fine spoke the center on the edge of the sky usually behind sheetrock in a wall it does this by measuring and comparing capacitance that's the electrical charge of two separate conductive plates to locate the stud hiding behind the  wall the most technical definition of that is in column for the specification the issue before this court is whether the term right show is used throughout the n i one patent means either a result of dividing two values that's what stanley urges and that's what the skeins that are specifically comparing a division or using division to compare is opposed to using subtraction to compare division exist in this pattern is one method but so does subtraction so don't look up ta talking about division exactly either if i can work from the claim and work backwards it might make more sense if you start with twenty one is the example and in our brief at page sixteen we started talking about claim twenty determined range if you put zircons definition in there and you say determining the relation in degree or number between the first and second capacitances determining whether the relation is within a pre determined range then claim nineteen which depends on ten then gives you another limitation in clay nineteen it says the determination of the relation between the first and second capacitances comprising comparing so the way we're going to compute the ratio which has to be the broadest term because it's in claim ten that everything else is it talks about the specification discloses a comparison circuit made computer ratio so you have to start way up that line fifty in there it talks about computing or a show and it's going to be very similar to what i just read you between claim ten one thousand and twenty one column fourteen i'm up at fourteen if you start at forty nine for example the comparison circuit may computer ratio between the passive measurements we're talking about this if you go up if they were describing figure twelve gray and column fourteen it starts by the comparison circuit make computer ratio the next paragraph so now i'm jumping down the fifty six the comparison circuit that was just discussed is to make computer ratio may compare and or process the capacitance measurements capacitance measurements may be considered equal when they are within a pre determined percentage value or absolute value from each other so what i'm saying is computer ratio is not used to record with this in this case i think there's more than one plain meaning of the term and we both i don't never tried my kids math and i can't do that either if you look at the dictionary there's a definition that makes sense in this context and it's a broader definition and it's not the narrower mathematical definition it's one that really means you take the relation and when i sit and look at these claims and i look at claim twenty one claims sixteen is the same it talks about computing a ratio in taking it doesn't actually say taking the difference but it says computer a show and compare capacitance to find the greater of the two in those instances particularly the want to just walk you through with claim twenty one it just doesn't make sense if computer ratio itself means to bot if that means a proportion in every instance those things don't work together but it does if you take the dictionary definition that says the relation between the two and that's what i was trying to walk through with the quiet in the specification i think we'll get you there the same way that when we were just reading for instance always depended on nineteen if you look carefully at the two at what is now claimed nineteen which is the kind that was then depended on flame one what was different between it and original claim one was that it actually had a narrowing limitation in the cup if i can put it to you it has a narrowing limitation that didn't exist in claim one in that is that the two plates have to be approximately equal so it made sense and it was consistent to make that depend on plain one because claim one was always broader the only difference between claim one and what original claim one and what is now claim twenty one was really that the two were approximately equal which is a limitation that's why it was changed never in the prosecution history never did the term computing a ratio change did the claims that depend i mean the dependent claims in the structure between claim twenty one what's now claim twenty one and twenty two none of that change back quickly to specification we all can see that the specification discloses subtraction my point is that the element of computing a ratio is a different element than comparing the capacit sense if you use our definition and computing a ratio is the relation between the two and the way i read nineteen in the difference with nineteen is it's a broader claim obviously than twenty one or twenty two and it's comparing claim twenty compare and i think the point there was that you're detecting an edge and that's the difference between playing ten but i also if you look at and compare this with say for example column seven and specifications line twenty seven through thirty four and then again it nineteen lines thirty through thirty three there there's a description of comparing capacitance measurements and finding the center of the stud when the measurements are equal or alternatively approximately equal to unity and we know that approximately equal to unity is division so equal should mean something different and it's those are consistent with kind of what i've been trying to map out that i think is consistent with the transition between claim ten claim nineteen and claim twenty one in this context it's the same thing you're talking about computing a ratio is a very broad concept and then you talk about different methods of doing that and within that context there's always different ways to get there one is division one is subtraction so for computing a ratio to mean division itself it doesn't work in the context of the claim or the specification or the prosecution histories now just one more example if you take the examples that stanley cited in their briefing from the specification where they say ratio means division that's not what the spec is saying the spec in each instance is saying maybe can the ratio may be computed and it may be computed by division so if a ratio may or may computer ratio by dividing it right show means division there would be no reason to spell out those extra steps and explain it on behalf of the stanley works now known as stanley black and decker as is fairly clear with this case there's really no dispute a lot but a lot of issues this division scrubbers a racial word ratio in the uncommon man of the little dictionary definition that a lot of daylight well first of all just the two dictionary definitions we're dealing here with the prop as a processor in a circuit that computes an algorithm so it makes sense to fault the mathematical definition which is exactly what the district court said as to the other issue if they're going to use a smaller special or a more fas definition their duty is to have a manifest definition to be their own lexicographer if they want to vary ratio to mean something specification we use the mathematical definition we use a number of extrinsic evidence treatises explaining an expert electrical engineering definitions to show how it's used in the circuit context and it's always used in the context call fourteen of the patent sure down on line forty nine for example it exactly it may computer ratio between the capacitive measurements that's one alternative  they may determine whether the capacitive measurements are within a pre determined value of each other that's a second alternative nowhere does that equate computing a ratio with the subtraction operations in fact if you go down to the very bottom kill it capacitive its measurements an element light sixty four may be considered equal when they're within a pre determined percentage value in a percentage is a ratio of percentages basically dividing one besides the the inside the other and here's the keyword as or your absolute value from each other that subtraction they don't equate them they actually say they're different they say there are alternatives they use the word or on the next flipping over to call them nineteen at line twenty eight end instead of the line thirty that is if the capacitance ratio is approximately equal to unity again we're talking about ratio division or alternatively if the capacitance measurements are approximately equal to one another which i believe is subtraction again we use the word the zircon use the word alternatively that is the disjunctive that is saying these are different it's saying that ratio is not to the other thing the specification actually compels that ratio cannot cover subtraction and now they're trying to say that the disclosure of code with equal equates and that's that's what a wrong because the specification itself undercuts that the prosecution history does the same thing they started out with to be perfectly honest  great claim that said comparing the claim broadly covered all forms of comparing then they got the search report and they filed an amendment saying was cited in an information disclosure statement without much more explanation than that and they surrendered that claim they basically took claim and subordinated it to claims that coverage ratio anyone reading that prosecution history understands they gave up a strongly broad coverage instead of a claim that had extremely narrow coverage or disclosed a reference that had and it was labeled as an x which means it's interest of the tory it did actually have well this is we're straying outside the record was not a disputed point i do know what senate it had an equation going to be perfectly honest i think i wrote it back that had  some component of subtraction in the comparison and then it was good to be honest we didn't really litigate this issue below but i do know what was in it so i don't really want to straight i want to answer the question i don't want to stray too much on that because that's really not part of the record here  but the fact of the matter is it really doesn't matter because under the law this court the obligations and on is on circuit on to prove that was not related to patent ability we don't have to as stanley explained why the amendment was made or not the presumption is on make the explanation and act i could sit here in pure silence and say nothing in that obligation would be on them to explain why it was made that's how the prosecution history  business somewhat of a deep pendant claim argument the way big claim was drafted here it's really a fall of the prosecution history they gave up all forms of comparing i'm not really entirely sure how to explain what claim why claim twenty one is what it is but the way it should be read in accordance with section one twelve paragraph four is that it adds a further limitation it adds a subtraction operation in addition to the computing a ratio operation doesn't change the definition of ratio and in fact if you were to use it to change the definition of ratio in order to import any consistency between those two claims you create in consistency across many many other claims because they include a lower boundary on a range result that's a problem for a circuit not the rest of the public but the plane it actually is not very it's not unintelligible when you think about it you can have a device that divides and subtracts for whatever reason a fall back a redundancy they they can more accurate precise whatever reason it would they would like to do it the claim actually is technically a sound claim understand this interpretation and would ratio interpretation issue really everything in this case falls back into place the disclosure dedication rule circuit doesn't dispute the subtraction disclosed and nobody disputes that's the operation the stanley uses in its device prosecution history stopper falls into place because ratio can't be the same as comparing that was a change in narrowing in scope unless there anymore questions i'm prepared to wrap my argument  established today that it's our position that that's a separate element from the methodology used to compare the capacitance and i think if you look at column fourteen it showing you computer ratio encompasses both proportionate value and absolute value in it's contemplating that that broader computer ratio step is going to contemplate different methods through comparison or over whatever other steps are in that including look up tables in the claims if you go to the claims and you look at the claims where there's a numeric range say for instance claim seventeen it depends on ten and then it gives you a range which results in point nine to one in that instance computing a ratio under our definition would make sense because you're in the broadest sense finding the relationship and then claim seventeen it's not the dependent back on clean ten that tells you to divide it's the fact that the range results and point nine to one which we've all established requires division to get there a proportion of some sort be the same thing with playing twenty three for instance there are a sensor generating a ratio of approximately one in those instances it's that second step that second element independent from computer a show that's telling you to divide and that's the way you construe this claims the specification in the prosecution history so that they are consistent and they harmonize this is not a case where you have to rewrite the patent for it to make sense this is a case where you only have to rewrite the patent for it to make sense if you adopt stanley's construction there is a dictionary definition that works here it's just not the wants just real quickly on the amendment the burden doesn't ship to us and there's no prosecution history a stock ball unless we actually gave up something unless there's a limitation there something we've surrendered and walking through what i see as the change in those claims i don't see that we gave up anything we're talking about today we didn't give up there is a dedication