The Deere v. Gramm Analysis

by Dennis Crouch

Deere & Co. v. Gramm (Fed. Cir. 2021).

In 1966, the US Supreme Court decided Graham v. John Deere, and established the framework for adjudging obviousness under the 1952 Patent Act. In the processes Graham’s plow patent was deemed obvious.  In this new case, Deere is looking to invalidate Richard Gramm’s patent. This time though the patentee prevails.

Gramm’s  US Patent No. 6,202,395 covers a sensor and controller for the head-height of a combine harvester.  The case is interesting because of its similarity to the spring-loaded shear in the 1966 case. Here, “a flexible sensor arm that engages the soil and is
dragged across the ground” as the giant tractor rolls along.

The particular novel aspects of the invention here appear to be related to what happens when the Combine is placed in reverse — we don’t want to bob to snap off.  The solution is a spring (“biasing means”) for keeping the arm at an incline but allows for displacement when you reverse.  The spring then uses Hooke’s Law to encourage the sensor arm to return to its original position.

Deere petitioned the USPTO for inter partes review (IPR). Although the Board granted the petition, it eventually sided with the patentee and found that none of the challenged claims had been proven obvious. The case has included some partial institution mix-up following SAS, and the CAFC has previously affirmed the holding with regard to some of the claims, this appeal is related to claims 12-26.

Claimed Biasing Means: That spring discussed above – the claims require a “biasing means for urging said arm to a selected inclined orientation relative to
vertical …”  The parties agree that the claim term is properly interpreted as means-plus-function because “biasing” is a functional limitation rather than structural. Further, the patent document discloses a “coiled spring” that performs the claimed function. Thus – as required by the text of 112p6, the claim limitation is interpreted as requiring a coiled spring “and equivalents thereof” that performs the same function.

In the IPR, this limited view of “biasing means” was helpful to the patentee because it narrowed the scope of prior art that read upon the invention.  On appeal, the Federal Circuit confirmed that the prior art reference (US3611286) did not disclose the biasing means. An image from the prior-art patent is below.  To be clear, the reference does disclose a coiled spring, but it did not operate in the same way — to urge the arm to move toward an “inclined orientation.”


The true key controversy of the appeal was really about whether this issue should be reviewed de novo as a claim construction dispute or instead with substantial deference as a factual finding regarding the scope of the prior art.  As usual, the appellant wanted de novo review, but the Federal Circuit refused:

First and foremost, we reject Deere’s attempt to obtain de novo review of a factual finding by reframing it as though it presents a claim construction issue. . . . .

Here, after construing the biasing means limitation, the Board determined that [the prior art] did not teach the first function of the biasing means. That is a factual finding subject to appellate review for substantial evidence. . . . Deere attempts to contort the Board’s opinion by suggesting that the Board actually misconstrued the claim in such a way so as to not read on the teachings of Cleveland. We are not persuaded by that argument, which seeks to blur the clear delineation in the law between the two steps of the invalidity analysis.

Slip Op. Notably, the court does not actually do a very good job of explaining why this particular dispute is not a claim construction dispute except that the PTAB did not see it as claim construction either.

Judgment Affirmed in Favor of Patentee

19 thoughts on “The Deere v. Gramm Analysis

  1. 4

    There are two springs in the mechanism of the ‘395 patent – spring 98, which, as you point out, is part of the flexible “finger” (sensor arm 96); and coiled spring 114 that is part of the bracket assembly to which the sensor arm is attached.
    The coiled spring 114 “urges sensor arm 96 in a counterclockwise direction of rotation about the motion sensor 48” and “maintains the sensor arm 96 at an inclined angle.”

    Per the CAFC’s opinion, coiled spring 114 is the biasing means, not spring 98.

    In the prior art Cleveland reference, spring 38 is part of the “arm” and makes it flexible. Your reaction that “But incorporating a coil spring into the finger length doesn’t equip that finger with any “biasing means” does it?” is consistent with the holding that the Cleveland reference did not have a biasing means. Cleveland didn’t have a separate spring like coiled spring 114, so it didn’t have a biasing means.

    1. 4.1

      OK, Pilgrim. Column 6, line 43, for example. Overlooked that. Thanks.

      Now I’m looking to see where the patent designates that little breakback spring a “biasing means”.

      Remarkable, Iwould say, how such a little thing like a bog standard breakback spring can confer patentability on an old sensor finger. Mind you, one would think though that Deere would have the resources and imagination to find a non-infringing design around.

      1. 4.1.1

        Mulling over the “design around” issue, I am wondering what is “equivalent” to the illustrated “biasing means” namely the spring 114. Just about anything, I should think, that is effective to protect the finger from buckling when the combine header moves rearwardly. In practice then, the scope of protection is seriously wide, despite the choice of M + F claim language.


          Max, “equivalency” for a means-function claim is limited to equivalents of the means disclosed in the specification.


            Indeed. Just so, Paul. But for those giving, say, an FTO opinion to a client, who can really say whether any particular design of “biasing means” contemplated by that client is or is not “equivalent” to the spring 114? If nobody can say, then 112(6) hardly constrains the scope of the claim at all. Conversely, if “equivalent” means “same” then designing around is no problem at all.

            Which is it? Can you say, for any given patent.

            I have another question: thinking still about spring 114, about 2 cents to make, is the reasonable royalty damages award going to be set by the price of the combine harvester itself (USD 100, 000 or so)?


              Max, it should not be difficult to get a non-infringement opinion in this means-function claiming situation for a distance sensor that does not use any spring to restore the desired angle of the sensor after machine reversal. But having been sued, it is difficult to get many judges to make prompt Markman claim interpretations and provide non-infringement summary judgements before defendants have had to spend a fortune on sweeping document discovery, depositions, trial preparations, etc. Hence, frequent suit settlements for less than that, or IPRs, or 101 motions.
              Yes, infringement damage recovery here would probably involve damages “apportionment” probably based on the whole sensor, not just one spring. I think you would find that $100K is considerably less than what most new crop harvesting machines cost.


                OK, thanks Paul. A prohibition on the use of anything in the nature of a “spring” strikes me as a very handsome scope of protection though.

                Yes, I daresay you are entirely right, that 100k is indeed lamentably inadequate for the purchase of a modern combine harvester. Still I have no problem with basing damages on the cost of the sensor assembly.

                As you point out, it doesn’t matter how many non-infringement opinions you have in hand, none of them can stop a patent owner commencing infringement proceedings.

                1. RE: “ doesn’t matter how many non-infringement opinions you have in hand, none of them can stop a patent owner commencing infringement proceedings.”
                  Max, is that also true in your view for European patent infringement suits? That is, a low likelihood of early low cost summary judgement for invalidity or even for clear non-infringement? Don’t you have at least high assigned costs for suing and losing [not just sanctions for some baseless suits or litigation misconduct]?

                2. Paul, Europe follows a “loser pays” rule. That’s a serious deterrent to frivolous suits. Further, it has no punitive damages, no triple damages. People litigate to get an injunction. Absent a convincing case, they’re not going to get one, and Defendants know it. Attacks on validity succeed on attaining a “more likely than not” threshold.

                  Litigating more in hope than expectation is barely known. There is no equity, no discovery, no x-exam (except in The British Isles) no fishing expeditions.

                  All in all, plenty of people threaten infringement proceedings but seldom does a case get to trial.

                3. Here, wear my eyeglasses – they work fine for me and thus should cure your eyesight problems.


  2. 3

    I have to say that I’m shocked by this case. I have looked at Dennis’s write up, the ‘395 patent and the ‘286 prior art and find myself totally confused about the biasing means. In this particular patent, what exactly is a “biasing means”?

    I mean, it is recited in the claim but I have failed to find in the specification any mention at all of any “biasing means”. Further, I don’t see why the spring on which everybody is focussing does any biasing of the finger at all and certainly not into its pre-set, default, relaxed rearwardly inclined disposition.

    For me, what the drawing shows and the claims claim is a height sensor finger device that is inclined rearwardly, and in which a rotation sensor 48 reports to the header controller any increase in the rearward angle of inclination (which corresponds to a diminution of the header height above the ground over which the combine is advancing.

    Because combines sometimes have to move (for example on encountering an obstruction such as a dead animal) briefly in a reverse direction, one needs to protect the finger from being broken by that reverse movement. Duh!

    One way to do this is to impart to the finger length enough flexibility to bend backwards, enough to accommodate the reverse movement.

    One way to render the finger flexible enough is to make it out of a coil spring. But incorporating a coil spring into the finger length doesn’t equip that finger with any “biasing means” does it? I mean, suppose in my kitchen there is a wooden spoon and a spoon of plastic. Does the plastic one have a biasing means and the wooden one not? Come on, folks, think about it.

    Other than that, and being European, I’m wondering what was the realistic prior art starting point. How can it be that the plowing aid of ‘286 is the closest thing to the combine harvester of the patent?

    In its Background section, the patent tells us that “There are various approaches to maintaining the header a predetermined height above the soil”. I would be amazed if they did not include the ubiquitous “trailing finger” method of monitoring working height. Can it be, that the courts are here recognising patentability in the step of making that finger flexible? Seriously?

    Should I now read the Decision? Or would that be a waste of my time?

  3. 2

    Note that this old patent’s application was written back when “means-plus-function” claims [expressly using the word “means” as here to thus trigger that presumption] were far more common than they are now. But this may be a good example of why having at least one such claim in addition to the others can be a good idea for surviving an IPR by distinguishing prior art with a 112 last paragraph claim reading. [I did wonder why the commonly-used car “curb feelers” of my ancient youth were not cited?]
    BTW, in case you were wondering, replacing a tough mechanical distance sensor like this with a modern electronic distance sensor [such as cars now use] is not as easy in the extremely dusty, muddy and uneven environment of farm harvesting machines.

    1. 2.1

      “BTW, in case you were wondering, replacing a tough mechanical distance sensor like this with a modern electronic distance sensor [such as cars now use] is not as easy in the extremely dusty, muddy and uneven environment of farm harvesting machines.”

      Simple substitution. Obvious.


          Yes they are. But if you think you’re going to argue to an examiner that “replacing a mechanical sensor with an electronic sensor is not as easy as…” and get anything more than a form paragraph, or two, in response then you’re kidding yourself.


            Yes, if you are talking about patent application examinations [as opposed to jury arguments] you probably should, get an obviousness rejection for mere substitution if you did not have any claim features and spec or declaration distinctions to point to as to why the substitution of known equivalents for distance measuring was unobvious for the claimed purpose or application.

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