disclosure of a process made available to the public everything which inevitably took place as part of the process, whether appreciated or not. Here, the chemical reaction in the body produced by the ingestion of terfenadine had an anti-histamine effect. The invention was being worked before the priority date becuase the public were able to take terfenadine and by doing so, necessarily, they were working the invention disclosed in the new patent . Thus, the first patent claim contained enough information to render the new patent invalid. The Court held that there had been anticipation by use (in the liver) and anticipation by disclosure (in the patent claim). However, the Court did say that acts done secretly or without knowledge of the relevant facts, which would amount to infringements after the grant of a patent, would not count as anticipations before.