ORDER

D.P. MARSHALL, JR., District Judge.

1. Summary. The parties compete in making and selling high-end riding mowers. Robert Foster, an inventor, has connections on both sides of the case. He used to work with Bad Boy, left, and now works with Spartan-related companies.* As part of the leaving, Foster allegedly assigned United States Patent No. 7,708,292—an "Independent Four Wheel Vibration Damping System for Riding Mowers"—to Bad Boy. The parties' disputes have carried them into state and federal courts. Bad Boy here alleges that the Spartan SRT line of mowers infringes the '292 patent. Spartan denies infringement.

The Court must construe some disputed terms in the '292 patent. What did its five claims mean to a skilled artisan when the patent issued? 35 U.S.C. § 112(a); Phillips v. AWH Corp., 415 F.3d 1303, 1311-14 (Fed. Cir. 2005). The parties have filed comprehensive briefs. The Court heard helpful argument at a hearing, Markman v. Westview Instruments, Inc., 517 U.S. 370 (1996), and afterward got an informative tutorial about the vibration-damping technology in Bad Boy's mower. No expert testimony or other extrinsic evidence was considered.* The patent's meaning is in the claims' words, informed by the whole patent, including the specification. Phillips, 415 F.3d at 1313-14. The prosecution history, which is also intrinsic evidence of meaning, is helpful on one point, too. Phillips, 415 F.3d at 1317.

2. Claims. Here are Bad Boy's '292 claims, with the disputed terms in bold.

The invention claimed is:

United States Patent No. 7,708,292.

To summarize, Bad Boy made five claims, two independent and three dependent. Claim 1 is independent and sets out the basic scheme: a riding mower with a vibration-damping system. Claims 2, 3, and 4 are dependent limitations that explain how this system works: Claim 2 defines the forward wheel assemblies; Claim 3 clarifies the need for elastomeric pillows next to the wheels; and Claim 4 propounds a pivoting suspension cage on the rear wheels. Claim 5 synthesizes all these details into a single, independent claim: a riding mower with mechanisms that provide smooth suspension.

3. Scope. Spartan's first point is that Bad Boy disavowed all vibration-damping systems except the one shown in the preferred embodiment. Spartan cites phrases scattered throughout the patent in support of this contention, arguing that Bad Boy disavowed other embodiments both explicitly and implicitly. The Court is not persuaded. The law presumes against disavowal. Renishaw PLC v. Marposs Societa' per Azioni, 158 F.3d 1243, 1250 (Fed. Cir. 1998). Spartan is correct that this presumption can be overcome when it is made clear—explicitly or implicitly—that the patent is limited to the preferred embodiment. Trustees of Columbia Univ. in City of New York v. Symantec Corp., 811 F.3d 1359, 1364 (Fed. Cir. 2016). But this standard is exacting. Poly-America, L.P. v. API Industries, Inc., 839 F.3d 1131, 1136 (Fed. Cir. 2016). And there's no clear evidence in the '292 patent that satisfies this exacting standard.

Spartan argues from the specification's words, pointing (for example) to references to the "present invention." It also argues substantive points about specification, effectiveness, and disparagement. The thrust of all these arguments is that Bad Boy's patent is so specific that no embodiment other than the preferred one is protected. Spartan's point has superficial power. Like almost every writing, this patent could have benefited from a better choice of words. That fact doesn't change the legal analysis, though. The Court isn't supposed to consider just the words' surface; it's supposed to discern what the patent means as whole, taking all the words in context. One of Spartan's main precedents underlines the point. "[T]he construction that stays true to the claim language and most naturally aligns with the patent's description of the invention will be, in the end, the correct construction." Trustees of Columbia Univ., 811 F.3d at 1366.

Taken in context, Bad Boy's five claims refer not just and only to the preferred embodiment, but to a novel concept: using elastomeric pillows in a certain way for independent vibration-damping on a lawnmower. The specifics Spartan highlights are meant to describe how this concept works, not to limit it. Phillips, 415 F.3d at 1323. In other words, it's all about the key ingredient and not the dish. There are many ways to use these damping pillows in mower suspension; and many skilled artisans could tinker with the version laid out in the preferred embodiment. That tinkering might result in some improvements or slightly different mowers, but the key ingredient would remain the same in each. The specifics cited by Spartan do some limiting, but the general intention of the patent is otherwise clear to a skilled artisan. The '292 patent protects the novel use of certain pillows in mower suspension.

Spartan is correct, however, that Bad Boy disclaimed systems using springs, shock absorbers, and airbags. This is where the specifics have teeth. Bad Boy's patent description talks up the benefits of using elastomeric pillows-while disparaging other available methods. How Bad Boy convinced the United States Patent and Trademark Office that its suspension system differed from the Melone patent provides a clear example. Pillows, Bad Boy said, work to prevent the jamming that had undermined previous shock-absorbing technologies on mowers. This pitch was and is convincing. But it also limits Bad Boy's claims to certain squishy pillows — cushions that rely on their own material, not what's inside them (like an airbag), for damping—because that's what makes the '292 suspension system unique and immune from jamming. Other methods of shock absorption aren't protected.

Spartan's last global point, indefiniteness, doesn't meet the standard required by law. A claim is indefinite if it "fail[s] to inform, with reasonable certainty, those skilled in the art about the scope of the invention." Nautilus, Inc. v. Biosig Instruments, Inc., 134 S.Ct. 2120, 2124 (2014). That sort of uncertainty can be fatal because the goal of claim construction is to "define the invention to which [Bad Boy] is entitled the right to exclude." Phillips, 415 F.3d at 1312. The problem for Spartan, however, is that the disputed terms do give a skilled artisan notice about what the '292 patent protects: vibration-absorbing elastomeric pillows between the wheels and the frame of a riding mower. To absorb that vibration, the pillows must be fastened between the two. Any skilled mechanic (not to mention many unskilled enthusiasts) can see the import of this. And that import is focused on the pillows and their function, not the bolts or the frame. What matters — both in the engineering and in the law — is that the pillows need to be fastened in order to dampen vibration, not the precise way in which they are fastened. Indefiniteness isn't an issue for this patent.

4. Terms. There are eleven terms before the Court, three of which are agreed and eight of which are disputed. They touch all five claims. And they also affect the patent's scope. The Court construes these terms to keep faith with the '292 patent and help the jury decide about Spartan's alleged infringement.

Agreed Terms. The parties agree on how to construe three terms. The Court is a bit skeptical about whether any construction is needed. A jury would understand the plain meaning here. But there is little harm in clarification, particularly when it eliminates confusing legal jargon, such as the superfluous use of the word "said." The Court therefore adopts the parties' agreed constructions.

Disputed Terms. The parties have organized them into three groups: the elastomeric pillow terms, the term "either," and the suspension cage terms. This architecture is helpful.

Elastomeric Pillow Terms

Bad Boy disclaimed other vibration-damping systems during the application process, in its specification, and by disparaging prior art. But the general subject matter was not disavowed and the '292 patent's terms are clear, not indefinite. This patent protects vibration-damping systems that use elastomeric pillows as cushions between a lawnmower's wheels and frame. The pillows must be attached to both in order to function. And, to avoid jamming, each pillow must be able to prevent debris infiltration, plus absorb shock even if what's inside the pillow (if anything other than the primary elastomer is used to make the pillow) happens to fail. In other words, the pillow terms are all about the resilient material that makes up the pillow.

Either

The next group involves only one term. That term depends on the appearance of the word either in the phrase "said pillow is disposed on either side of each said wheel." Does either mean both sides of the wheel or simply one side, without preference? Both parties make compelling arguments. Bad Boy points to the plain meaning of the word, while Spartan points to the specification. That specification, read alongside the claims, implies that there is something unique about having a pair of pillows. '292 Patent, Col. III. 13-17. But that implication isn't enough to overcome the plain meaning of the claims. Claim 3, for example, refers to "said pillow" in the singular. And the word "either" has a double meaning, both colloquially and to skilled artisans. A passerby and an engineer might say "there are utility lines on either side of this road" and "the utility lines could be run on either side of this road." It's reasonable that a pillow located on one side—or two pillows, one on each side — could provide the benefit described in the patent. The Court declines to limit the term.

Suspension Cage Terms

Here again, the Court is asked to construe terms that aren't obviously murky. Spartan is right, however, that there is some latent ambiguity. What is a suspension cage? The term isn't indefinite — the description makes clear what's going on. Clarity comes by reading the claims against the specification's background. That supplementation, in turn, limits the claims to structures that pivot relative to the frame and support the wheel assemblies.

Informed by the parties' helpful arguments, and considering only intrinsic evidence, the Court concludes that the best construction of the disputed terms is mostly no construction. Bad Boy's disclaimer of airbags, and some needed particulars provided only in the specification, require some limitation of the five claims. Otherwise, the parties' disputes are really about infringement, which is for the jury in due course. The Court approves the parties' agreed constructions, modifies Bad Boy's proposed definition of "elastomeric pillow," adopts Spartan's proposed definition of "each said wheel," and adopts Bad Boy's proposed definition of "suspension cage." All other terms proceed without construction.

So Ordered.