I'm afraid you're wrong. "Comprise" in a patent does not mean "all, no more and no less". See, eg http://www.patentlens.net/daisy/patentlens/202.html http://ww

I'm afraid you're wrong. "Comprise" in a patent does not mean "all, no more and no less". See, eg http://www.patentlens.net/daisy/patentlens/202.html http://www.patentlens.net/daisy/patentlens/202.html The transition words or phrases commonly used are "comprising," "consisting of" and "consisting essentially of" and have very distinct meanings: "Comprising" is open-ended language, meaning that the claim encompasses all the elements listed but does not exclude additional, unnamed elements. For example, if a claim recites elements "A" and "B", an individual that practices the invention using elements "A" and "B" is infringing, and using "A", "B", and a new element "C" is infringing, whereas if she only uses element "A" or "B", she is not infringing. In contrast, the transitions "consisting of" and "consisting essentially of " have more limited scope. "Consisting of" means that the device (or method) has the recited elements (or steps) and no more. For example, if a claim recites " A" and "B" and the individual uses only "A", or "A" and "C" but not "B", or even "A", "B", and "C", the claim is not infringed. The meaning of "consisting essentially of" is intermediate to comprising and consisting of. A claim using this transition includes additional elements only if they do not affect the basic and novel characteristics of the claim. " Consisting essentially of" is not often used. Drafting a claim to use open-ended language will enable the patent to be as broad as possible. Narrowing the claims to be more specific is the kind of thing that a patent examiner might demand in order to approve the patent. (And this is why you have to employ lawyers whenever patents are involved, as otherwise your opponents will rip you to pieces in court.)