Monday, May 17, 2010

Inconsistent use of claim terms in specification

Takeaway: Is there ever a good reason to use claim terms inconsistently in the spec? For example, to say "power" when you mean "voltage"? I'm not sure the drafter/prosecutor of the patent in today's district court case planned it that way, but this inconsistent usage gave the patentee a chance at claims that read on the accused infringer when a straightforward reading would probably fail.

Details:
Symbol Technologies, Inc. v. Janam Tech. LLC
605 F.Supp.2d 618 (D.Del. 2009)
Civil Action No. 08-340-JJF

The claim term at issue was "power." The method claim recited:
7. A method for facilitating power shutdown protocol of a computing device, comprising the steps of:
... using a seconary cell as a backup portable power supply;
using a boost circuit to increase the power of the secondary cell ...

In the field of electronics, "power" is a term of art, with a specific meaning: voltage multiplied by current. The accused infringer advocated for this construction, but the patentee wanted a more informal definition of power: voltage.  According to the patentee, a POSITA would understand that the inventors intended for "power" to mean "voltage" because the specification did not explicitly adopt the ordinary meaning, and the specification also used the two terms loosely and interchangeably.

A magistrate judge originally assigned to do claim construction adopted the patentee's interpretation. But when the accused infringer objected, the court reversed and adopted the plain and ordinary meaning to a POSITA: voltage multiplied by current.

The court found that the spec neither explicitly adopted nor explicitly rejected the ordinary meaning, and the patentee's own expert admitted that some portions of the spec did use the ordinary meaning. The court also rejected the idea that "power" and "voltage" were used interchangeably in the spec. As support for this argument, the patentee pointed to various passages that described the power supply circuit solely in terms of volts (e.g., "5 volt power supply circuit"). But the court found that other portions of the spec clarified this usage by describing the circuit in terms of a combination of power and voltage (e.g. "steady 5 volt DC [direct current] power"). Thus, the spec when read as a whole consistently referred to the circuit's power output as a combination of both voltage and current.

My two cents: Is there something to be said for using terms inconsistently in your spec? Perhaps if you do this creatively and carefully, it gives you more options later in arguing claim construction. It didn't help the patentee in this case, but that alone doesn't make it a bad idea. After all, the patentee did convince the magistrate judge, and it's entirely possible that a different district court judge would have agreed.

As a patent prosecutor rather than litigator, I'm inclined to be consistent rather than inconsistent. When I'm drafting a spec and find that inventors have used terms inconsistently, I try to figure out what the inventors really meant in each instance, then I make my usage consistent. But perhaps a litigator would prefer a spec that was somewhat inconsistent and thus gave more leeway in claim construction. I'm guessing the patentee here wouldn't have had a case of infringement at all under the ordinary meaning of power, and that's why the patentee came up with this creative line of argument.

I haven't fully thought through this, so I'm not ready to advocate for intentional inconsistency in how claim terms are used in the spec. But I do think it's a valuable exercise to occasionally take off the prosecutor hat and put on the litigator hat.

9 comments:

  1. There is never a good excuse to confuse, or use interchangeably, power and voltage unless you are legitimately an idiot.

    As to your other question, be purposefully inconsistent at your own peril and to your own disadvantage at the PTO. 112, nuff said.

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  2. >never a good excuse to confuse, or use
    >interchangeably, power and voltage unless
    >you are legitimately an idiot.

    Ah, sounds like you're of the opinion that the patent drafter missed the boat, rather than made a deliberate decision to be artfully inconsistent. Guess we'll never know.

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  3. >112, nuff said.

    Really? I think inconsistency could help during amendments -- you have multiple words to choose from in your amendment rather than one.

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  4. "Really? I think inconsistency could help during amendments -- you have multiple words to choose from in your amendment rather than one. "

    Sorry, 112 2nd paragraph. Now, nuff said. MiyaMiyaMiya wa? Ex Parte Miyazaki, that's what.

    "Ah, sounds like you're of the opinion that the patent drafter missed the boat, rather than made a deliberate decision to be artfully inconsistent. Guess we'll never know. "

    Actually, from what I can tell, the patent drafter himself did not miss the boat.

    See here:

    "The court also rejected the idea that "power" and "voltage" were used interchangeably in the spec."

    That's because the drafter, who was likely not a mor on, did not use the two terms interchaneably.

    For instance:

    "As support for this argument, the patentee pointed to various passages that described the power supply circuit solely in terms of volts (e.g., "5 volt power supply circuit"). "

    That snippet from the spec is not improper or informal at all, a "5 volt power supply circuit" is fine to describe what a circuit is and it certainly isn't trying to redefine what power is to include voltage. What the phrase means is that the circuit provides 5 volts, regardless of what load you have attached (within reasonable limits of course) at a variable undefined current (dependent upon the load resistance/impedence) to provide power. It is most certainly not describing power in terms of volts.

    The court shouldn't even need:

    "But the court found that other portions of the spec clarified this usage by describing the circuit in terms of a combination of power and voltage (e.g. "steady 5 volt DC [direct current] power")."

    ^that because it is extraneous. But it does seal the coffin that the claim construction was already buried in with a few thousand nails.

    Thus, it was the litigators/patentee trying to make an issue out of this missed the boat because they are re tards. Likely what you should have said here:

    "According to the patentee, a POSITA would understand that the inventors intended for "power" to mean "voltage" because the specification did not explicitly adopt the ordinary meaning,"

    was:

    "According to the patentee's LITIGATION attorney, a POSITA would understand that the inventors intended for "power" to mean "voltage" because the specification did not explicitly adopt the ordinary meaning"

    Power always means the same thing.

    http://en.wikipedia.org/wiki/Power_(physics)#Instantaneous_electrical_power

    The definition, or meaning, of "power" has zip to do with I times V, even in the electrical arts. However, at the same time, it just so happens that I times V is one way of determining the power. Both of the attorneys in this case argued in a lame fashion. The attorney arguing against the "voltage" reading should have merely cited what "power" actually means, in all arts, at all times, rather than giving the lame V times I.

    Power when being used in the context of energy of some kind is always "the rate at which work is performed or energy is converted" or something meaning the same thing as that. "Voltage" aka "potential energy" doesn't even come close to that, in any, informal or otherwise, context.

    This is what happens when you sign up someone from either the bottom of the physics/EE class, or someone who was a civil/mech/chem/comp sci E person to handle your litigation. They don't understand what the terms they're using actually mean. Why? Because they never bothered to learn in the first place because nobody made them.

    We run into these types of issues every other week in my art.

    Either that, or the litigation attorney was trying to be tricksey and pull one over on the court. But we'll set aside as incompetence what would otherwise be assumed to be maliciousness k?

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  5. "Really? I think inconsistency could help during amendments -- you have multiple words to choose from in your amendment rather than one. "

    Sorry, 112 2nd paragraph. Now, nuff said. MiyaMiyaMiya wa? Ex Parte Miyazaki, that's what.

    "Ah, sounds like you're of the opinion that the patent drafter missed the boat, rather than made a deliberate decision to be artfully inconsistent. Guess we'll never know. "

    Actually, from what I can tell, the patent drafter himself did not miss the boat.

    See here:

    "The court also rejected the idea that "power" and "voltage" were used interchangeably in the spec."

    That's because the drafter, who was likely not a mor on, did not use the two terms interchaneably.

    For instance:

    "As support for this argument, the patentee pointed to various passages that described the power supply circuit solely in terms of volts (e.g., "5 volt power supply circuit")."

    That snippet from the spec is not improper/informal at all, a "5 volt power supply circuit" is fine to describe what a circuit is and it certainly isn't trying to redefine what power is to include voltage. What the phrase means is that the circuit provides 5 volts, regardless of what load you have attached (within reasonable limits of course) at a variable undefined current (dependent upon the load resistance/impedence) to provide power. It is most certainly not describing power in terms of volts or describing power to be volts or any such nonsense.

    The court shouldn't even need:

    "But the court found that other portions of the spec clarified this usage by describing the circuit in terms of a combination of power and voltage (e.g. "steady 5 volt DC [direct current] power")."

    ^that because it is extraneous. But it does seal the coffin that the claim construction was already buried in with a few thousand nails.

    Thus, it was the litigators/patentee trying to make an issue out of this missed the boat because they are re tards. Likely what you should have said here:

    "According to the patentee, a POSITA would understand that the inventors intended for "power" to mean "voltage" because the specification did not explicitly adopt the ordinary meaning,"

    was:

    "According to the patentee's LITIGATION attorney, a POSITA would understand that the inventors intended for "power" to mean "voltage" because the specification did not explicitly adopt the ordinary meaning"

    Power always means the same thing. Even the wiki gets it right:

    http://en.wikipedia.org/wiki/Power_(physics)#Instantaneous_electrical_power

    The definition, or meaning, of "power" has zip to do with I times V, even in the electrical arts. However, at the same time, it just so happens that I times V is one way of determining the power. Both of the attorneys in this case argued in a lame fashion. The attorney arguing against the "voltage" reading should have merely cited what "power" actually means in this context, in all arts, at all times, rather than giving the lame V times I.

    Power when being used in the context of energy of some kind is always "the rate at which work is performed or energy is converted" or something meaning the same thing as that. "Voltage" aka "potential energy" doesn't even come close to that, in any context, informal or otherwise.

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  6. >"According to the patentee's LITIGATION
    >attorney, a POSITA would understand that the
    >inventors intended for "power" to mean
    >"voltage"

    OK. I agree that another view of this case is what the ligitator did rather than what the prosecutor did. [In fact, yours is probably the most natural reading of the case.] That is, given a claim that didn't read on the accused with a straightforward claim construction, what arguments can we make for a claim construction that does read on the accused.

    I suspect that many litigators have to advocate best they can given bad facts -- make lemonade out of lemons, as it were.

    >Both of the attorneys in this case argued in a
    >lame fashion. The attorney arguing against the
    >"voltage" reading should have merely cited >what "power" actually means in this context,
    >in all arts, at all times, rather than giving
    >the lame V times I.

    Gotcha. I wonder about the background of the attorneys on the claim construction team -- both sides. PTO number? PTO number but never prosecuted? EE? EE who has been practicing law (not engineering) for 20 years?

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  7. "using a boost circuit to increase the power of the secondary cell "

    Boost circuits increase voltage, and power is actually lost. I don't know of any boost circuits that are 100% efficient. It looks like the inconsistent use of "power" for "votage" here results in a patent claim that can't be enforced, unless "power" is taken to mean "voltage." I can't think why this case would indicate that there is some advantage for the patentee in using the wrong word here.

    TINLA IANYL

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  8. >Boost circuits increase voltage, and
    >power is actually lost.

    Sounds like you folks know way more about the technology than I do -- I'm a CS major, not EE.

    >results in a patent claim that can't be
    >enforced, unless "power" is taken to mean
    >"voltage."

    Exactly. I hinted as much in my original post, when I said that infringer wouldn't have had a case without this creative claim construction.

    >I can't think why this case would indicate
    >that there is some advantage for the
    >patentee in using the wrong word here.

    I agree that using the *wrong* word is to be avoided.

    As I said, I'm not a EE so I wasn't sure from reading the case whether this was a litigation attorney making the best of a bad situation (wrong word used in the claims) or a prosecuting attorney getting creative and giving the litigators some room (alternative word used in the claim).

    I wanted to read this case as the latter, but it sounds like it might have been the former.

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  9. >prosecuting attorney getting creative and
    >giving the litigators some room
    >(alternative word used in the claim).

    FWIW, I do think see value in using alternative terms. Precisely because you might get different claim constructions that allow you to catch an infringer with one claim that might escape another.

    I'm thinking of something along the lines of determining vs. evaluating vs. selecting. Not the strongest example, but in the ball park.

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