Baseball is often called a "game of inches," whether one is describing the strike zone, a close play at the plate, or a liner past third base that just kicks up the chalk to stay fair. Indeed, hitting is truly about inches. Pitchers try to locate their pitches on the edges of the plate or have them run just out of the strike zone to prevent the batter from making contact with the "sweet spot" of the bat – a ball struck just off the main part of barrel might result in a soft fly to shortstop, while the same swing where the ball contacts the sweet spot of the bat might result in a smash to the outfield gap. In wooden bats, the sweet spot is generally located in the area above the manufacturer's label, about 5-7 inches from the end of the barrel (essentially, the node on the bat that results in minimal vibration when striking a ball). Employing the physics principle of Coefficient of Restitution (COR), the more a baseball bat vibrates upon impact with the ball, the more energy the bat retains, resulting in less energy returned to the ball after collision (and a stinging feeling in the batter's hands); conversely, the less a bat vibrates, the more kinetic energy is transferred to the ball, resulting in the ball travelling a greater distance.
Metal bats are hollow and work a little bit differently, as they are lighter (resulting in a faster swing) and bend slightly upon impact with the ball (i.e., the trampoline effect), causing the ball to travel farther and faster from the crack (or ping) of the bat. As a result, baseball and softball associations have established metal bat performance standards based upon the bat's particular COR at the barrel, setting a maximum COR that minimizes the trampoline effect and the speed of the ball off the bat. The engineering trick is how to modify a metal bat's design to fit within the guidelines, but without making the bat too heavy or overly reducing its performance outside of the sweet spot zone. It is this innovation that was the subject of a patent infringement suit between two sporting goods companies, Easton Baseball/Softball Inc. ("Easton") and Wilson Sporting Goods ("Wilson"). (Easton Baseball/Softball Inc. v. Wilson Sporting Goods Co., No. 15-9221 (C.D. Cal. filed Nov. 30, 2015)).
Going to bat for its own IP, Easton sued Wilson for allegedly infringing its patents (Nos. 8,480,519 and 8,795,108) on a baseball bat with "governed performance" – essentially, a bat design that included stiffening and dampening elements positioned between the sweet spot and the handle to "selectively reduce the barrel's performance without appreciably increasing the bat's moment of inertia." Easton claimed that Wilson produced bats that unlawfully used Easton's patented stiffening element. In its defense, Wilson argued that there was ambiguity with how the patents defined the term "sweet spot" and that the stiffeners in its allegedly infringing bats were not located in the positions claimed in the patents-at-issue. In a battle of experts, the parties engaged in a pitching duel over whether the term "sweet spot" referred to a location based upon points of vibration within the bat or merely as the spot of "maximum performance location" and whether the experts were qualified or even conducted sufficient testing to determine if infringement occurred.
Notably, in its motion for partial summary judgment, Wilson also argued that one of Easton's patents was invalid due to the presence of prior art – in fact, Wilson claimed that its own Ultimate Fastpitch Bat (UFB), released about seven years prior to the priority date of one of Wilson's patents, used stiffening elements made of cork between the sweet spot and the handle that anticipated all of the claims of Easton's patented design.
And here's the pitch… Unfortunately, we will never discover if the court would have found infringement or else batted away Easton's claims. With the trial date looming, the parties settled the matter and stipulated to the dismissal of the action (perhaps, Easton did not want to risk an order of invalidity of one of its patents, while Wilson wished to avoid a potential large damage award). Thus, in this bat design litigation of inches, the parties deemed it better to take a pitch rather than swing away.